Difference between revisions of "Protocol"

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(Retire the term "global palette"; explain registries more generally.)
(added resource location to entity movement packets)
 
(201 intermediate revisions by 36 users not shown)
Line 5: Line 5:
 
   |ICON =
 
   |ICON =
 
   |HEADING = Heads up!
 
   |HEADING = Heads up!
   |CONTENT = This article is about the protocol for the latest '''stable''' release of Minecraft '''Java Edition''' ([[Protocol version numbers|1.20.2, protocol 764]]). For the Java Edition pre-releases, see [[Pre-release protocol]]. For the incomplete Bedrock Edition docs, see [[Bedrock Protocol]]. For the old Pocket Edition, see [[Pocket Edition Protocol Documentation]].
+
   |CONTENT = This article is about the protocol for a '''stable''' release of Minecraft '''Java Edition''' ([[Protocol version numbers|1.21.1, protocol 767]]). For the Java Edition pre-releases, see [[Pre-release protocol]]. For the incomplete Bedrock Edition docs, see [[Bedrock Protocol]]. For the old Pocket Edition, see [[Pocket Edition Protocol Documentation]].
 
}}
 
}}
  
Line 54: Line 54:
 
  |-
 
  |-
 
  | Block state
 
  | Block state
  | Each block in Minecraft has a 0 or more properties, which in turn may have any number of possible values. These represent, for example, the orientations of blocks, poweredness states of redstone components, and so on. Each of the possible permutations of property values for a block is a distinct block state. The block state registry assigns a numeric identifier to every block state of every block.
+
  | Each block in Minecraft has 0 or more properties, which in turn may have any number of possible values. These represent, for example, the orientations of blocks, poweredness states of redstone components, and so on. Each of the possible permutations of property values for a block is a distinct block state. The block state registry assigns a numeric identifier to every block state of every block.
  
A current list of properties and state ID ranges is found on [https://pokechu22.github.io/Burger/1.20.1.html burger].
+
A current list of properties and state ID ranges is found on [https://pokechu22.github.io/Burger/1.21.html burger].
  
Alternatively, the vanilla server now includes an option to export the current block state ID mapping, by running <code>java -cp minecraft_server.jar net.minecraft.data.Main --reports</code>.  See [[Data Generators]] for more information.
+
Alternatively, the vanilla server now includes an option to export the current block state ID mapping, by running <code>java -DbundlerMainClass=net.minecraft.data.Main -jar minecraft_server.jar --reports</code>.  See [[Data Generators]] for more information.
 
  |-
 
  |-
 
  | Notchian
 
  | Notchian
Line 69: Line 69:
 
== Packet format ==
 
== Packet format ==
  
Packets cannot be larger than 2<sup>21</sup> &minus; 1 or 2097151 bytes (the maximum that can be sent in a 3-byte VarInt).  For compressed packets, this applies to both the compressed length and uncompressed lengths.
+
Packets cannot be larger than 2<sup>21</sup> &minus; 1 or 2097151 bytes (the maximum that can be sent in a 3-byte {{Type|VarInt}}). Moreover, the length field must not be longer than 3 bytes, even if the encoded value is within the limit. Unnecessarily long encodings at 3 bytes or below are still allowed.  For compressed packets, this applies to the Packet Length field, i.e. the compressed length.
  
 
=== Without compression ===
 
=== Without compression ===
Line 79: Line 79:
 
  |-
 
  |-
 
  | Length
 
  | Length
  | VarInt
+
  | {{Type|VarInt}}
 
  | Length of Packet ID + Data
 
  | Length of Packet ID + Data
 
  |-
 
  |-
 
  | Packet ID
 
  | Packet ID
  | VarInt
+
  | {{Type|VarInt}}
  |
+
  | Corresponds to <code>protocol_id</code> from [[Data Generators#Packets report|the server's packet report]]
 
  |-
 
  |-
 
  | Data
 
  | Data
  | Byte Array
+
  | {{Type|Byte Array}}
 
  | Depends on the connection state and packet ID, see the sections below
 
  | Depends on the connection state and packet ID, see the sections below
 
  |}
 
  |}
Line 96: Line 96:
  
 
{| class=wikitable
 
{| class=wikitable
 +
! Present?
 
  ! Compressed?
 
  ! Compressed?
 
  ! Field Name
 
  ! Field Name
Line 101: Line 102:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
 +
| always
 
  | No
 
  | No
 
  | Packet Length
 
  | Packet Length
  | VarInt
+
  | {{Type|VarInt}}
  | Length of (Data Length) + Compressed length of (Packet ID + Data)
+
  | Length of (Data Length) + length of compressed (Packet ID + Data)
 
  |-
 
  |-
 +
| rowspan="3"| if size >= threshold
 
  | No
 
  | No
 
  | Data Length
 
  | Data Length
  | VarInt
+
  | {{Type|VarInt}}
  | Length of uncompressed (Packet ID + Data) or 0
+
  | Length of uncompressed (Packet ID + Data)
 
  |-
 
  |-
 
  | rowspan="2"| Yes
 
  | rowspan="2"| Yes
 
  | Packet ID
 
  | Packet ID
  | VarInt
+
  | {{Type|VarInt}}
 
  | zlib compressed packet ID (see the sections below)
 
  | zlib compressed packet ID (see the sections below)
 
  |-
 
  |-
 
  | Data
 
  | Data
  | Byte Array
+
  | {{Type|Byte Array}}
 
  | zlib compressed packet data (see the sections below)
 
  | zlib compressed packet data (see the sections below)
 +
|-
 +
| rowspan="3"| if size < threshold
 +
| rowspan="3"| No
 +
| Data Length
 +
| {{Type|VarInt}}
 +
| 0 to indicate uncompressed
 +
|-
 +
| Packet ID
 +
| {{Type|VarInt}}
 +
| packet ID (see the sections below)
 +
|-
 +
| Data
 +
| {{Type|Byte Array}}
 +
| packet data (see the sections below)
 
  |}
 
  |}
  
If the size of the buffer containing the packet data and ID (as a VarInt) is smaller than the threshold specified in the packet [[#Set Compression|Set Compression]]. It will be sent as uncompressed. This is done by setting the data length as 0. (Comparable to sending a non-compressed format with an extra 0 between the length, and packet data).
+
For serverbound packets, the uncompressed length of (Packet ID + Data) must not be greater than 2<sup>23</sup> or 8388608 bytes. Not that a length equal to 2<sup>23</sup> is permitted, which differs from the compressed length limit. The Notchian client, on the other hand, has no limit for the uncompressed length of incoming compressed packets.
  
If it's larger than the threshold, then it follows the regular compressed protocol format.
+
If the size of the buffer containing the packet data and ID (as a {{Type|VarInt}}) is smaller than the threshold specified in the packet [[#Set Compression|Set Compression]]. It will be sent as uncompressed. This is done by setting the data length as 0. (Comparable to sending a non-compressed format with an extra 0 between the length, and packet data).
 +
 
 +
If it's larger than or equal to the threshold, then it follows the regular compressed protocol format.
 +
 
 +
The Notchian server (but not client) rejects compressed packets smaller than the threshold. Uncompressed packets exceeding the threshold, however, are accepted.
  
 
Compression can be disabled by sending the packet [[#Set Compression|Set Compression]] with a negative Threshold, or not sending the Set Compression packet at all.
 
Compression can be disabled by sending the packet [[#Set Compression|Set Compression]] with a negative Threshold, or not sending the Set Compression packet at all.
Line 147: Line 168:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="4"| 0x00
+
  | rowspan="4"| ''protocol:''<br/><code>0x00</code><br/><br/>''resource:''<br/><code>intention</code>
 
  | rowspan="4"| Handshaking
 
  | rowspan="4"| Handshaking
 
  | rowspan="4"| Server
 
  | rowspan="4"| Server
 
  | Protocol Version
 
  | Protocol Version
  | VarInt
+
  | {{Type|VarInt}}
  | See [[protocol version numbers]] (currently 764 in Minecraft 1.20.2).
+
  | See [[protocol version numbers]] (currently 767 in Minecraft 1.21).
 
  |-
 
  |-
 
  | Server Address
 
  | Server Address
  | String (255)
+
  | {{Type|String}} (255)
 
  | Hostname or IP, e.g. localhost or 127.0.0.1, that was used to connect. The Notchian server does not use this information. Note that SRV records are a simple redirect, e.g. if _minecraft._tcp.example.com points to mc.example.org, users connecting to example.com will provide example.org as server address in addition to connecting to it.
 
  | Hostname or IP, e.g. localhost or 127.0.0.1, that was used to connect. The Notchian server does not use this information. Note that SRV records are a simple redirect, e.g. if _minecraft._tcp.example.com points to mc.example.org, users connecting to example.com will provide example.org as server address in addition to connecting to it.
 
  |-
 
  |-
 
  | Server Port
 
  | Server Port
  | Unsigned Short
+
  | {{Type|Unsigned Short}}
 
  | Default is 25565. The Notchian server does not use this information.
 
  | Default is 25565. The Notchian server does not use this information.
 
  |-
 
  |-
 
  | Next State
 
  | Next State
  | VarInt Enum
+
  | {{Type|VarInt}} {{Type|Enum}}
  | 1 for [[#Status|Status]], 2 for [[#Login|Login]].
+
  | 1 for [[#Status|Status]], 2 for [[#Login|Login]], 3 for [[#Login|Transfer]].
 
  |}
 
  |}
  
 
==== Legacy Server List Ping ====
 
==== Legacy Server List Ping ====
  
{{Warning|This packet uses a nonstandard format. It is never length-prefixed, and the packet ID is an Unsigned Byte instead of a VarInt.}}
+
{{Warning|This packet uses a nonstandard format. It is never length-prefixed, and the packet ID is an {{Type|Unsigned Byte}} instead of a {{Type|VarInt}}.}}
  
 
While not technically part of the current protocol, legacy clients may send this packet to initiate [[Server List Ping]], and modern servers should handle it correctly.
 
While not technically part of the current protocol, legacy clients may send this packet to initiate [[Server List Ping]], and modern servers should handle it correctly.
Line 186: Line 207:
 
  | Server
 
  | Server
 
  | Payload
 
  | Payload
  | Unsigned Byte
+
  | {{Type|Unsigned Byte}}
 
  | always 1 (<code>0x01</code>).
 
  | always 1 (<code>0x01</code>).
 
  |}
 
  |}
Line 207: Line 228:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="2"| 0x00
+
  | ''protocol:''<br/><code>0x00</code><br/><br/>''resource:''<br/><code>status_response</code>
  | rowspan="2"| Status
+
  | Status
  | rowspan="2"| Client
+
  | Client
|-
 
 
  | JSON Response
 
  | JSON Response
  | String (32767)
+
  | {{Type|String}} (32767)
  | See [[Server List Ping#Status Response]]; as with all strings this is prefixed by its length as a VarInt.
+
  | See [[Server List Ping#Status Response]]; as with all strings this is prefixed by its length as a {{Type|VarInt}}.
 
  |}
 
  |}
  
==== Ping Response (status) ====
+
==== Pong Response (status) ====
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 226: Line 246:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | 0x01
+
  | ''protocol:''<br/><code>0x01</code><br/><br/>''resource:''<br/><code>pong_response</code>
 
  | Status
 
  | Status
 
  | Client
 
  | Client
 
  | Payload
 
  | Payload
  | Long
+
  | {{Type|Long}}
 
  | Should be the same as sent by the client.
 
  | Should be the same as sent by the client.
 
  |}
 
  |}
Line 248: Line 268:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | 0x00
+
  | ''protocol:''<br/><code>0x00</code><br/><br/>''resource:''<br/><code>status_request</code>
 
  | Status
 
  | Status
 
  | Server
 
  | Server
Line 264: Line 284:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | 0x01
+
  | ''protocol:''<br/><code>0x01</code><br/><br/>''resource:''<br/><code>ping_request</code>
 
  | Status
 
  | Status
 
  | Server
 
  | Server
 
  | Payload
 
  | Payload
  | Long
+
  | {{Type|Long}}
 
  | May be any number. Notchian clients use a system-dependent time value which is counted in milliseconds.
 
  | May be any number. Notchian clients use a system-dependent time value which is counted in milliseconds.
 
  |}
 
  |}
Line 279: Line 299:
 
# C→S: [[#Login Start|Login Start]]
 
# C→S: [[#Login Start|Login Start]]
 
# S→C: [[#Encryption Request|Encryption Request]]
 
# S→C: [[#Encryption Request|Encryption Request]]
# Client auth
+
# Client auth (if enabled)
 
# C→S: [[#Encryption Response|Encryption Response]]
 
# C→S: [[#Encryption Response|Encryption Response]]
# Server auth, both enable encryption
+
# Server auth (if enabled)
 +
# Both enable encryption
 
# S→C: [[#Set Compression|Set Compression]] (optional)
 
# S→C: [[#Set Compression|Set Compression]] (optional)
 
# S→C: [[#Login Success|Login Success]]
 
# S→C: [[#Login Success|Login Success]]
Line 288: Line 309:
 
Set Compression, if present, must be sent before Login Success. Note that anything sent after Set Compression must use the [[#With compression|Post Compression packet format]].
 
Set Compression, if present, must be sent before Login Success. Note that anything sent after Set Compression must use the [[#With compression|Post Compression packet format]].
  
For unauthenticated ("cracked"/offline-mode) and integrated servers (either of the two conditions is enough for an unencrypted connection) there is no encryption. In that case [[#Login Start|Login Start]] is directly followed by [[#Login Success|Login Success]]. The Notchian server uses UUID v3 for offline player UUIDs, with the namespace “OfflinePlayer” and the value as the player’s username. For example, Notch’s offline UUID would be derived from the string “OfflinePlayer:Notch”. This is not a requirement however, the UUID may be anything.
+
Three modes of operation are possible depending on how the packets are sent:
 +
* Online-mode with encryption
 +
* Offline-mode with encryption
 +
* Offline-mode without encryption
 +
 
 +
For online-mode servers (the ones with authentication enabled), encryption is always mandatory, and the entire process described above needs to be followed.
 +
 
 +
For offline-mode servers (the ones with authentication disabled), encryption is optional, and part of the process can be skipped. In that case [[#Login Start|Login Start]] is directly followed by [[#Login Success|Login Success]]. The Notchian server only uses UUID v3 for offline player UUIDs, deriving it from the string <code>OfflinePlayer:<player's name></code> For example, Notch’s offline UUID would be chosen from the string <code>OfflinePlayer:Notch</code>. This is not a requirement however, the UUID can be set to anything.
 +
 
 +
As of 1.21, the Notchian server never uses encryption in offline mode.
  
 
See [[Protocol Encryption]] for details.
 
See [[Protocol Encryption]] for details.
Line 304: Line 334:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | 0x00
+
  | ''protocol:''<br/><code>0x00</code><br/><br/>''resource:''<br/><code>login_disconnect</code>
 
  | Login
 
  | Login
 
  | Client
 
  | Client
 
  | Reason
 
  | Reason
  | [[Chat]]
+
  | {{Type|JSON Text Component}}
 
  | The reason why the player was disconnected.
 
  | The reason why the player was disconnected.
 
  |}
 
  |}
Line 322: Line 352:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="5"| 0x01
+
  | rowspan="6"| ''protocol:''<br/><code>0x01</code><br/><br/>''resource:''<br/><code>hello</code>
  | rowspan="5"| Login
+
  | rowspan="6"| Login
  | rowspan="5"| Client
+
  | rowspan="6"| Client
 
  | Server ID
 
  | Server ID
  | String (20)
+
  | {{Type|String}} (20)
 
  | Appears to be empty.
 
  | Appears to be empty.
 
  |-
 
  |-
 
  | Public Key Length
 
  | Public Key Length
  | VarInt
+
  | {{Type|VarInt}}
  | Length of Public Key
+
  | Length of Public Key.
 
  |-
 
  |-
 
  | Public Key
 
  | Public Key
  | Byte Array
+
  | {{Type|Byte Array}}
 
  | The server's public key, in bytes.
 
  | The server's public key, in bytes.
 
  |-
 
  |-
 
  | Verify Token Length
 
  | Verify Token Length
  | VarInt
+
  | {{Type|VarInt}}
 
  | Length of Verify Token. Always 4 for Notchian servers.
 
  | Length of Verify Token. Always 4 for Notchian servers.
 
  |-
 
  |-
 
  | Verify Token
 
  | Verify Token
  | Byte Array
+
  | {{Type|Byte Array}}
 
  | A sequence of random bytes generated by the server.
 
  | A sequence of random bytes generated by the server.
 +
|-
 +
| Should authenticate
 +
| {{Type|Boolean}}
 +
| Whether the client should attempt to [[Protocol_Encryption#Authentication|authenticate through mojang servers]].
 
  |}
 
  |}
  
Line 358: Line 392:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="7"| 0x02
+
  | rowspan="8"| ''protocol:''<br/><code>0x02</code><br/><br/>''resource:''<br/><code>game_profile</code>
  | rowspan="7"| Login
+
  | rowspan="8"| Login
  | rowspan="7"| Client
+
  | rowspan="8"| Client
| colspan="2"| UUID
 
 
  | colspan="2"| UUID
 
  | colspan="2"| UUID
 +
| colspan="2"| {{Type|UUID}}
 
  | colspan="2"|
 
  | colspan="2"|
 
  |-
 
  |-
 
  | colspan="2"| Username
 
  | colspan="2"| Username
  | colspan="2"| String (16)
+
  | colspan="2"| {{Type|String}} (16)
 
  | colspan="2"|
 
  | colspan="2"|
 
  |-
 
  |-
 
  | colspan="2"| Number Of Properties
 
  | colspan="2"| Number Of Properties
  | colspan="2"| VarInt
+
  | colspan="2"| {{Type|VarInt}}
 
  | Number of elements in the following array.
 
  | Number of elements in the following array.
 
  |-
 
  |-
 
  | rowspan="4"| Property
 
  | rowspan="4"| Property
 
  | Name
 
  | Name
  | rowspan="4"| Array
+
  | rowspan="4"| {{Type|Array}}
  | String (32767)
+
  | {{Type|String}} (32767)
 
  | colspan="2"|
 
  | colspan="2"|
 
  |-
 
  |-
 
  | Value
 
  | Value
  | String (32767)
+
  | {{Type|String}} (32767)
 
  | colspan="1"|
 
  | colspan="1"|
 
  |-
 
  |-
 
  | Is Signed
 
  | Is Signed
  | Boolean
+
  | {{Type|Boolean}}
 
  | colspan="2"|
 
  | colspan="2"|
 
  |-
 
  |-
 
  | Signature
 
  | Signature
  | Optional String (32767)
+
  | {{Type|Optional}} {{Type|String}} (32767)
 
  | Only if Is Signed is true.
 
  | Only if Is Signed is true.
 +
|-
 +
| colspan="2"| Strict Error Handling
 +
| colspan="2"| {{Type|Boolean}}
 +
| colspan="2"| Whether the client should immediately disconnect upon a packet processing error. The Notchian client silently ignores them when this flag is false.
 +
{{Warning2|This field was temporarily added in 1.20.5 as a [https://www.minecraft.net/en-us/article/minecraft-java-edition-1-20-5 way to aid modded servers with the transition to the new data pack & registry system], allowing them to tell the client to silently ignore packets containing inconsistent data. '''It will be removed in 1.21.2''', but it is still present as of version 1.21.1.}}
 
  |}
 
  |}
 +
 +
The Property field looks like response of [[Mojang API#UUID to Profile and Skin/Cape]], except using the protocol format instead of JSON. That is, each player will usually have one property with Name being “textures” and Value being a base64-encoded JSON string, as documented at [[Mojang API#UUID to Profile and Skin/Cape]]. An empty properties array is also acceptable, and will cause clients to display the player with one of the two default skins depending their UUID (again, see the Mojang API page).
  
 
==== Set Compression ====
 
==== Set Compression ====
Line 404: Line 445:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | 0x03
+
  | ''protocol:''<br/><code>0x03</code><br/><br/>''resource:''<br/><code>login_compression</code>
 
  | Login
 
  | Login
 
  | Client
 
  | Client
 
  | Threshold
 
  | Threshold
  | VarInt
+
  | {{Type|VarInt}}
 
  | Maximum size of a packet before it is compressed.
 
  | Maximum size of a packet before it is compressed.
 
  |}
 
  |}
Line 426: Line 467:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="3"| 0x04
+
  | rowspan="3"| ''protocol:''<br/><code>0x04</code><br/><br/>''resource:''<br/><code>custom_query</code>
 
  | rowspan="3"| Login
 
  | rowspan="3"| Login
 
  | rowspan="3"| Client
 
  | rowspan="3"| Client
 
  | Message ID
 
  | Message ID
  | VarInt
+
  | {{Type|VarInt}}
 
  | Generated by the server - should be unique to the connection.
 
  | Generated by the server - should be unique to the connection.
 
  |-
 
  |-
 
  | Channel
 
  | Channel
  | Identifier
+
  | {{Type|Identifier}}
 
  | Name of the [[plugin channel]] used to send the data.
 
  | Name of the [[plugin channel]] used to send the data.
 
  |-
 
  |-
 
  | Data
 
  | Data
  | Byte Array (1048576)
+
  | {{Type|Byte Array}} (1048576)
 
  | Any data, depending on the channel. The length of this array must be inferred from the packet length.
 
  | Any data, depending on the channel. The length of this array must be inferred from the packet length.
 
  |}
 
  |}
  
 
In Notchian client, the maximum data length is 1048576 bytes.
 
In Notchian client, the maximum data length is 1048576 bytes.
 +
 +
==== Cookie Request (login) ====
 +
 +
Requests a cookie that was previously stored.
 +
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! colspan="2"| Field Name
 +
! colspan="2"| Field Type
 +
! Notes
 +
|-
 +
| rowspan="1"| ''protocol:''<br/><code>0x05</code><br/><br/>''resource:''<br/><code>cookie_request</code>
 +
| rowspan="1"| Login
 +
| rowspan="1"| Client
 +
| colspan="2"| Key
 +
| colspan="2"| {{Type|Identifier}}
 +
| The identifier of the cookie.
 +
|}
  
 
=== Serverbound ===
 
=== Serverbound ===
Line 456: Line 517:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="2"| 0x00
+
  | rowspan="2"| ''protocol:''<br/><code>0x00</code><br/><br/>''resource:''<br/><code>hello</code>
 
  | rowspan="2"| Login
 
  | rowspan="2"| Login
 
  | rowspan="2"| Server
 
  | rowspan="2"| Server
 
  | Name
 
  | Name
  | String (16)
+
  | {{Type|String}} (16)
 
  | Player's Username.
 
  | Player's Username.
 
  |-
 
  |-
 
  | Player UUID
 
  | Player UUID
  | UUID
+
  | {{Type|UUID}}
  | The UUID of the player logging in. Unused by the Notchian server.
+
  | The {{Type|UUID}} of the player logging in. Unused by the Notchian server.
 
  |}
 
  |}
  
Line 478: Line 539:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="4"| 0x01
+
  | rowspan="4"| ''protocol:''<br/><code>0x01</code><br/><br/>''resource:''<br/><code>key</code>
 
  | rowspan="4"| Login
 
  | rowspan="4"| Login
 
  | rowspan="4"| Server
 
  | rowspan="4"| Server
 
  | Shared Secret Length
 
  | Shared Secret Length
  | VarInt
+
  | {{Type|VarInt}}
 
  | Length of Shared Secret.
 
  | Length of Shared Secret.
 
  |-
 
  |-
 
  | Shared Secret
 
  | Shared Secret
  | Byte Array
+
  | {{Type|Byte Array}}
 
  | Shared Secret value, encrypted with the server's public key.
 
  | Shared Secret value, encrypted with the server's public key.
 
  |-
 
  |-
 
  | Verify Token Length
 
  | Verify Token Length
  | VarInt
+
  | {{Type|VarInt}}
 
  | Length of Verify Token.
 
  | Length of Verify Token.
 
  |-
 
  |-
 
  | Verify Token
 
  | Verify Token
  | Byte Array
+
  | {{Type|Byte Array}}
 
  | Verify Token value, encrypted with the same public key as the shared secret.
 
  | Verify Token value, encrypted with the same public key as the shared secret.
 
  |}
 
  |}
  
See [[Protocol Encryption]] for details. See [[Mojang_API#Player_Certificates]] for an API to get the message signature.
+
See [[Protocol Encryption]] for details.
  
 
==== Login Plugin Response ====
 
==== Login Plugin Response ====
Line 510: Line 571:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="3"| 0x02
+
  | rowspan="3"| ''protocol:''<br/><code>0x02</code><br/><br/>''resource:''<br/><code>custom_query_answer</code>
 
  | rowspan="3"| Login
 
  | rowspan="3"| Login
 
  | rowspan="3"| Server
 
  | rowspan="3"| Server
 
  | Message ID
 
  | Message ID
  | VarInt
+
  | {{Type|VarInt}}
 
  | Should match ID from server.
 
  | Should match ID from server.
 
  |-
 
  |-
 
  | Successful
 
  | Successful
  | Boolean
+
  | {{Type|Boolean}}
 
  | <code>true</code> if the client understood the request, <code>false</code> otherwise. When <code>false</code>, no payload follows.
 
  | <code>true</code> if the client understood the request, <code>false</code> otherwise. When <code>false</code>, no payload follows.
 
  |-
 
  |-
 
  | Data
 
  | Data
  | Optional Byte Array (1048576)
+
  | {{Type|Optional}} {{Type|Byte Array}} (1048576)
 
  | Any data, depending on the channel. The length of this array must be inferred from the packet length.
 
  | Any data, depending on the channel. The length of this array must be inferred from the packet length.
 
  |}
 
  |}
Line 540: Line 601:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | 0x03
+
  | ''protocol:''<br/><code>0x03</code><br/><br/>''resource:''<br/><code>login_acknowledged</code>
 
  | Login
 
  | Login
 
  | Server
 
  | Server
Line 548: Line 609:
 
This packet switches the connection state to [[#Configuration|configuration]].
 
This packet switches the connection state to [[#Configuration|configuration]].
  
== Configuration ==
+
==== Cookie Response (login) ====
 
 
=== Clientbound ===
 
 
 
==== Clientbound Plugin Message (configuration) ====
 
 
 
{{Main|Plugin channels}}
 
 
 
Mods and plugins can use this to send their data. Minecraft itself uses several [[plugin channel]]s. These internal channels are in the <code>minecraft</code> namespace.
 
  
More information on how it works on [https://dinnerbone.com/blog/2012/01/13/minecraft-plugin-channels-messaging/ Dinnerbone's blog]. More documentation about internal and popular registered channels are [[plugin channel|here]].
+
Response to a [[#Cookie_Request_(login)|Cookie Request (login)]] from the server. The Notchian server only accepts responses of up to 5 kiB in size.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 564: Line 617:
 
  ! State
 
  ! State
 
  ! Bound To
 
  ! Bound To
  ! Field Name
+
  ! colspan="2"| Field Name
  ! Field Type
+
  ! colspan="2"| Field Type
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="2"| 0x00
+
  | rowspan="4"| ''protocol:''<br/><code>0x04</code><br/><br/>''resource:''<br/><code>cookie_response</code>
 +
| rowspan="4"| Login
 +
| rowspan="4"| Server
 +
| colspan="2"| Key
 +
| colspan="2"| {{Type|Identifier}}
 +
| The identifier of the cookie.
 +
|-
 +
| colspan="2"| Has Payload
 +
| colspan="2"| {{Type|Boolean}}
 +
| The payload is only present if the cookie exists on the client.
 +
|-
 +
| colspan="2"| Payload Length
 +
| colspan="2"| {{Type|Optional}} {{Type|VarInt}}
 +
| Length of the following byte array.
 +
|-
 +
| colspan="2"| Payload
 +
| colspan="2"| {{Type|Optional}} {{Type|Byte Array}} (5120)
 +
| The data of the cookie, if any.
 +
|}
 +
 
 +
== Configuration ==
 +
 
 +
=== Clientbound ===
 +
 
 +
==== Cookie Request (configuration) ====
 +
 
 +
Requests a cookie that was previously stored.
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! colspan="2"| Field Name
 +
! colspan="2"| Field Type
 +
! Notes
 +
|-
 +
| rowspan="1"| ''protocol:''<br/><code>0x00</code><br/><br/>''resource:''<br/><code>cookie_request</code>
 +
| rowspan="1"| Configuration
 +
| rowspan="1"| Client
 +
| colspan="2"| Key
 +
| colspan="2"| {{Type|Identifier}}
 +
| The identifier of the cookie.
 +
|}
 +
 
 +
==== Clientbound Plugin Message (configuration) ====
 +
 
 +
{{Main|Plugin channels}}
 +
 
 +
Mods and plugins can use this to send their data. Minecraft itself uses several [[plugin channel]]s. These internal channels are in the <code>minecraft</code> namespace.
 +
 
 +
More information on how it works on [https://web.archive.org/web/20220831140929/https://dinnerbone.com/blog/2012/01/13/minecraft-plugin-channels-messaging/ Dinnerbone's blog]. More documentation about internal and popular registered channels are [[plugin channel|here]].
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 +
|-
 +
| rowspan="2"| ''protocol:''<br/><code>0x01</code><br/><br/>''resource:''<br/><code>custom_payload</code>
 
  | rowspan="2"| Configuration
 
  | rowspan="2"| Configuration
 
  | rowspan="2"| Client
 
  | rowspan="2"| Client
 
  | Channel
 
  | Channel
  | Identifier
+
  | {{Type|Identifier}}
 
  | Name of the [[plugin channel]] used to send the data.
 
  | Name of the [[plugin channel]] used to send the data.
 
  |-
 
  |-
 
  | Data
 
  | Data
  | Byte Array (1048576)
+
  | {{Type|Byte Array}} (1048576)
 
  | Any data. The length of this array must be inferred from the packet length.
 
  | Any data. The length of this array must be inferred from the packet length.
 
  |}
 
  |}
Line 592: Line 705:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | 0x01
+
  | ''protocol:''<br/><code>0x02</code><br/><br/>''resource:''<br/><code>disconnect</code>
 
  | Configuration  
 
  | Configuration  
 
  | Client
 
  | Client
 
  | Reason
 
  | Reason
  | [[Chat]]
+
  | {{Type|Text Component}}
 
  | The reason why the player was disconnected.
 
  | The reason why the player was disconnected.
 
  |}
 
  |}
Line 602: Line 715:
 
==== Finish Configuration ====
 
==== Finish Configuration ====
  
Sent by the server to notify the client that the configuration process has finished. The client answers with its own [[#Finish_Configuration_2|Finish Configuration]] whenever it is ready to continue.
+
Sent by the server to notify the client that the configuration process has finished. The client answers with [[#Acknowledge_Finish_Configuration|Acknowledge Finish Configuration]] whenever it is ready to continue.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 612: Line 725:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="1"| 0x02
+
  | rowspan="1"| ''protocol:''<br/><code>0x03</code><br/><br/>''resource:''<br/><code>finish_configuration</code>
 
  | rowspan="1"| Configuration
 
  | rowspan="1"| Configuration
 
  | rowspan="1"| Client
 
  | rowspan="1"| Client
Line 622: Line 735:
 
==== Clientbound Keep Alive (configuration) ====
 
==== Clientbound Keep Alive (configuration) ====
  
The server will frequently send out a keep-alive, each containing a random ID. The client must respond with the same payload (see [[#Serverbound Keep Alive (configuration)|Serverbound Keep Alive]]). If the client does not respond to them for over 30 seconds, the server kicks the client. Vice versa, if the server does not send any keep-alives for 20 seconds, the client will disconnect and yields a "Timed out" exception.
+
The server will frequently send out a keep-alive, each containing a random ID. The client must respond with the same payload (see [[#Serverbound Keep Alive (configuration)|Serverbound Keep Alive]]). If the client does not respond to a Keep Alive packet within 15 seconds after it was sent, the server kicks the client. Vice versa, if the server does not send any keep-alives for 20 seconds, the client will disconnect and yields a "Timed out" exception.
  
 
The Notchian server uses a system-dependent time in milliseconds to generate the keep alive ID value.
 
The Notchian server uses a system-dependent time in milliseconds to generate the keep alive ID value.
Line 634: Line 747:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | 0x03
+
  | ''protocol:''<br/><code>0x04</code><br/><br/>''resource:''<br/><code>keep_alive</code>
 
  | Configuration
 
  | Configuration
 
  | Client
 
  | Client
 
  | Keep Alive ID
 
  | Keep Alive ID
  | Long
+
  | {{Type|Long}}
 
  |
 
  |
 
  |}
 
  |}
Line 654: Line 767:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | 0x04
+
  | ''protocol:''<br/><code>0x05</code><br/><br/>''resource:''<br/><code>ping</code>
 
  | Configuration
 
  | Configuration
 
  | Client
 
  | Client
 
  | ID
 
  | ID
  | Int
+
  | {{Type|Int}}
 
  |
 
  |
 
  |}
 
  |}
  
==== Registry Data ====
+
==== Reset Chat ====
 
 
Represents certain registries that are sent from the server and are applied on the client.
 
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 674: Line 785:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="1"| 0x05
+
  | ''protocol:''<br/><code>0x06</code><br/><br/>''resource:''<br/><code>reset_chat</code>
  | rowspan="1"| Configuration
+
  | Configuration
  | rowspan="1"| Client
+
  | Client
  | Registry Codec
+
  | colspan="3"| ''no fields''
| [[NBT|NBT Tag Compound]]
 
| See [[Registry Data]].
 
 
  |}
 
  |}
  
==== Resource Pack (configuration) ====
+
==== Registry Data ====
 +
 
 +
Represents certain registries that are sent from the server and are applied on the client.
 +
 
 +
See [[Registry_Data|Registry Data]] for details.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 688: Line 801:
 
  ! State
 
  ! State
 
  ! Bound To
 
  ! Bound To
  ! Field Name
+
  ! colspan="2"| Field Name
  ! Field Type
+
  ! colspan="2"| Field Type
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="5"| 0x06
+
  | rowspan="6"| ''protocol:''<br/><code>0x07</code><br/><br/>''resource:''<br/><code>registry_data</code>
  | rowspan="5"| Configuration
+
  | rowspan="6"| Configuration
  | rowspan="5"| Client
+
  | rowspan="6"| Client
  | URL
+
  |-
  | String (32767)
+
| colspan="2"| Registry ID
  | The URL to the resource pack.
+
  | colspan="2"| {{Type|Identifier}}
 +
  |  
 
  |-
 
  |-
  | Hash
+
  | colspan="2"| Entry Count
  | String (40)
+
  | colspan="2"| {{Type|VarInt}}
  | A 40 character hexadecimal and lowercase [[wikipedia:SHA-1|SHA-1]] hash of the resource pack file.<br />If it's not a 40 character hexadecimal string, the client will not use it for hash verification and likely waste bandwidth — but it will still treat it as a unique id
+
  | Number of entries in the following array.
 
  |-
 
  |-
  | Forced
+
  | rowspan="3"| Entries
  | Boolean
+
| Entry ID
  | The notchian client will be forced to use the resource pack from the server. If they decline they will be kicked from the server.
+
| rowspan="3"| {{Type|Array}}
 +
  | {{Type|Identifier}}
 +
  |
 
  |-
 
  |-
  | Has Prompt Message
+
  | Has Data
  | Boolean
+
  | {{Type|Boolean}}
  | <code>true</code> If the next field will be sent <code>false</code> otherwise. When <code>false</code>, this is the end of the packet
+
  | Whether the entry has any data following.
 
  |-
 
  |-
  | Prompt Message
+
  | Data
  | Optional [[Chat]]
+
  | {{Type|NBT}}
  | This is shown in the prompt making the client accept or decline the resource pack.
+
  | Entry data. Only present if Has Data is true.
 
  |}
 
  |}
  
==== Feature Flags ====
+
==== Remove Resource Pack (configuration) ====
 
 
Used to enable and disable features, generally experimental ones, on the client.
 
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 728: Line 842:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="2"| 0x07
+
  | rowspan="2"| ''protocol:''<br/><code>0x08</code><br/><br/>''resource:''<br/><code>resource_pack_pop</code>
 
  | rowspan="2"| Configuration
 
  | rowspan="2"| Configuration
 
  | rowspan="2"| Client
 
  | rowspan="2"| Client
  | Total Features
+
  | Has UUID
  | VarInt
+
  | {{Type|Boolean}}
  | Number of features that appear in the array below.
+
  | Whether a specific resource pack should be removed, or all of them.
 
  |-
 
  |-
  | Feature Flags
+
  | UUID
  | Identifier Array
+
  | {{Type|Optional}} {{Type|UUID}}
  |
+
  | The {{Type|UUID}} of the resource pack to be removed. Only present if the previous field is true.
 
  |}
 
  |}
  
As of 1.20.2, the following feature flags are available:
+
==== Add Resource Pack (configuration) ====
  
* minecraft:vanilla - enables vanilla features</li>
+
{| class="wikitable"
* minecraft:bundle - enables support for the bundle</li>
+
! Packet ID
* minecraft:trade_rebalance - enables support for the rebalanced villager trades</li>
+
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 +
|-
 +
| rowspan="6"| ''protocol:''<br/><code>0x09</code><br/><br/>''resource:''<br/><code>resource_pack_push</code>
 +
| rowspan="6"| Configuration
 +
| rowspan="6"| Client
 +
| UUID
 +
| {{Type|UUID}}
 +
| The unique identifier of the resource pack.
 +
|-
 +
| URL
 +
| {{Type|String}} (32767)
 +
| The URL to the resource pack.
 +
|-
 +
| Hash
 +
| {{Type|String}} (40)
 +
| A 40 character hexadecimal, case-insensitive [[wikipedia:SHA-1|SHA-1]] hash of the resource pack file.<br />If it's not a 40 character hexadecimal string, the client will not use it for hash verification and likely waste bandwidth.
 +
|-
 +
| Forced
 +
| {{Type|Boolean}}
 +
| The Notchian client will be forced to use the resource pack from the server. If they decline they will be kicked from the server.
 +
|-
 +
| Has Prompt Message
 +
| {{Type|Boolean}}
 +
| Whether a custom message should be used on the resource pack prompt.
 +
|-
 +
| Prompt Message
 +
| {{Type|Optional}} {{Type|Text Component}}
 +
| This is shown in the prompt making the client accept or decline the resource pack. Only present if the previous field is true.
 +
|}
 +
 
 +
==== Store Cookie (configuration) ====
  
==== Update Tags ====
+
Stores some arbitrary data on the client, which persists between server transfers. The Notchian client only accepts cookies of up to 5 kiB in size.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 756: Line 904:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="3"| 0x08
+
  | rowspan="3"| ''protocol:''<br/><code>0x0A</code><br/><br/>''resource:''<br/><code>store_cookie</code>
 
  | rowspan="3"| Configuration
 
  | rowspan="3"| Configuration
 
  | rowspan="3"| Client
 
  | rowspan="3"| Client
  | colspan="2"| Length of the array
+
  | colspan="2"| Key
  | colspan="2"| VarInt
+
  | colspan="2"| {{Type|Identifier}}
  |
+
  | The identifier of the cookie.
 
  |-
 
  |-
  | rowspan="2"| Array of tags
+
  | colspan="2"| Payload Length
| Tag type
+
  | colspan="2"| {{Type|VarInt}}
  | rowspan="2"| Array
+
  | Length of the following byte array.
| Identifier
 
  | Tag identifier (Vanilla required tags are <code>minecraft:block</code>, <code>minecraft:item</code>, <code>minecraft:fluid</code>, <code>minecraft:entity_type</code>, and <code>minecraft:game_event</code>)
 
 
  |-
 
  |-
  | Array of Tag
+
  | colspan="2"| Payload
  | (See below)
+
  | colspan="2"| {{Type|Byte Array}} (5120)
  |
+
  | The data of the cookie.
 
  |}
 
  |}
  
Tag arrays look like:
+
==== Transfer (configuration) ====
 +
 
 +
Notifies the client that it should transfer to the given server. Cookies previously stored are preserved between server transfers.
  
 
{| class="wikitable"
 
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 
  ! colspan="2"| Field Name
 
  ! colspan="2"| Field Name
 
  ! colspan="2"| Field Type
 
  ! colspan="2"| Field Type
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | colspan="2"| Length
+
| rowspan="2"| ''protocol:''<br/><code>0x0B</code><br/><br/>''resource:''<br/><code>transfer</code>
  | colspan="2"| VarInt
+
| rowspan="2"| Configuration
  | Number of elements in the following array
+
| rowspan="2"| Client
 +
  | colspan="2"| Host
 +
  | colspan="2"| {{Type|String}}
 +
  | The hostname or IP of the server.
 
  |-
 
  |-
  | rowspan="3"| Tags
+
  | colspan="2"| Port
  | Tag name
+
  | colspan="2"| {{Type|VarInt}}
| rowspan="3"| Array
+
  | The port of the server.
| Identifier
 
|
 
|-
 
| Count
 
| VarInt
 
| Number of elements in the following array
 
|-
 
| Entries
 
| Array of VarInt
 
  | Numeric ID of the given type (block, item, etc.).
 
 
  |}
 
  |}
  
More information on tags is available at: https://minecraft.wiki/w/Tag
+
==== Feature Flags ====
  
And a list of all tags is here: https://minecraft.wiki/w/Tag#List_of_tags
+
Used to enable and disable features, generally experimental ones, on the client.
 
 
=== Serverbound ===
 
 
 
==== Client Information (configuration) ====
 
 
 
Sent when the player connects, or when settings are changed.
 
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 818: Line 956:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="8"| 0x00
+
  | rowspan="2"| ''protocol:''<br/><code>0x0C</code><br/><br/>''resource:''<br/><code>update_enabled_features</code>
  | rowspan="8"| Configuration
+
  | rowspan="2"| Configuration
  | rowspan="8"| Server
+
  | rowspan="2"| Client
  | Locale
+
  | Total Features
  | String (16)
+
  | {{Type|VarInt}}
  | e.g. <code>en_GB</code>.
+
  | Number of features that appear in the array below.
 
  |-
 
  |-
  | View Distance
+
  | Feature Flags
  | Byte
+
  | {{Type|Array}} of {{Type|Identifier}}
| Client-side render distance, in chunks.
+
  |
|-
 
| Chat Mode
 
| VarInt Enum
 
| 0: enabled, 1: commands only, 2: hidden.  See [[Chat#Processing chat|processing chat]] for more information.
 
|-
 
| Chat Colors
 
| Boolean
 
| “Colors” multiplayer setting. Can the chat be colored?
 
|-
 
| Displayed Skin Parts
 
| Unsigned Byte
 
| Bit mask, see below.
 
|-
 
| Main Hand
 
| VarInt Enum
 
| 0: Left, 1: Right.
 
|-
 
| Enable text filtering
 
| Boolean
 
| Enables filtering of text on signs and written book titles. Currently always false (i.e. the filtering is disabled)
 
|-
 
| Allow server listings
 
| Boolean
 
  | Servers usually list online players, this option should let you not show up in that list.
 
 
  |}
 
  |}
  
''Displayed Skin Parts'' flags:
+
As of 1.21, the following feature flags are available:
  
* Bit 0 (0x01): Cape enabled
+
* minecraft:vanilla - enables vanilla features</li>
* Bit 1 (0x02): Jacket enabled
+
* minecraft:bundle - enables support for the bundle</li>
* Bit 2 (0x04): Left Sleeve enabled
+
* minecraft:trade_rebalance - enables support for the rebalanced villager trades</li>
* Bit 3 (0x08): Right Sleeve enabled
 
* Bit 4 (0x10): Left Pants Leg enabled
 
* Bit 5 (0x20): Right Pants Leg enabled
 
* Bit 6 (0x40): Hat enabled
 
  
The most significant bit (bit 7, 0x80) appears to be unused.
+
==== Update Tags (configuration) ====
 
 
==== Serverbound Plugin Message (configuration) ====
 
 
 
{{Main|Plugin channels}}
 
 
 
Mods and plugins can use this to send their data. Minecraft itself uses some [[plugin channel]]s. These internal channels are in the <code>minecraft</code> namespace.
 
 
 
More documentation on this: [https://dinnerbone.com/blog/2012/01/13/minecraft-plugin-channels-messaging/ https://dinnerbone.com/blog/2012/01/13/minecraft-plugin-channels-messaging/]
 
 
 
Note that the length of Data is known only from the packet length, since the packet has no length field of any kind.
 
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 880: Line 980:
 
  ! State
 
  ! State
 
  ! Bound To
 
  ! Bound To
  ! Field Name
+
  ! colspan="2"| Field Name
  ! Field Type
+
  ! colspan="2"| Field Type
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="2"| 0x01
+
  | rowspan="3"| ''protocol:''<br/><code>0x0D</code><br/><br/>''resource:''<br/><code>update_tags</code>
  | rowspan="2"| Configuration
+
| rowspan="3"| Configuration
  | rowspan="2"| Server
+
| rowspan="3"| Client
  | Channel
+
| colspan="2"| Length of the array
  | Identifier
+
  | colspan="2"| {{Type|VarInt}}
  | Name of the [[plugin channel]] used to send the data.
+
|
 +
|-
 +
  | rowspan="2"| Array of tags
 +
| Registry
 +
  | rowspan="2"| {{Type|Array}}
 +
  | {{Type|Identifier}}
 +
  | Registry identifier (Vanilla expects tags for the registries <code>minecraft:block</code>, <code>minecraft:item</code>, <code>minecraft:fluid</code>, <code>minecraft:entity_type</code>, and <code>minecraft:game_event</code>)
 
  |-
 
  |-
  | Data
+
  | Array of Tag
  | Byte Array (32767)
+
  | (See below)
  | Any data, depending on the channel. <code>minecraft:</code> channels are documented [[plugin channel|here]]. The length of this array must be inferred from the packet length.
+
  |
 
  |}
 
  |}
  
In Notchian server, the maximum data length is 32767 bytes.
+
Tag arrays look like:
 
 
==== Finish Configuration ====
 
 
 
Sent by the client to notify the client that the configuration process has finished. It is sent in response to the server's [[#Finish_Configuration|Finish Configuration]].
 
  
 
{| class="wikitable"
 
{| class="wikitable"
  ! Packet ID
+
  ! colspan="2"| Field Name
! State
+
  ! colspan="2"| Field Type
! Bound To
 
! Field Name
 
  ! Field Type
 
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="1"| 0x02
+
  | colspan="2"| Length
  | rowspan="1"| Configuration
+
  | colspan="2"| {{Type|VarInt}}
  | rowspan="1"| Server
+
| Number of elements in the following array
  | colspan="3"| ''no fields''
+
|-
 +
  | rowspan="3"| Tags
 +
| Tag name
 +
  | rowspan="3"| {{Type|Array}}
 +
| {{Type|Identifier}}
 +
|
 +
|-
 +
| Count
 +
| {{Type|VarInt}}
 +
| Number of elements in the following array
 +
|-
 +
| Entries
 +
| {{Type|Array}} of {{Type|VarInt}}
 +
| Numeric IDs of the given type (block, item, etc.). This list replaces the previous list of IDs for the given tag. If some preexisting tags are left unmentioned, a warning is printed.
 
  |}
 
  |}
  
This packet switches the connection state to [[#Play|play]].
+
See {{Minecraft Wiki|Tag}} on the Minecraft Wiki for more information, including a list of vanilla tags.
 +
 
 +
==== Clientbound Known Packs ====
  
==== Serverbound Keep Alive (configuration) ====
+
Informs the client of which data packs are present on the server.
 +
The client is expected to respond with its own [[#Serverbound_Known_Packs|Serverbound Known Packs]] packet.
 +
The Notchian server does not continue with Configuration until it receives a response.
  
The server will frequently send out a keep-alive (see [[#Clientbound Keep Alive (configuration)|Clientbound Keep Alive]]), each containing a random ID. The client must respond with the same packet.
+
The Notchian client requires the <code>minecraft:core</code> pack with version <code>1.21</code> for a normal login sequence. This packet must be sent before the Registry Data packets.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 926: Line 1,042:
 
  ! State
 
  ! State
 
  ! Bound To
 
  ! Bound To
  ! Field Name
+
  ! colspan="2"| Field Name
  ! Field Type
+
  ! colspan="2"| Field Type
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | 0x03
+
  | rowspan="4"| ''protocol:''<br/><code>0x0E</code><br/><br/>''resource:''<br/><code>select_known_packs</code>
  | Configuration
+
  | rowspan="4"| Configuration
  | Server
+
  | rowspan="4"| Client
  | Keep Alive ID
+
| colspan="2"| Known Pack Count
  | Long
+
| colspan="2"| {{Type|VarInt}}
 +
| The number of known packs in the following array.
 +
|-
 +
| rowspan="3"| Known Packs
 +
| Namespace
 +
| rowspan="3"| {{Type|Array}}
 +
| {{Type|String}}
 +
|
 +
|-
 +
  | ID
 +
  | {{Type|String}}
 +
|
 +
|-
 +
| Version
 +
| {{Type|String}}
 
  |
 
  |
 
  |}
 
  |}
  
==== Pong (configuration) ====
+
==== Custom Report Details (configuration) ====
  
Response to the clientbound packet ([[#Ping (configuration)|Ping]]) with the same id.
+
Contains a list of key-value text entries that are included in any crash or disconnection report generated during connection to the server.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 946: Line 1,076:
 
  ! State
 
  ! State
 
  ! Bound To
 
  ! Bound To
  ! Field Name
+
  ! colspan="2"| Field Name
  ! Field Type
+
  ! colspan="2"| Field Type
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | 0x04
+
  | rowspan="3"| ''protocol:''<br/><code>0x0F</code><br/><br/>''resource:''<br/><code>custom_report_details</code>
  | Configuration
+
  | rowspan="3"| Configuration
  | Server
+
  | rowspan="3"| Client
  | ID
+
  | colspan="2"| Details Count
  | Int
+
  | colspan="2"| {{Type|VarInt}} (32)
  | id is the same as the ping packet
+
  | The number of details in the following array.
  |}
+
|-
 +
| rowspan="2"| Details
 +
| Title
 +
| rowspan="2"| {{Type|Array}}
 +
| {{Type|String}} (128)
 +
|
 +
|-
 +
| Description
 +
| {{Type|String}} (4096)
 +
  |
 +
|}
 +
 
 +
==== Server Links (configuration) ====
  
==== Resource Pack Response (configuration) ====
+
This packet contains a list of links that the Notchian client will display in the menu available from the pause menu. Link labels can be built-in or custom (i.e., any text).
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 964: Line 1,106:
 
  ! State
 
  ! State
 
  ! Bound To
 
  ! Bound To
  ! Field Name
+
  ! colspan="2"| Field Name
  ! Field Type
+
  ! colspan="2"| Field Type
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | 0x05
+
  | rowspan="4"| ''protocol:''<br/><code>0x10</code><br/><br/>''resource:''<br/><code>server_links</code>
  | Configuration
+
  | rowspan="4"| Configuration
  | Server
+
  | rowspan="4"| Client
  | Result
+
  | colspan="2"| Links Count
  | VarInt Enum
+
  | colspan="2"| {{Type|VarInt}}
  | 0: successfully loaded, 1: declined, 2: failed download, 3: accepted.
+
| The number of links in the following array.
  |}
+
|-
 +
| rowspan="3"| Links
 +
| Is built-in
 +
| rowspan="3"| {{Type|Array}}
 +
| {{Type|Boolean}}
 +
| True if Label is an enum (built-in label), false if it's a text component (custom label).
 +
|-
 +
| Label
 +
| {{Type|VarInt}} {{Type|Enum}} / {{Type|Text Component}}
 +
  | See below.
 +
  |-
 +
| URL
 +
| {{Type|String}}
 +
| Valid URL.
 +
|}
  
== Play ==
 
  
=== Clientbound ===
+
{| class="wikitable"
 +
! ID
 +
! Name
 +
! Notes
 +
|-
 +
| 0
 +
| Bug Report
 +
| Displayed on connection error screen; included as a comment in the disconnection report.
 +
|-
 +
| 1
 +
| Community Guidelines
 +
|
 +
|-
 +
| 2
 +
| Support
 +
|
 +
|-
 +
| 3
 +
| Status
 +
|
 +
|-
 +
| 4
 +
| Feedback
 +
|
 +
|-
 +
| 5
 +
| Community
 +
|
 +
|-
 +
| 6
 +
| Website
 +
|
 +
|-
 +
| 7
 +
| Forums
 +
|
 +
|-
 +
| 8
 +
| News
 +
|
 +
|-
 +
| 9
 +
| Announcements
 +
|
 +
|-
 +
|}
  
==== Bundle Delimiter ====
+
=== Serverbound ===
  
The delimiter for a bundle of packets. When received, the client should store every subsequent packet it receives, and wait until another delimiter is received. Once that happens, the client is guaranteed to process every packet in the bundle on the same tick, and the client should stop storing packets. For example, this is used to ensure [[#Spawn_Entity|Spawn Entity]] and [[#Set_Entity_Metadata|Set Entity Metadata]] happen on the same tick.
+
==== Client Information (configuration) ====
  
The Notchian client doesn't allow more than 4096 packets in the same bundle.
+
Sent when the player connects, or when settings are changed.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 994: Line 1,194:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | 0x00
+
  | rowspan="8"| ''protocol:''<br/><code>0x00</code><br/><br/>''resource:''<br/><code>client_information</code>
  | Play
+
  | rowspan="8"| Configuration
  | Client
+
  | rowspan="8"| Server
  | colspan="3"| ''no fields''
+
| Locale
|}
+
| {{Type|String}} (16)
 +
| e.g. <code>en_GB</code>.
 +
|-
 +
| View Distance
 +
| {{Type|Byte}}
 +
| Client-side render distance, in chunks.
 +
|-
 +
| Chat Mode
 +
| {{Type|VarInt}} {{Type|Enum}}
 +
| 0: enabled, 1: commands only, 2: hidden.  See [[Chat#Client chat mode]] for more information.
 +
|-
 +
| Chat Colors
 +
| {{Type|Boolean}}
 +
| “Colors” multiplayer setting. Can the chat be colored?
 +
|-
 +
| Displayed Skin Parts
 +
| {{Type|Unsigned Byte}}
 +
  | Bit mask, see below.
 +
|-
 +
| Main Hand
 +
| {{Type|VarInt}} {{Type|Enum}}
 +
| 0: Left, 1: Right.
 +
|-
 +
| Enable text filtering
 +
| {{Type|Boolean}}
 +
| Enables filtering of text on signs and written book titles. Currently always false (i.e. the filtering is disabled)
 +
|-
 +
| Allow server listings
 +
| {{Type|Boolean}}
 +
| Servers usually list online players, this option should let you not show up in that list.
 +
|}
 +
 
 +
''Displayed Skin Parts'' flags:
  
==== Spawn Entity ====
+
* Bit 0 (0x01): Cape enabled
 +
* Bit 1 (0x02): Jacket enabled
 +
* Bit 2 (0x04): Left Sleeve enabled
 +
* Bit 3 (0x08): Right Sleeve enabled
 +
* Bit 4 (0x10): Left Pants Leg enabled
 +
* Bit 5 (0x20): Right Pants Leg enabled
 +
* Bit 6 (0x40): Hat enabled
 +
 
 +
The most significant bit (bit 7, 0x80) appears to be unused.
 +
 
 +
==== Cookie Response (configuration) ====
  
Sent by the server when an entity (aside from [[#Spawn_Experience_Orb|Experince Orb]]) is created.
+
Response to a [[#Cookie_Request_(configuration)|Cookie Request (configuration)]] from the server. The Notchian server only accepts responses of up to 5 kiB in size.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 1,008: Line 1,250:
 
  ! State
 
  ! State
 
  ! Bound To
 
  ! Bound To
  ! Field Name
+
  ! colspan="2"| Field Name
  ! Field Type
+
  ! colspan="2"| Field Type
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="13"| 0x01
+
  | rowspan="4"| ''protocol:''<br/><code>0x01</code><br/><br/>''resource:''<br/><code>cookie_response</code>
  | rowspan="13"| Play
+
  | rowspan="4"| Configuration
  | rowspan="13"| Client
+
  | rowspan="4"| Server
  | Entity ID
+
  | colspan="2"| Key
| VarInt
+
  | colspan="2"| {{Type|Identifier}}
  | A unique integer ID mostly used in the protocol to identify the entity.
+
  | The identifier of the cookie.
|-
 
| Entity UUID
 
| UUID
 
  | A unique identifier that is mostly used in persistence and places where the uniqueness matters more.
 
 
  |-
 
  |-
  | Type
+
  | colspan="2"| Has Payload
  | VarInt
+
  | colspan="2"| {{Type|Boolean}}
  | The type of the entity (see "type" field of the list of [[entity_metadata#Mobs|Mob types]]).
+
  | The payload is only present if the cookie exists on the client.
 
  |-
 
  |-
  | X
+
  | colspan="2"| Payload Length
  | Double
+
  | colspan="2"| {{Type|Optional}} {{Type|VarInt}}
  |
+
  | Length of the following byte array.
 
  |-
 
  |-
  | Y
+
  | colspan="2"| Payload
  | Double
+
  | colspan="2"| {{Type|Optional}} {{Type|Byte Array}} (5120)
  |
+
  | The data of the cookie, if any.
 +
|}
 +
 
 +
==== Serverbound Plugin Message (configuration) ====
 +
 
 +
{{Main|Plugin channels}}
 +
 
 +
Mods and plugins can use this to send their data. Minecraft itself uses some [[plugin channel]]s. These internal channels are in the <code>minecraft</code> namespace.
 +
 
 +
More documentation on this: [https://dinnerbone.com/blog/2012/01/13/minecraft-plugin-channels-messaging/ https://dinnerbone.com/blog/2012/01/13/minecraft-plugin-channels-messaging/]
 +
 
 +
Note that the length of Data is known only from the packet length, since the packet has no length field of any kind.
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 
  |-
 
  |-
  | Z
+
  | rowspan="2"| ''protocol:''<br/><code>0x02</code><br/><br/>''resource:''<br/><code>custom_payload</code>
| Double
+
  | rowspan="2"| Configuration
|
+
  | rowspan="2"| Server
|-
+
  | Channel
| Pitch
+
  | {{Type|Identifier}}
| Angle
+
  | Name of the [[plugin channel]] used to send the data.
| To get the real pitch, you must divide this by (256.0F / 360.0F)
 
  |-
 
| Yaw
 
  | Angle
 
| To get the real yaw, you must divide this by (256.0F / 360.0F)
 
  |-
 
  | Head Yaw
 
| Angle
 
  | Only used by living entities, where the head of the entity may differ from the general body rotation.
 
 
  |-
 
  |-
 
  | Data
 
  | Data
  | VarInt
+
  | {{Type|Byte Array}} (32767)
  | Meaning dependent on the value of the Type field, see [[Object Data]] for details.
+
  | Any data, depending on the channel. <code>minecraft:</code> channels are documented [[plugin channel|here]]. The length of this array must be inferred from the packet length.
|-
 
| Velocity X
 
| Short
 
| rowspan="3"| Same units as [[#Set Entity Velocity|Set Entity Velocity]].
 
|-
 
| Velocity Y
 
| Short
 
|-
 
| Velocity Z
 
| Short
 
 
  |}
 
  |}
  
{{Warning2|The points listed below should be considered when this packet is used to spawn a player entity.}}
+
In Notchian server, the maximum data length is 32767 bytes.
When in {{Minecraft Wiki|Server.properties#online-mode|online mode}}, the UUIDs must be valid and have valid skin blobs.
 
In offline mode, [[Wikipedia:Universally unique identifier#Versions 3 and 5 (namespace name-based)|UUID v3]] is used with the String <code>OfflinePlayer:&lt;player name&gt;</code>, encoded in UTF-8 (and case-sensitive). The Notchian server uses <code>UUID.nameUUIDFromBytes</code>, implemented by OpenJDK [https://github.com/AdoptOpenJDK/openjdk-jdk8u/blob/9a91972c76ddda5c1ce28b50ca38cbd8a30b7a72/jdk/src/share/classes/java/util/UUID.java#L153-L175 here].
 
 
 
For NPCs UUID v2 should be used. Note:
 
 
 
<+Grum> i will never confirm this as a feature you know that :)
 
  
In an example UUID, <code>xxxxxxxx-xxxx-Yxxx-xxxx-xxxxxxxxxxxx</code>, the UUID version is specified by <code>Y</code>. So, for UUID v3, <code>Y</code> will always be <code>3</code>, and for UUID v2, <code>Y</code> will always be <code>2</code>.
+
==== Acknowledge Finish Configuration ====
 
 
==== Spawn Experience Orb ====
 
  
Spawns one or more experience orbs.
+
Sent by the client to notify the server that the configuration process has finished. It is sent in response to the server's [[#Finish_Configuration|Finish Configuration]].
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 1,088: Line 1,318:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="5"| 0x02
+
  | rowspan="1"| ''protocol:''<br/><code>0x03</code><br/><br/>''resource:''<br/><code>finish_configuration</code>
  | rowspan="5"| Play
+
  | rowspan="1"| Configuration
  | rowspan="5"| Client
+
  | rowspan="1"| Server
  | Entity ID
+
  | colspan="3"| ''no fields''
| VarInt
 
|
 
|-
 
| X
 
| Double
 
|
 
|-
 
| Y
 
| Double
 
|
 
|-
 
| Z
 
| Double
 
|
 
|-
 
| Count
 
| Short
 
| The amount of experience this orb will reward once collected.
 
 
  |}
 
  |}
  
==== Entity Animation ====
+
This packet switches the connection state to [[#Play|play]].
 +
 
 +
==== Serverbound Keep Alive (configuration) ====
  
Sent whenever an entity should change animation.
+
The server will frequently send out a keep-alive (see [[#Clientbound Keep Alive (configuration)|Clientbound Keep Alive]]), each containing a random ID. The client must respond with the same packet.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 1,124: Line 1,338:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="2"| 0x03
+
  | ''protocol:''<br/><code>0x04</code><br/><br/>''resource:''<br/><code>keep_alive</code>
| rowspan="2"| Play
+
  | Configuration
| rowspan="2"| Client
+
  | Server
  | Entity ID
+
  | Keep Alive ID
  | VarInt
+
  | {{Type|Long}}
  | Player ID.
+
  |
|-
 
  | Animation
 
| Unsigned Byte
 
  | Animation ID (see below).
 
 
  |}
 
  |}
  
Animation can be one of the following values:
+
==== Pong (configuration) ====
  
{| class="wikitable"
+
Response to the clientbound packet ([[#Ping (configuration)|Ping]]) with the same id.
! ID
 
! Animation
 
|-
 
| 0
 
| Swing main arm
 
|-
 
| 2
 
| Leave bed
 
|-
 
| 3
 
| Swing offhand
 
|-
 
| 4
 
| Critical effect
 
|-
 
| 5
 
| Magic critical effect
 
|}
 
 
 
==== Award Statistics ====
 
 
 
Sent as a response to [[#Client Command|Client Command]] (id 1). Will only send the changed values if previously requested.
 
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 1,166: Line 1,354:
 
  ! State
 
  ! State
 
  ! Bound To
 
  ! Bound To
  ! colspan="2"| Field Name
+
  ! Field Name
  ! colspan="2"| Field Type
+
  ! Field Type
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="4"| 0x04
+
  | ''protocol:''<br/><code>0x05</code><br/><br/>''resource:''<br/><code>pong</code>
  | rowspan="4"| Play
+
| Configuration
  | rowspan="4"| Client
+
  | Server
  | colspan="2"| Count
+
| ID
| colspan="2"| VarInt
+
  | {{Type|Int}}
  | Number of elements in the following array.
+
| id is the same as the ping packet
 +
  |}
 +
 
 +
==== Resource Pack Response (configuration) ====
 +
 
 +
{| class="wikitable"
 +
  ! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 
  |-
 
  |-
  | rowspan="3"| Statistic
+
  | rowspan="3" | ''protocol:''<br/><code>0x06</code><br/><br/>''resource:''<br/><code>resource_pack</code>
| Category ID
+
  | rowspan="3" | Configuration
  | rowspan="3"| Array
+
  | rowspan="3" | Server
  | VarInt
 
| See below.
 
 
  |-
 
  |-
  | Statistic ID
+
  | UUID
  | VarInt
+
  | {{Type|UUID}}
  | See below.
+
  | The unique identifier of the resource pack received in the [[#Add_Resource_Pack_(configuration)|Add Resource Pack (configuration)]] request.
 
  |-
 
  |-
  | Value
+
  | Result
  | VarInt
+
  | {{Type|VarInt}} {{Type|Enum}}
  | The amount to set it to.
+
  | Result ID (see below).
 
  |}
 
  |}
  
Categories (these are namespaced, but with <code>:</code> replaced with <code>.</code>):
+
Result can be one of the following values:
  
 
{| class="wikitable"
 
{| class="wikitable"
! Name
 
 
  ! ID
 
  ! ID
  ! Registry
+
  ! Result
 
  |-
 
  |-
| <code>minecraft.mined</code>
 
 
  | 0
 
  | 0
  | Blocks
+
  | Successfully downloaded
 
  |-
 
  |-
| <code>minecraft.crafted</code>
 
 
  | 1
 
  | 1
  | Items
+
  | Declined
 
  |-
 
  |-
| <code>minecraft.used</code>
 
 
  | 2
 
  | 2
  | Items
+
  | Failed to download
 
  |-
 
  |-
| <code>minecraft.broken</code>
 
 
  | 3
 
  | 3
  | Items
+
  | Accepted
 
  |-
 
  |-
| <code>minecraft.picked_up</code>
 
 
  | 4
 
  | 4
  | Items
+
  | Downloaded
 
  |-
 
  |-
| <code>minecraft.dropped</code>
 
 
  | 5
 
  | 5
  | Items
+
  | Invalid URL
 
  |-
 
  |-
| <code>minecraft.killed</code>
 
 
  | 6
 
  | 6
  | Entities
+
  | Failed to reload
 
  |-
 
  |-
| <code>minecraft.killed_by</code>
 
 
  | 7
 
  | 7
  | Entities
+
  | Discarded
|-
 
| <code>minecraft.custom</code>
 
| 8
 
| Custom
 
 
  |}
 
  |}
  
Blocks, Items, and Entities use block (not block state), item, and entity ids.
+
==== Serverbound Known Packs ====
 +
 
 +
Informs the server of which data packs are present on the client. The client sends this in response to [[#Clientbound_Known_Packs|Clientbound Known Packs]].
  
Custom has the following (unit only matters for clients):
+
If the client specifies a pack in this packet, the server should omit its contained data from the [[#Registry_Data|Registry Data]] packet.
  
 
{| class="wikitable"
 
{| class="wikitable"
  ! Name
+
  ! Packet ID
  ! ID
+
! State
  ! Unit
+
! Bound To
 +
! colspan="2"| Field Name
 +
  ! colspan="2"| Field Type
 +
  ! Notes
 
  |-
 
  |-
  | <code>minecraft.leave_game</code>
+
  | rowspan="4"| ''protocol:''<br/><code>0x07</code><br/><br/>''resource:''<br/><code>select_known_packs</code>
  | 0
+
  | rowspan="4"| Configuration
  | None
+
| rowspan="4"| Server
 +
| colspan="2"| Known Pack Count
 +
  | colspan="2"| {{Type|VarInt}}
 +
| The number of known packs in the following array.
 
  |-
 
  |-
  | <code>minecraft.play_one_minute</code>
+
  | rowspan="3"| Known Packs
  | 1
+
| Namespace
  | Time
+
| rowspan="3"| {{Type|Array}}
 +
  | {{Type|String}}
 +
  |
 
  |-
 
  |-
  | <code>minecraft.time_since_death</code>
+
  | ID
  | 2
+
  | {{Type|String}}
  | Time
+
  |
 
  |-
 
  |-
  | <code>minecraft.time_since_rest</code>
+
  | Version
  | 3
+
| {{Type|String}}
  | Time
+
  |
 +
  |}
 +
 
 +
== Play ==
 +
 
 +
=== Clientbound ===
 +
 
 +
==== Bundle Delimiter ====
 +
 
 +
The delimiter for a bundle of packets. When received, the client should store every subsequent packet it receives, and wait until another delimiter is received. Once that happens, the client is guaranteed to process every packet in the bundle on the same tick, and the client should stop storing packets.
 +
 
 +
As of 1.20.6, the Notchian server only uses this to ensure [[#Spawn_Entity|Spawn Entity]] and associated packets used to configure the entity happen on the same tick. Each entity gets a separate bundle.
 +
 
 +
The Notchian client doesn't allow more than 4096 packets in the same bundle.
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 
  |-
 
  |-
  | <code>minecraft.sneak_time</code>
+
  | ''protocol:''<br/><code>0x00</code><br/><br/>''resource:''<br/><code>bundle_delimiter</code>
  | 4
+
  | Play
  | Time
+
  | Client
  |-
+
  | colspan="3"| ''no fields''
  | <code>minecraft.walk_one_cm</code>
+
  |}
  | 5
+
 
  | Distance
+
==== Spawn Entity ====
 +
 
 +
Sent by the server when an entity (aside from [[#Spawn_Experience_Orb|Experience Orb]]) is created.
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
  ! Field Type
 +
  ! Notes
 
  |-
 
  |-
  | <code>minecraft.crouch_one_cm</code>
+
  | rowspan="13"| ''protocol:''<br/><code>0x01</code><br/><br/>''resource:''<br/><code>add_entity</code>
  | 6
+
  | rowspan="13"| Play
  | Distance
+
  | rowspan="13"| Client
 +
| Entity ID
 +
| {{Type|VarInt}}
 +
| A unique integer ID mostly used in the protocol to identify the entity.
 
  |-
 
  |-
  | <code>minecraft.sprint_one_cm</code>
+
  | Entity UUID
  | 7
+
  | {{Type|UUID}}
  | Distance
+
  | A unique identifier that is mostly used in persistence and places where the uniqueness matters more.
 
  |-
 
  |-
  | <code>minecraft.walk_on_water_one_cm</code>
+
  | Type
| 8
+
| {{Type|VarInt}}
| Distance
+
| ID in the <code>minecraft:entity_type</code> registry (see "type" field in [[Entity metadata#Entities]]).
 
  |-
 
  |-
  | <code>minecraft.fall_one_cm</code>
+
  | X
  | 9
+
  | {{Type|Double}}
  | Distance
+
  |
 
  |-
 
  |-
  | <code>minecraft.climb_one_cm</code>
+
  | Y
  | 10
+
  | {{Type|Double}}
  | Distance
+
  |
 
  |-
 
  |-
  | <code>minecraft.fly_one_cm</code>
+
  | Z
  | 11
+
  | {{Type|Double}}
  | Distance
+
  |
 
  |-
 
  |-
  | <code>minecraft.walk_under_water_one_cm</code>
+
  | Pitch
  | 12
+
  | {{Type|Angle}}
  | Distance
+
  | To get the real pitch, you must divide this by (256.0F / 360.0F)
 
  |-
 
  |-
  | <code>minecraft.minecart_one_cm</code>
+
  | Yaw
  | 13
+
  | {{Type|Angle}}
  | Distance
+
  | To get the real yaw, you must divide this by (256.0F / 360.0F)
 
  |-
 
  |-
  | <code>minecraft.boat_one_cm</code>
+
  | Head Yaw
  | 14
+
  | {{Type|Angle}}
  | Distance
+
  | Only used by living entities, where the head of the entity may differ from the general body rotation.
 
  |-
 
  |-
  | <code>minecraft.pig_one_cm</code>
+
  | Data
  | 15
+
  | {{Type|VarInt}}
  | Distance
+
  | Meaning dependent on the value of the Type field, see [[Object Data]] for details.
 
  |-
 
  |-
  | <code>minecraft.horse_one_cm</code>
+
  | Velocity X
  | 16
+
  | {{Type|Short}}
  | Distance
+
  | rowspan="3"| Same units as [[#Set Entity Velocity|Set Entity Velocity]].
 
  |-
 
  |-
  | <code>minecraft.aviate_one_cm</code>
+
  | Velocity Y
  | 17
+
  | {{Type|Short}}
| Distance
 
 
  |-
 
  |-
  | <code>minecraft.swim_one_cm</code>
+
  | Velocity Z
  | 18
+
| {{Type|Short}}
  | Distance
+
|}
 +
 
 +
{{Warning2|The points listed below should be considered when this packet is used to spawn a player entity.}}
 +
When in {{Minecraft Wiki|Server.properties#online-mode|online mode}}, the UUIDs must be valid and have valid skin blobs.
 +
In offline mode, the Notchian server uses [[Wikipedia:Universally unique identifier#Versions 3 and 5 (namespace name-based)|UUID v3]] and chooses the player's UUID by using the String <code>OfflinePlayer:&lt;player name&gt;</code>, encoding it in UTF-8 (and case-sensitive), then processes it with <code>[https://github.com/AdoptOpenJDK/openjdk-jdk8u/blob/9a91972c76ddda5c1ce28b50ca38cbd8a30b7a72/jdk/src/share/classes/java/util/UUID.java#L153-L175 UUID.nameUUIDFromBytes]</code>.
 +
 
 +
For NPCs UUID v2 should be used. Note:
 +
 
 +
  <+Grum> i will never confirm this as a feature you know that :)
 +
 
 +
In an example UUID, <code>xxxxxxxx-xxxx-Yxxx-xxxx-xxxxxxxxxxxx</code>, the UUID version is specified by <code>Y</code>. So, for UUID v3, <code>Y</code> will always be <code>3</code>, and for UUID v2, <code>Y</code> will always be <code>2</code>.
 +
 
 +
==== Spawn Experience Orb ====
 +
 
 +
Spawns one or more experience orbs.
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
  ! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 
  |-
 
  |-
  | <code>minecraft.strider_one_cm</code>
+
  | rowspan="5"| ''protocol:''<br/><code>0x02</code><br/><br/>''resource:''<br/><code>add_experience_orb</code>
  | 19
+
  | rowspan="5"| Play
  | Distance
+
| rowspan="5"| Client
 +
| Entity ID
 +
| {{Type|VarInt}}
 +
  |
 
  |-
 
  |-
  | <code>minecraft.jump</code>
+
  | X
  | 20
+
  | {{Type|Double}}
  | None
+
  |
 
  |-
 
  |-
  | <code>minecraft.drop</code>
+
  | Y
  | 21
+
  | {{Type|Double}}
  | None
+
  |
 
  |-
 
  |-
  | <code>minecraft.damage_dealt</code>
+
  | Z
  | 22
+
  | {{Type|Double}}
  | Damage
+
  |
 
  |-
 
  |-
  | <code>minecraft.damage_dealt_absorbed</code>
+
  | Count
  | 23
+
| {{Type|Short}}
  | Damage
+
| The amount of experience this orb will reward once collected.
 +
  |}
 +
 
 +
==== Entity Animation ====
 +
 
 +
Sent whenever an entity should change animation.
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
  ! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 
  |-
 
  |-
  | <code>minecraft.damage_dealt_resisted</code>
+
  | rowspan="2"| ''protocol:''<br/><code>0x03</code><br/><br/>''resource:''<br/><code>animate</code>
  | 24
+
  | rowspan="2"| Play
  | Damage
+
  | rowspan="2"| Client
 +
| Entity ID
 +
| {{Type|VarInt}}
 +
| Player ID.
 
  |-
 
  |-
  | <code>minecraft.damage_taken</code>
+
  | Animation
  | 25
+
| {{Type|Unsigned Byte}}
  | Damage
+
| Animation ID (see below).
 +
  |}
 +
 
 +
Animation can be one of the following values:
 +
 
 +
{| class="wikitable"
 +
  ! ID
 +
! Animation
 
  |-
 
  |-
  | <code>minecraft.damage_blocked_by_shield</code>
+
  | 0
  | 26
+
  | Swing main arm
| Damage
 
 
  |-
 
  |-
  | <code>minecraft.damage_absorbed</code>
+
  | 2
  | 27
+
  | Leave bed
| Damage
 
 
  |-
 
  |-
  | <code>minecraft.damage_resisted</code>
+
  | 3
  | 28
+
  | Swing offhand
| Damage
 
 
  |-
 
  |-
  | <code>minecraft.deaths</code>
+
  | 4
  | 29
+
  | Critical effect
| None
 
 
  |-
 
  |-
  | <code>minecraft.mob_kills</code>
+
  | 5
  | 30
+
| Magic critical effect
  | None
+
|}
 +
 
 +
==== Award Statistics ====
 +
 
 +
Sent as a response to [[#Client Status|Client Status]] (id 1). Will only send the changed values if previously requested.
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
  ! State
 +
! Bound To
 +
! colspan="2"| Field Name
 +
  ! colspan="2"| Field Type
 +
! Notes
 
  |-
 
  |-
  | <code>minecraft.animals_bred</code>
+
  | rowspan="4"| ''protocol:''<br/><code>0x04</code><br/><br/>''resource:''<br/><code>award_stats</code>
  | 31
+
  | rowspan="4"| Play
  | None
+
| rowspan="4"| Client
 +
| colspan="2"| Count
 +
  | colspan="2"| {{Type|VarInt}}
 +
| Number of elements in the following array.
 
  |-
 
  |-
  | <code>minecraft.player_kills</code>
+
  | rowspan="3"| Statistic
  | 32
+
| Category ID
  | None
+
| rowspan="3"| {{Type|Array}}
 +
  | {{Type|VarInt}}
 +
  | See below.
 
  |-
 
  |-
  | <code>minecraft.fish_caught</code>
+
  | Statistic ID
  | 33
+
  | {{Type|VarInt}}
  | None
+
  | See below.
 
  |-
 
  |-
  | <code>minecraft.talked_to_villager</code>
+
  | Value
  | 34
+
| {{Type|VarInt}}
  | None
+
| The amount to set it to.
 +
|}
 +
 
 +
Categories (these are namespaced, but with <code>:</code> replaced with <code>.</code>):
 +
 
 +
{| class="wikitable"
 +
! Name
 +
  ! ID
 +
  ! Registry
 
  |-
 
  |-
  | <code>minecraft.traded_with_villager</code>
+
  | <code>minecraft.mined</code>
  | 35
+
  | 0
  | None
+
  | Blocks
 
  |-
 
  |-
  | <code>minecraft.eat_cake_slice</code>
+
  | <code>minecraft.crafted</code>
  | 36
+
  | 1
  | None
+
  | Items
 
  |-
 
  |-
  | <code>minecraft.fill_cauldron</code>
+
  | <code>minecraft.used</code>
  | 37
+
  | 2
  | None
+
  | Items
 
  |-
 
  |-
  | <code>minecraft.use_cauldron</code>
+
  | <code>minecraft.broken</code>
  | 38
+
  | 3
  | None
+
  | Items
 
  |-
 
  |-
  | <code>minecraft.clean_armor</code>
+
  | <code>minecraft.picked_up</code>
  | 39
+
  | 4
  | None
+
  | Items
 
  |-
 
  |-
  | <code>minecraft.clean_banner</code>
+
  | <code>minecraft.dropped</code>
  | 40
+
  | 5
  | None
+
  | Items
 
  |-
 
  |-
  | <code>minecraft.clean_shulker_box</code>
+
  | <code>minecraft.killed</code>
  | 41
+
  | 6
  | None
+
  | Entities
 
  |-
 
  |-
  | <code>minecraft.interact_with_brewingstand</code>
+
  | <code>minecraft.killed_by</code>
  | 42
+
  | 7
  | None
+
  | Entities
 
  |-
 
  |-
  | <code>minecraft.interact_with_beacon</code>
+
  | <code>minecraft.custom</code>
  | 43
+
  | 8
  | None
+
  | Custom
  |-
+
  |}
  | <code>minecraft.inspect_dropper</code>
+
 
  | 44
+
Blocks, Items, and Entities use block (not block state), item, and entity ids.
  | None
+
 
 +
Custom has the following (unit only matters for clients):
 +
 
 +
{| class="wikitable"
 +
  ! Name
 +
  ! ID
 +
  ! Unit
 
  |-
 
  |-
  | <code>minecraft.inspect_hopper</code>
+
  | <code>minecraft.leave_game</code>
  | 45
+
  | 0
 
  | None
 
  | None
 
  |-
 
  |-
  | <code>minecraft.inspect_dispenser</code>
+
  | <code>minecraft.play_one_minute</code>
  | 46
+
  | 1
  | None
+
  | Time
 
  |-
 
  |-
  | <code>minecraft.play_noteblock</code>
+
  | <code>minecraft.time_since_death</code>
  | 47
+
  | 2
  | None
+
  | Time
 
  |-
 
  |-
  | <code>minecraft.tune_noteblock</code>
+
  | <code>minecraft.time_since_rest</code>
  | 48
+
  | 3
  | None
+
  | Time
 
  |-
 
  |-
  | <code>minecraft.pot_flower</code>
+
  | <code>minecraft.sneak_time</code>
  | 49
+
  | 4
  | None
+
  | Time
 
  |-
 
  |-
  | <code>minecraft.trigger_trapped_chest</code>
+
  | <code>minecraft.walk_one_cm</code>
  | 50
+
  | 5
  | None
+
  | Distance
 
  |-
 
  |-
  | <code>minecraft.open_enderchest</code>
+
  | <code>minecraft.crouch_one_cm</code>
  | 51
+
  | 6
  | None
+
  | Distance
 
  |-
 
  |-
  | <code>minecraft.enchant_item</code>
+
  | <code>minecraft.sprint_one_cm</code>
  | 52
+
  | 7
  | None
+
  | Distance
 
  |-
 
  |-
  | <code>minecraft.play_record</code>
+
  | <code>minecraft.walk_on_water_one_cm</code>
  | 53
+
  | 8
  | None
+
  | Distance
 
  |-
 
  |-
  | <code>minecraft.interact_with_furnace</code>
+
  | <code>minecraft.fall_one_cm</code>
  | 54
+
  | 9
  | None
+
  | Distance
 
  |-
 
  |-
  | <code>minecraft.interact_with_crafting_table</code>
+
  | <code>minecraft.climb_one_cm</code>
  | 55
+
  | 10
  | None
+
  | Distance
 
  |-
 
  |-
  | <code>minecraft.open_chest</code>
+
  | <code>minecraft.fly_one_cm</code>
  | 56
+
  | 11
  | None
+
  | Distance
 
  |-
 
  |-
  | <code>minecraft.sleep_in_bed</code>
+
  | <code>minecraft.walk_under_water_one_cm</code>
  | 57
+
  | 12
  | None
+
  | Distance
 
  |-
 
  |-
  | <code>minecraft.open_shulker_box</code>
+
  | <code>minecraft.minecart_one_cm</code>
  | 58
+
  | 13
  | None
+
  | Distance
 
  |-
 
  |-
  | <code>minecraft.open_barrel</code>
+
  | <code>minecraft.boat_one_cm</code>
  | 59
+
  | 14
  | None
+
  | Distance
 
  |-
 
  |-
  | <code>minecraft.interact_with_blast_furnace</code>
+
  | <code>minecraft.pig_one_cm</code>
  | 60
+
  | 15
  | None
+
  | Distance
 
  |-
 
  |-
  | <code>minecraft.interact_with_smoker</code>
+
  | <code>minecraft.horse_one_cm</code>
  | 61
+
  | 16
  | None
+
  | Distance
 
  |-
 
  |-
  | <code>minecraft.interact_with_lectern</code>
+
  | <code>minecraft.aviate_one_cm</code>
  | 62
+
  | 17
  | None
+
  | Distance
 
  |-
 
  |-
  | <code>minecraft.interact_with_campfire</code>
+
  | <code>minecraft.swim_one_cm</code>
  | 63
+
  | 18
  | None
+
  | Distance
 
  |-
 
  |-
  | <code>minecraft.interact_with_cartography_table</code>
+
  | <code>minecraft.strider_one_cm</code>
  | 64
+
  | 19
  | None
+
  | Distance
 
  |-
 
  |-
  | <code>minecraft.interact_with_loom</code>
+
  | <code>minecraft.jump</code>
  | 65
+
  | 20
 
  | None
 
  | None
 
  |-
 
  |-
  | <code>minecraft.interact_with_stonecutter</code>
+
  | <code>minecraft.drop</code>
  | 66
+
  | 21
 
  | None
 
  | None
 
  |-
 
  |-
  | <code>minecraft.bell_ring</code>
+
  | <code>minecraft.damage_dealt</code>
  | 67
+
  | 22
  | None
+
  | Damage
 
  |-
 
  |-
  | <code>minecraft.raid_trigger</code>
+
  | <code>minecraft.damage_dealt_absorbed</code>
  | 68
+
  | 23
  | None
+
  | Damage
 
  |-
 
  |-
  | <code>minecraft.raid_win</code>
+
  | <code>minecraft.damage_dealt_resisted</code>
  | 69
+
  | 24
  | None
+
  | Damage
 
  |-
 
  |-
  | <code>minecraft.interact_with_anvil</code>
+
  | <code>minecraft.damage_taken</code>
  | 70
+
  | 25
  | None
+
  | Damage
 
  |-
 
  |-
  | <code>minecraft.interact_with_grindstone</code>
+
  | <code>minecraft.damage_blocked_by_shield</code>
  | 71
+
  | 26
  | None
+
  | Damage
 
  |-
 
  |-
  | <code>minecraft.target_hit</code>
+
  | <code>minecraft.damage_absorbed</code>
  | 72
+
  | 27
  | None
+
  | Damage
 
  |-
 
  |-
  | <code>minecraft.interact_with_smithing_table</code>
+
  | <code>minecraft.damage_resisted</code>
  | 73
+
  | 28
 +
| Damage
 +
|-
 +
| <code>minecraft.deaths</code>
 +
| 29
 
  | None
 
  | None
|}
 
 
Units:
 
 
* None: just a normal number (formatted with 0 decimal places)
 
* Damage: value is 10 times the normal amount
 
* Distance: a distance in centimeters (hundredths of blocks)
 
* Time: a time span in ticks
 
 
==== Acknowledge Block Change ====
 
 
Acknowledges a user-initiated block change. After receiving this packet, the client will display the block state sent by the server instead of the one predicted by the client.
 
 
{| class="wikitable"
 
! Packet ID
 
! State
 
! Bound To
 
! Field Name
 
! Field Type
 
! Notes
 
 
  |-
 
  |-
  | rowspan="1"| 0x05
+
  | <code>minecraft.mob_kills</code>
| rowspan="1"| Play
+
  | 30
| rowspan="1"| Client
+
  | None
| Sequence ID
 
| VarInt
 
| Represents the sequence to acknowledge, this is used for properly syncing block changes to the client after interactions.
 
  |}
 
 
 
==== Set Block Destroy Stage ====
 
 
 
0–9 are the displayable destroy stages and each other number means that there is no animation on this coordinate.
 
 
 
Block break animations can still be applied on air; the animation will remain visible although there is no block being broken.  However, if this is applied to a transparent block, odd graphical effects may happen, including water losing its transparency. (An effect similar to this can be seen in normal gameplay when breaking ice blocks)
 
 
 
If you need to display several break animations at the same time you have to give each of them a unique Entity ID. The entity ID does not need to correspond to an actual entity on the client. It is valid to use a randomly generated number.
 
 
 
{| class="wikitable"
 
! Packet ID
 
! State
 
! Bound To
 
! Field Name
 
! Field Type
 
! Notes
 
 
  |-
 
  |-
  | rowspan="3"| 0x06
+
  | <code>minecraft.animals_bred</code>
| rowspan="3"| Play
+
  | 31
| rowspan="3"| Client
+
  | None
  | Entity ID
 
  | VarInt
 
| The ID of the entity breaking the block.
 
 
  |-
 
  |-
  | Location
+
  | <code>minecraft.player_kills</code>
  | Position
+
| 32
  | Block Position.
+
| None
 +
|-
 +
| <code>minecraft.fish_caught</code>
 +
| 33
 +
  | None
 +
  |-
 +
| <code>minecraft.talked_to_villager</code>
 +
| 34
 +
| None
 
  |-
 
  |-
  | Destroy Stage
+
  | <code>minecraft.traded_with_villager</code>
  | Byte
+
  | 35
  | 0–9 to set it, any other value to remove it.
+
  | None
|}
 
 
 
==== Block Entity Data ====
 
 
 
Sets the block entity associated with the block at the given location.
 
 
 
{| class="wikitable"
 
! Packet ID
 
! State
 
! Bound To
 
! Field Name
 
! Field Type
 
! Notes
 
 
  |-
 
  |-
  | rowspan="3"| 0x07
+
  | <code>minecraft.eat_cake_slice</code>
| rowspan="3"| Play
+
  | 36
| rowspan="3"| Client
+
  | None
| Location
 
  | Position
 
  |
 
 
  |-
 
  |-
  | Type
+
  | <code>minecraft.fill_cauldron</code>
  | VarInt
+
  | 37
  | The type of the block entity
+
  | None
 
  |-
 
  |-
  | NBT Data
+
  | <code>minecraft.use_cauldron</code>
| [[NBT|NBT Tag]]
+
| 38
| Data to set.  May be a TAG_END (0), in which case the block entity at the given location is removed (though this is not required since the client will remove the block entity automatically on chunk unload or block removal).
+
  | None
|}
 
 
 
==== Block Action ====
 
 
 
This packet is used for a number of actions and animations performed by blocks, usually non-persistent.  The client ignores the provided block type and instead uses the block state in their world.
 
 
 
See [[Block Actions]] for a list of values.
 
 
 
{{Warning2|This packet uses a block ID from the <code>minecraft:block</code> registry, not a block state.}}
 
 
 
{| class="wikitable"
 
  ! Packet ID
 
! State
 
! Bound To
 
! Field Name
 
! Field Type
 
! Notes
 
 
  |-
 
  |-
  | rowspan="4"| 0x08
+
  | <code>minecraft.clean_armor</code>
| rowspan="4"| Play
+
  | 39
| rowspan="4"| Client
+
  | None
  | Location
 
  | Position
 
| Block coordinates.
 
 
  |-
 
  |-
  | Action ID (Byte 1)
+
  | <code>minecraft.clean_banner</code>
  | Unsigned Byte
+
  | 40
  | Varies depending on block — see [[Block Actions]].
+
  | None
 
  |-
 
  |-
  | Action Parameter (Byte 2)
+
  | <code>minecraft.clean_shulker_box</code>
  | Unsigned Byte
+
  | 41
  | Varies depending on block — see [[Block Actions]].
+
  | None
 
  |-
 
  |-
  | Block Type
+
  | <code>minecraft.interact_with_brewingstand</code>
| VarInt
+
  | 42
| The block type ID for the block. This value is unused by the Notchian client, as it will infer the type of block based on the given position.
+
  | None
  |}
 
 
 
==== Block Update ====
 
 
 
Fired whenever a block is changed within the render distance.
 
 
 
{{Warning2|Changing a block in a chunk that is not loaded is not a stable action. The Notchian client currently uses a ''shared'' empty chunk which is modified for all block changes in unloaded chunks; while in 1.9 this chunk never renders in older versions the changed block will appear in all copies of the empty chunk.  Servers should avoid sending block changes in unloaded chunks and clients should ignore such packets.}}
 
 
 
{| class="wikitable"
 
! Packet ID
 
! State
 
! Bound To
 
! Field Name
 
! Field Type
 
! Notes
 
 
  |-
 
  |-
  | rowspan="2"| 0x09
+
  | <code>minecraft.interact_with_beacon</code>
| rowspan="2"| Play
+
  | 43
| rowspan="2"| Client
+
  | None
  | Location
 
  | Position
 
| Block Coordinates.
 
 
  |-
 
  |-
  | Block ID
+
  | <code>minecraft.inspect_dropper</code>
| VarInt
+
  | 44
| The new block state ID for the block as given in the [[Chunk Format#Block state registry|block state registry]].
+
  | None
  |}
 
 
 
==== Boss Bar ====
 
 
 
{| class="wikitable"
 
! Packet ID
 
! State
 
  ! Bound To
 
! colspan="2"| Field Name
 
! Field Type
 
! Notes
 
 
  |-
 
  |-
  | rowspan="14"| 0x0A
+
  | <code>minecraft.inspect_hopper</code>
| rowspan="14"| Play
+
  | 45
  | rowspan="14"| Client
+
  | None
  | colspan="2"| UUID
 
| UUID
 
| Unique ID for this bar.
 
 
  |-
 
  |-
  | colspan="2"| Action
+
  | <code>minecraft.inspect_dispenser</code>
  | VarInt Enum
+
  | 46
  | Determines the layout of the remaining packet.
+
  | None
 
  |-
 
  |-
  ! Action
+
  | <code>minecraft.play_noteblock</code>
  ! Field Name
+
  | 47
  !
+
  | None
!
 
 
  |-
 
  |-
  | rowspan="5"| 0: add
+
  | <code>minecraft.tune_noteblock</code>
| Title
+
  | 48
  | [[Chat]]
+
  | None
  |
 
 
  |-
 
  |-
  | Health
+
  | <code>minecraft.pot_flower</code>
  | Float
+
  | 49
  | From 0 to 1. Values greater than 1 do not crash a Notchian client, and start [https://i.johni0702.de/nA.png rendering part of a second health bar] at around 1.5.
+
  | None
 
  |-
 
  |-
  | Color
+
  | <code>minecraft.trigger_trapped_chest</code>
  | VarInt Enum
+
  | 50
  | Color ID (see below).
+
  | None
 
  |-
 
  |-
  | Division
+
  | <code>minecraft.open_enderchest</code>
  | VarInt Enum
+
  | 51
  | Type of division (see below).
+
  | None
 
  |-
 
  |-
  | Flags
+
  | <code>minecraft.enchant_item</code>
  | Unsigned Byte
+
  | 52
  | Bit mask. 0x1: should darken sky, 0x2: is dragon bar (used to play end music), 0x04: create fog (previously was also controlled by 0x02).
+
  | None
 
  |-
 
  |-
  | 1: remove
+
  | <code>minecraft.play_record</code>
  | ''no fields''
+
  | 53
  | ''no fields''
+
  | None
| Removes this boss bar.
 
 
  |-
 
  |-
  | 2: update health
+
  | <code>minecraft.interact_with_furnace</code>
  | Health
+
  | 54
  | Float
+
  | None
| ''as above''
 
 
  |-
 
  |-
  | 3: update title
+
  | <code>minecraft.interact_with_crafting_table</code>
  | Title
+
  | 55
| [[Chat]]
+
  | None
  |
 
 
  |-
 
  |-
  | rowspan="2"| 4: update style
+
  | <code>minecraft.open_chest</code>
| Color
+
  | 56
  | VarInt Enum
+
  | None
  | Color ID (see below).
 
 
  |-
 
  |-
  | Dividers
+
  | <code>minecraft.sleep_in_bed</code>
  | VarInt Enum
+
  | 57
  | ''as above''
+
  | None
 
  |-
 
  |-
  | 5: update flags
+
  | <code>minecraft.open_shulker_box</code>
  | Flags
+
  | 58
  | Unsigned Byte
+
  | None
| ''as above''
 
|}
 
 
 
{| class="wikitable"
 
! ID
 
! Color
 
 
  |-
 
  |-
  | 0
+
  | <code>minecraft.open_barrel</code>
  | Pink
+
  | 59
 +
| None
 
  |-
 
  |-
  | 1
+
  | <code>minecraft.interact_with_blast_furnace</code>
  | Blue
+
  | 60
 +
| None
 
  |-
 
  |-
  | 2
+
  | <code>minecraft.interact_with_smoker</code>
  | Red
+
  | 61
 +
| None
 +
|-
 +
| <code>minecraft.interact_with_lectern</code>
 +
| 62
 +
| None
 
  |-
 
  |-
  | 3
+
  | <code>minecraft.interact_with_campfire</code>
  | Green
+
  | 63
 +
| None
 
  |-
 
  |-
  | 4
+
  | <code>minecraft.interact_with_cartography_table</code>
  | Yellow
+
  | 64
 +
| None
 
  |-
 
  |-
  | 5
+
  | <code>minecraft.interact_with_loom</code>
  | Purple
+
  | 65
 +
| None
 
  |-
 
  |-
  | 6
+
  | <code>minecraft.interact_with_stonecutter</code>
  | White
+
  | 66
  |}
+
  | None
 
 
{| class="wikitable"
 
! ID
 
! Type of division
 
 
  |-
 
  |-
  | 0
+
  | <code>minecraft.bell_ring</code>
  | No division
+
  | 67
 +
| None
 
  |-
 
  |-
  | 1
+
  | <code>minecraft.raid_trigger</code>
  | 6 notches
+
  | 68
 +
| None
 
  |-
 
  |-
  | 2
+
  | <code>minecraft.raid_win</code>
  | 10 notches
+
  | 69
 +
| None
 
  |-
 
  |-
  | 3
+
  | <code>minecraft.interact_with_anvil</code>
  | 12 notches
+
  | 70
 +
| None
 
  |-
 
  |-
  | 4
+
  | <code>minecraft.interact_with_grindstone</code>
  | 20 notches
+
  | 71
  |}
+
  | None
 
 
==== Change Difficulty ====
 
 
 
Changes the difficulty setting in the client's option menu
 
 
 
{| class="wikitable"
 
! Packet ID
 
! State
 
! Bound To
 
! Field Name
 
! Field Type
 
! Notes
 
 
  |-
 
  |-
  | rowspan="2"| 0x0B
+
  | <code>minecraft.target_hit</code>
| rowspan="2"| Play
+
  | 72
| rowspan="2"| Client
+
  | None
  | Difficulty
 
  | Unsigned Byte
 
| 0: peaceful, 1: easy, 2: normal, 3: hard.
 
 
  |-
 
  |-
  | Difficulty locked?
+
  | <code>minecraft.interact_with_smithing_table</code>
  | Boolean
+
  | 73
  |
+
  | None
 
  |}
 
  |}
  
==== Chunk Batch Finished ====
+
Units:
  
{{Need Info|Why does the formula uses <code>25</code> instead of the normal tick duration of <code>50</code>?}}
+
* None: just a normal number (formatted with 0 decimal places)
 +
* Damage: value is 10 times the normal amount
 +
* Distance: a distance in centimeters (hundredths of blocks)
 +
* Time: a time span in ticks
  
Marks the end of a chunk batch. The Notchian client marks the time it receives this packet and calculates the ellapsed duration since the [[#Chunk Batch Start|beggining of the chunk batch]]. The server uses this duration and the batch size received in this packet to estimate the number of milliseconds ellapsed per chunk received. This value is then used to calculate the desired number of chunks per tick through the formula <code>25 / millisPerChunk</code>, which is reported to the server through [[#Chunk Batch Received|Chunk Batch Received]].
+
==== Acknowledge Block Change ====
  
The Notchian client uses the samples from the latest 15 batches to estimate the milliseconds per chunk number.
+
Acknowledges a user-initiated block change. After receiving this packet, the client will display the block state sent by the server instead of the one predicted by the client.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 1,854: Line 2,043:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="1"| 0x0C
+
  | rowspan="1"| ''protocol:''<br/><code>0x05</code><br/><br/>''resource:''<br/><code>block_change_ack</code>
 
  | rowspan="1"| Play
 
  | rowspan="1"| Play
 
  | rowspan="1"| Client
 
  | rowspan="1"| Client
  | Batch size
+
  | Sequence ID
  | VarInt
+
  | {{Type|VarInt}}
  | Number of chunks.
+
  | Represents the sequence to acknowledge, this is used for properly syncing block changes to the client after interactions.
 
  |}
 
  |}
  
==== Chunk Batch Start ====
+
==== Set Block Destroy Stage ====
 +
 
 +
0–9 are the displayable destroy stages and each other number means that there is no animation on this coordinate.
 +
 
 +
Block break animations can still be applied on air; the animation will remain visible although there is no block being broken.  However, if this is applied to a transparent block, odd graphical effects may happen, including water losing its transparency.  (An effect similar to this can be seen in normal gameplay when breaking ice blocks)
  
Marks the start of a chunk batch. The Notchian client marks and stores the time it receives this packet.
+
If you need to display several break animations at the same time you have to give each of them a unique Entity ID. The entity ID does not need to correspond to an actual entity on the client. It is valid to use a randomly generated number.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 1,874: Line 2,067:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | 0x0D
+
  | rowspan="3"| ''protocol:''<br/><code>0x06</code><br/><br/>''resource:''<br/><code>block_destruction</code>
| Play
+
  | rowspan="3"| Play
| Client
+
| rowspan="3"| Client
| colspan="3"| ''no fields''
+
  | Entity ID
  |}
+
  | {{Type|VarInt}}
 
+
  | The ID of the entity breaking the block.
==== Chunk Biomes ====
 
 
 
{| class="wikitable"
 
  ! Packet ID
 
  ! State
 
! Bound To
 
! colspan="2"| Field Name
 
  ! colspan="2"| Field Type
 
! Notes
 
 
  |-
 
  |-
  | rowspan="6"| 0x0E
+
  | Location
  | rowspan="6"| Play
+
  | {{Type|Position}}
  | rowspan="6"| Client
+
  | Block Position.
 
  |-
 
  |-
  | colspan="2"| Number of chunks
+
  | Destroy Stage
| colspan="2"| VarInt
+
  | {{Type|Byte}}
| Number of elements in the following array
+
  | 0–9 to set it, any other value to remove it.
|-
 
  | rowspan="4"| Chunk biome data
 
| Chunk X
 
| rowspan="4"| Array
 
| Int
 
| Chunk coordinate (block coordinate divided by 16, rounded down)
 
|-
 
| Chunk Z
 
| Int
 
| Chunk coordinate (block coordinate divided by 16, rounded down)
 
|-
 
| Size
 
| VarInt
 
| Size of Data in bytes
 
|-
 
| Data
 
| Byte array
 
  | Chunk [[Chunk Format#Data structure|data structure]], with [[Chunk Format#Chunk_Section|sections]] containing only the <code>Biomes</code> field
 
 
  |}
 
  |}
  
==== Clear Titles ====
+
==== Block Entity Data ====
  
Clear the client's current title information, with the option to also reset it.
+
Sets the block entity associated with the block at the given location.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 1,929: Line 2,095:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="1"| 0x0F
+
  | rowspan="3"| ''protocol:''<br/><code>0x07</code><br/><br/>''resource:''<br/><code>block_entity_data</code>
  | rowspan="1"| Play
+
  | rowspan="3"| Play
  | rowspan="1"| Client
+
  | rowspan="3"| Client
  | Reset
+
  | Location
  | Boolean
+
  | {{Type|Position}}
 
  |
 
  |
 +
|-
 +
| Type
 +
| {{Type|VarInt}}
 +
| The type of the block entity
 +
|-
 +
| NBT Data
 +
| {{Type|NBT}}
 +
| Data to set.  May be a TAG_END (0), in which case the block entity at the given location is removed (though this is not required since the client will remove the block entity automatically on chunk unload or block removal).
 
  |}
 
  |}
  
==== Command Suggestions Response ====
+
==== Block Action ====
 +
 
 +
This packet is used for a number of actions and animations performed by blocks, usually non-persistent.  The client ignores the provided block type and instead uses the block state in their world.
 +
 
 +
See [[Block Actions]] for a list of values.
  
The server responds with a list of auto-completions of the last word sent to it. In the case of regular chat, this is a player username. Command names and parameters are also supported. The client sorts these alphabetically before listing them.
+
{{Warning2|This packet uses a block ID from the <code>minecraft:block</code> registry, not a block state.}}
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 1,945: Line 2,123:
 
  ! State
 
  ! State
 
  ! Bound To
 
  ! Bound To
  ! colspan="2"| Field Name
+
  ! Field Name
  ! colspan="2"| Field Type
+
  ! Field Type
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="8"| 0x10
+
  | rowspan="4"| 0x08
  | rowspan="8"| Play
+
  | rowspan="4"| Play
  | rowspan="8"| Client
+
  | rowspan="4"| Client
 +
| Location
 +
| {{Type|Position}}
 +
| Block coordinates.
 
  |-
 
  |-
  | colspan="2"| ID
+
  | Action ID (Byte 1)
  | colspan="2"| VarInt
+
  | {{Type|Unsigned Byte}}
  | Transaction ID.
+
  | Varies depending on block — see [[Block Actions]].
 
  |-
 
  |-
  | colspan="2"| Start
+
  | Action Parameter (Byte 2)
  | colspan="2"| VarInt
+
  | {{Type|Unsigned Byte}}
  | Start of the text to replace.
+
  | Varies depending on block — see [[Block Actions]].
 
  |-
 
  |-
  | colspan="2"| Length
+
  | Block Type
  | colspan="2"| VarInt
+
  | {{Type|VarInt}}
  | Length of the text to replace.
+
  | The block type ID for the block. This value is unused by the Notchian client, as it will infer the type of block based on the given position.
|-
 
| colspan="2"| Count
 
| colspan="2"| VarInt
 
| Number of elements in the following array.
 
|-
 
| rowspan="3"| Matches
 
| Match
 
| rowspan="3"| Array
 
| String (32767)
 
| One eligible value to insert, note that each command is sent separately instead of in a single string, hence the need for Count.  Note that for instance this doesn't include a leading <code>/</code> on commands.
 
|-
 
| Has tooltip
 
| Boolean
 
| True if the following is present.
 
|-
 
| Tooltip
 
| Optional [[Chat]]
 
| Tooltip to display; only present if previous boolean is true.
 
 
  |}
 
  |}
  
==== Commands ====
+
==== Block Update ====
  
Lists all of the commands on the server, and how they are parsed.
+
Fired whenever a block is changed within the render distance.
  
This is a directed graph, with one root nodeEach redirect or child node must refer only to nodes that have already been declared.
+
{{Warning2|Changing a block in a chunk that is not loaded is not a stable action.  The Notchian client currently uses a ''shared'' empty chunk which is modified for all block changes in unloaded chunks; while in 1.9 this chunk never renders in older versions the changed block will appear in all copies of the empty chunkServers should avoid sending block changes in unloaded chunks and clients should ignore such packets.}}
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 1,998: Line 2,161:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="3"| 0x11
+
  | rowspan="2"| 0x09
  | rowspan="3"| Play
+
  | rowspan="2"| Play
  | rowspan="3"| Client
+
  | rowspan="2"| Client
  | Count
+
  | Location
  | VarInt
+
  | {{Type|Position}}
  | Number of elements in the following array.
+
  | Block Coordinates.
 
  |-
 
  |-
  | Nodes
+
  | Block ID
  | Array of [[Command Data|Node]]
+
  | {{Type|VarInt}}
| An array of nodes.
+
  | The new block state ID for the block as given in the [[Chunk Format#Block state registry|block state registry]].
|-
 
| Root index
 
| VarInt
 
  | Index of the <code>root</code> node in the previous array.
 
 
  |}
 
  |}
  
For more information on this packet, see the [[Command Data]] article.
+
==== Boss Bar ====
 
 
==== Close Container ====
 
 
 
This packet is sent from the server to the client when a window is forcibly closed, such as when a chest is destroyed while it's open. The notchian client disregards the provided window ID and closes any active window.
 
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 2,024: Line 2,179:
 
  ! State
 
  ! State
 
  ! Bound To
 
  ! Bound To
  ! Field Name
+
  ! colspan="2"| Field Name
 
  ! Field Type
 
  ! Field Type
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | 0x12
+
  | rowspan="14"| 0x0A
  | Play
+
  | rowspan="14"| Play
  | Client
+
  | rowspan="14"| Client
  | Window ID
+
  | colspan="2"| UUID
  | Unsigned Byte
+
  | {{Type|UUID}}
  | This is the ID of the window that was closed. 0 for inventory.
+
  | Unique ID for this bar.
  |}
+
  |-
 
+
| colspan="2"| Action
==== Set Container Content ====
+
| {{Type|VarInt}} {{Type|Enum}}
[[File:Inventory-slots.png|thumb|The inventory slots]]
+
| Determines the layout of the remaining packet.
 
+
|-
Sent by the server when items in multiple slots (in a window) are added/removed. This includes the main inventory, equipped armour and crafting slots. This packet with Window ID set to "0" is sent during the player joining sequence to initialise the player's inventory.
+
  ! Action
 
 
{| class="wikitable"
 
! Packet ID
 
! State
 
  ! Bound To
 
 
  ! Field Name
 
  ! Field Name
  ! Field Type
+
  !
  ! Notes
+
  !
 
  |-
 
  |-
  | rowspan="5"| 0x13
+
  | rowspan="5"| 0: add
  | rowspan="5"| Play
+
  | Title
  | rowspan="5"| Client
+
  | {{Type|Text Component}}
  | Window ID
+
  |
| Unsigned Byte
 
| The ID of window which items are being sent for. 0 for player inventory.
 
 
  |-
 
  |-
  | State ID
+
  | Health
  | VarInt
+
  | {{Type|Float}}
  | The last received State ID from either a [[#Set Container Slot|Set Container Slot]] or a [[#Set Container Content|Set Container Content]] packet
+
  | From 0 to 1. Values greater than 1 do not crash a Notchian client, and start [https://i.johni0702.de/nA.png rendering part of a second health bar] at around 1.5.
 
  |-
 
  |-
  | Count
+
  | Color
  | VarInt
+
  | {{Type|VarInt}} {{Type|Enum}}
  | Number of elements in the following array.
+
  | Color ID (see below).
 
  |-
 
  |-
  | Slot Data
+
  | Division
  | Array of [[Slot Data|Slot]]
+
  | {{Type|VarInt}} {{Type|Enum}}
 +
| Type of division (see below).
 
  |-
 
  |-
  | Carried Item
+
  | Flags
  | [[Slot Data|Slot]]
+
  | {{Type|Unsigned Byte}}
  | Item held by player.
+
  | Bit mask. 0x01: should darken sky, 0x02: is dragon bar (used to play end music), 0x04: create fog (previously was also controlled by 0x02).
  |}
+
  |-
 
+
| 1: remove
See [[Inventory#Windows|inventory windows]] for further information about how slots are indexed.
+
| ''no fields''
Use [[#Open Screen|Open Screen]] to open the container on the client.
+
| ''no fields''
 
+
  | Removes this boss bar.
==== Set Container Property ====
+
  |-
 
+
  | 2: update health
This packet is used to inform the client that part of a GUI window should be updated.
+
  | Health
 
+
  | {{Type|Float}}
{| class="wikitable"
+
  | ''as above''
  ! Packet ID
 
  ! State
 
  ! Bound To
 
  ! Field Name
 
  ! Field Type
 
  ! Notes
 
 
  |-
 
  |-
  | rowspan="3"| 0x14
+
  | 3: update title
| rowspan="3"| Play
+
  | Title
  | rowspan="3"| Client
+
  | {{Type|Text Component}}
  | Window ID
 
| Unsigned Byte
 
 
  |
 
  |
 
  |-
 
  |-
  | Property
+
  | rowspan="2"| 4: update style
  | Short
+
  | Color
  | The property to be updated, see below.
+
| {{Type|VarInt}} {{Type|Enum}}
 +
  | Color ID (see below).
 +
|-
 +
| Dividers
 +
| {{Type|VarInt}} {{Type|Enum}}
 +
| ''as above''
 
  |-
 
  |-
  | Value
+
  | 5: update flags
  | Short
+
  | Flags
  | The new value for the property, see below.
+
  | {{Type|Unsigned Byte}}
 +
| ''as above''
 
  |}
 
  |}
 
The meaning of the Property field depends on the type of the window. The following table shows the known combinations of window type and property, and how the value is to be interpreted.
 
  
 
{| class="wikitable"
 
{| class="wikitable"
 +
! ID
 +
! Color
 
  |-
 
  |-
  ! Window type
+
  | 0
  ! Property
+
  | Pink
! Value
 
 
  |-
 
  |-
  | rowspan="4"| Furnace
+
  | 1
| 0: Fire icon (fuel left)
+
  | Blue
  | counting from fuel burn time down to 0 (in-game ticks)
 
 
  |-
 
  |-
  | 1: Maximum fuel burn time
+
  | 2
  | fuel burn time or 0 (in-game ticks)
+
  | Red
 
  |-
 
  |-
  | 2: Progress arrow
+
  | 3
  | counting from 0 to maximum progress (in-game ticks)
+
  | Green
 
  |-
 
  |-
  | 3: Maximum progress
+
  | 4
  | always 200 on the notchian server
+
  | Yellow
 
  |-
 
  |-
  | rowspan="10"| Enchantment Table
+
  | 5
  | 0: Level requirement for top enchantment slot
+
  | Purple
| rowspan="3"| The enchantment's xp level requirement
 
 
  |-
 
  |-
  | 1: Level requirement for middle enchantment slot
+
  | 6
 +
| White
 +
|}
 +
 
 +
{| class="wikitable"
 +
! ID
 +
! Type of division
 
  |-
 
  |-
  | 2: Level requirement for bottom enchantment slot
+
  | 0
 +
| No division
 
  |-
 
  |-
  | 3: The enchantment seed
+
  | 1
  | Used for drawing the enchantment names (in [[Wikipedia:Standard Galactic Alphabet|SGA]]) clientside.  The same seed ''is'' used to calculate enchantments, but some of the data isn't sent to the client to prevent easily guessing the entire list (the seed value here is the regular seed bitwise and <code>0xFFFFFFF0</code>).
+
  | 6 notches
 
  |-
 
  |-
  | 4: Enchantment ID shown on mouse hover over top enchantment slot
+
  | 2
  | rowspan="3"| The enchantment id (set to -1 to hide it), see below for values
+
  | 10 notches
 
  |-
 
  |-
  | 5: Enchantment ID shown on mouse hover over middle enchantment slot
+
  | 3
 +
| 12 notches
 
  |-
 
  |-
  | 6: Enchantment ID shown on mouse hover over bottom enchantment slot
+
  | 4
  |-
+
  | 20 notches
  | 7: Enchantment level shown on mouse hover over the top slot
+
  |}
| rowspan="3"| The enchantment level (1 = I, 2 = II, 6 = VI, etc.), or -1 if no enchant
+
 
  |-
+
==== Change Difficulty ====
  | 8: Enchantment level shown on mouse hover over the middle slot
+
 
  |-
+
Changes the difficulty setting in the client's option menu
  | 9: Enchantment level shown on mouse hover over the bottom slot
+
 
 +
{| class="wikitable"
 +
  ! Packet ID
 +
! State
 +
! Bound To
 +
  ! Field Name
 +
  ! Field Type
 +
  ! Notes
 
  |-
 
  |-
  | rowspan="3"| Beacon
+
  | rowspan="2"| 0x0B
  | 0: Power level
+
| rowspan="2"| Play
  | 0-4, controls what effect buttons are enabled
+
| rowspan="2"| Client
 +
| Difficulty
 +
  | {{Type|Unsigned Byte}}
 +
  | 0: peaceful, 1: easy, 2: normal, 3: hard.
 
  |-
 
  |-
  | 1: First potion effect
+
  | Difficulty locked?
  | {{Minecraft Wiki|Data values#Status effects|Potion effect ID}} for the first effect, or -1 if no effect
+
  | {{Type|Boolean}}
|-
+
  |
| 2: Second potion effect
 
| {{Minecraft Wiki|Data values#Status effects|Potion effect ID}} for the second effect, or -1 if no effect
 
|-
 
| Anvil
 
| 0: Repair cost
 
| The repair's cost in xp levels
 
|-
 
| rowspan="2"| Brewing Stand
 
| 0: Brew time
 
| 0 – 400, with 400 making the arrow empty, and 0 making the arrow full
 
|-
 
| 1: Fuel time
 
| 0 - 20, with 0 making the arrow empty, and 20 making the arrow full
 
|-
 
| Stonecutter
 
| 0: Selected recipe
 
| The index of the selected recipe. -1 means none is selected.
 
|-
 
| Loom
 
| 0: Selected pattern
 
| The index of the selected pattern. 0 means none is selected, 0 is also the internal id of the "base" pattern.
 
|-
 
| Lectern
 
| 0: Page number
 
  | The current page number, starting from 0.
 
 
  |}
 
  |}
  
For an enchanting table, the following numerical IDs are used:
+
==== Chunk Batch Finished ====
 +
 
 +
Marks the end of a chunk batch. The Notchian client marks the time it receives this packet and calculates the elapsed duration since the [[#Chunk Batch Start|beginning of the chunk batch]]. The server uses this duration and the batch size received in this packet to estimate the number of milliseconds elapsed per chunk received. This value is then used to calculate the desired number of chunks per tick through the formula <code>25 / millisPerChunk</code>, which is reported to the server through [[#Chunk Batch Received|Chunk Batch Received]]. This likely uses <code>25</code> instead of the normal tick duration of <code>50</code> so chunk processing will only use half of the client's and network's bandwidth.
 +
 
 +
The Notchian client uses the samples from the latest 15 batches to estimate the milliseconds per chunk number.
  
 
{| class="wikitable"
 
{| class="wikitable"
  ! Numerical ID
+
  ! Packet ID
  ! Enchantment ID
+
  ! State
  ! Enchantment Name
+
! Bound To
 +
  ! Field Name
 +
! Field Type
 +
! Notes
 
  |-
 
  |-
  | 0
+
  | rowspan="1"| ''protocol:''<br/><code>0x0C</code><br/><br/>''resource:''<br/><code>chunk_batch_finished</code>
  | minecraft:protection
+
| rowspan="1"| Play
  | Protection
+
  | rowspan="1"| Client
 +
| Batch size
 +
| {{Type|VarInt}}
 +
| Number of chunks.
 +
  |}
 +
 
 +
==== Chunk Batch Start ====
 +
 
 +
Marks the start of a chunk batch. The Notchian client marks and stores the time it receives this packet.
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 
  |-
 
  |-
  | 1
+
  | ''protocol:''<br/><code>0x0D</code><br/><br/>''resource:''<br/><code>chunk_batch_start</code>
  | minecraft:fire_protection
+
| Play
  | Fire Protection
+
| Client
 +
  | colspan="3"| ''no fields''
 +
|}
 +
 
 +
==== Chunk Biomes ====
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! colspan="2"| Field Name
 +
  ! colspan="2"| Field Type
 +
! Notes
 
  |-
 
  |-
  | 2
+
  | rowspan="6"| 0x0E
  | minecraft:feather_falling
+
  | rowspan="6"| Play
  | Feather Falling
+
  | rowspan="6"| Client
 
  |-
 
  |-
  | 3
+
  | colspan="2"| Number of chunks
  | minecraft:blast_protection
+
  | colspan="2"| {{Type|VarInt}}
  | Blast Protection
+
  | Number of elements in the following array
 
  |-
 
  |-
  | 4
+
  | rowspan="4"| Chunk biome data
  | minecraft:projectile_protection
+
| Chunk Z
  | Projectile Protection
+
  | rowspan="4"| {{Type|Array}}
 +
| {{Type|Int}}
 +
  | Chunk coordinate (block coordinate divided by 16, rounded down)
 
  |-
 
  |-
  | 5
+
  | Chunk X
  | minecraft:respiration
+
  | {{Type|Int}}
  | Respiration
+
  | Chunk coordinate (block coordinate divided by 16, rounded down)
 
  |-
 
  |-
  | 6
+
  | Size
  | minecraft:aqua_affinity
+
  | {{Type|VarInt}}
  | Aqua Affinity
+
  | Size of Data in bytes
 
  |-
 
  |-
  | 7
+
  | Data
  | minecraft:thorns
+
  | {{Type|Byte Array}}
  | Thorns
+
| Chunk [[Chunk Format#Data structure|data structure]], with [[Chunk Format#Chunk_Section|sections]] containing only the <code>Biomes</code> field
 +
|}
 +
 
 +
Note: The order of X and Z is inverted, because the client reads them as one big-endian {{Type|Long}}, with Z being the upper 32 bits.
 +
 
 +
==== Clear Titles ====
 +
 
 +
Clear the client's current title information, with the option to also reset it.
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
  ! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 
  |-
 
  |-
  | 8
+
  | rowspan="1"| 0x0F
  | minecraft:depth_strider
+
| rowspan="1"| Play
  | Depth Strider
+
  | rowspan="1"| Client
 +
  | Reset
 +
| {{Type|Boolean}}
 +
|
 +
|}
 +
 
 +
==== Command Suggestions Response ====
 +
 
 +
The server responds with a list of auto-completions of the last word sent to it. In the case of regular chat, this is a player username. Command names and parameters are also supported. The client sorts these alphabetically before listing them.
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! colspan="2"| Field Name
 +
! colspan="2"| Field Type
 +
! Notes
 
  |-
 
  |-
  | 9
+
  | rowspan="8"| 0x10
  | minecraft:frost_walker
+
  | rowspan="8"| Play
  | Frost Walker
+
  | rowspan="8"| Client
 
  |-
 
  |-
  | 10
+
  | colspan="2"| ID
  | minecraft:binding_curse
+
  | colspan="2"| {{Type|VarInt}}
  | Curse of Binding
+
  | Transaction ID.
 
  |-
 
  |-
  | 11
+
  | colspan="2"| Start
  | minecraft:soul_speed
+
  | colspan="2"| {{Type|VarInt}}
  | Soul Speed
+
  | Start of the text to replace.
 
  |-
 
  |-
  | 12
+
  | colspan="2"| Length
  | minecraft:sharpness
+
  | colspan="2"| {{Type|VarInt}}
  | Sharpness
+
  | Length of the text to replace.
 
  |-
 
  |-
  | 13
+
  | colspan="2"| Count
  | minecraft:smite
+
  | colspan="2"| {{Type|VarInt}}
  | Smite
+
  | Number of elements in the following array.
 
  |-
 
  |-
  | 14
+
  | rowspan="3"| Matches
  | minecraft:bane_of_arthropods
+
| Match
  | Bane of Arthropods
+
  | rowspan="3"| {{Type|Array}}
 +
  | {{Type|String}} (32767)
 +
| One eligible value to insert, note that each command is sent separately instead of in a single string, hence the need for Count.  Note that for instance this doesn't include a leading <code>/</code> on commands.
 
  |-
 
  |-
  | 15
+
  | Has tooltip
  | minecraft:knockback
+
  | {{Type|Boolean}}
  | Knockback
+
  | True if the following is present.
 
  |-
 
  |-
  | 16
+
  | Tooltip
  | minecraft:fire_aspect
+
  | {{Type|Optional}} {{Type|Text Component}}
  | Fire Aspect
+
  | Tooltip to display; only present if previous boolean is true.
 +
|}
 +
 
 +
==== Commands ====
 +
 
 +
Lists all of the commands on the server, and how they are parsed.
 +
 
 +
This is a directed graph, with one root node.  Each redirect or child node must refer only to nodes that have already been declared.
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 
  |-
 
  |-
  | 17
+
  | rowspan="3"| 0x11
  | minecraft:looting
+
  | rowspan="3"| Play
  | Looting
+
| rowspan="3"| Client
 +
| Count
 +
| {{Type|VarInt}}
 +
  | Number of elements in the following array.
 
  |-
 
  |-
  | 18
+
  | Nodes
  | minecraft:sweeping
+
  | {{Type|Array}} of [[Command Data|Node]]
  | Sweeping Edge
+
  | An array of nodes.
 
  |-
 
  |-
  | 19
+
  | Root index
  | minecraft:efficiency
+
  | {{Type|VarInt}}
  | Efficiency
+
| Index of the <code>root</code> node in the previous array.
 +
  |}
 +
 
 +
For more information on this packet, see the [[Command Data]] article.
 +
 
 +
==== Close Container ====
 +
 
 +
This packet is sent from the server to the client when a window is forcibly closed, such as when a chest is destroyed while it's open. The notchian client disregards the provided window ID and closes any active window.
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 
  |-
 
  |-
  | 20
+
  | 0x12
  | minecraft:silk_touch
+
  | Play
  | Silk Touch
+
| Client
 +
| Window ID
 +
| {{Type|Unsigned Byte}}
 +
| This is the ID of the window that was closed. 0 for inventory.
 +
|}
 +
 
 +
==== Set Container Content ====
 +
[[File:Inventory-slots.png|thumb|The inventory slots]]
 +
 
 +
Replaces the contents of a container window. Sent by the server upon initialization of a container window or the player's inventory, and in response to state ID mismatches (see [[#Click Container]]).
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
  ! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 
  |-
 
  |-
  | 21
+
  | rowspan="5"| 0x13
  | minecraft:unbreaking
+
  | rowspan="5"| Play
  | Unbreaking
+
| rowspan="5"| Client
 +
| Window ID
 +
| {{Type|Unsigned Byte}}
 +
  | The ID of window which items are being sent for. 0 for player inventory. The client ignores any packets targeting a Window ID other than the current one. However, an exception is made for the player inventory, which may be targeted at any time. (The Notchian server does not appear to utilize this special case.)
 
  |-
 
  |-
  | 22
+
  | State ID
  | minecraft:fortune
+
  | {{Type|VarInt}}
  | Fortune
+
  | A server-managed sequence number used to avoid desynchronization; see [[#Click Container]].
 
  |-
 
  |-
  | 23
+
  | Count
  | minecraft:power
+
  | {{Type|VarInt}}
  | Power
+
  | Number of elements in the following array.
 
  |-
 
  |-
  | 24
+
  | Slot Data
  | minecraft:punch
+
  | {{Type|Array}} of [[Slot Data|Slot]]
| Punch
 
 
  |-
 
  |-
  | 25
+
  | Carried Item
  | minecraft:flame
+
  | {{Type|Slot}}
  | Flame
+
| Item being dragged with the mouse.
 +
  |}
 +
 
 +
See [[Inventory#Windows|inventory windows]] for further information about how slots are indexed.
 +
Use [[#Open Screen|Open Screen]] to open the container on the client.
 +
 
 +
==== Set Container Property ====
 +
 
 +
This packet is used to inform the client that part of a GUI window should be updated.
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 
  |-
 
  |-
  | 26
+
  | rowspan="3"| 0x14
  | minecraft:infinity
+
  | rowspan="3"| Play
  | Infinity
+
| rowspan="3"| Client
 +
| Window ID
 +
| {{Type|Unsigned Byte}}
 +
  |
 
  |-
 
  |-
  | 27
+
  | Property
  | minecraft:luck_of_the_sea
+
  | {{Type|Short}}
  | Luck of the Sea
+
  | The property to be updated, see below.
 
  |-
 
  |-
  | 28
+
  | Value
  | minecraft:lure
+
  | {{Type|Short}}
  | Lure
+
  | The new value for the property, see below.
 +
|}
 +
 
 +
The meaning of the Property field depends on the type of the window. The following table shows the known combinations of window type and property, and how the value is to be interpreted.
 +
 
 +
{| class="wikitable"
 
  |-
 
  |-
  | 29
+
  ! Window type
  | minecraft:loyalty
+
  ! Property
  | Loyalty
+
  ! Value
 
  |-
 
  |-
  | 30
+
  | rowspan="4"| Furnace
  | minecraft:impaling
+
  | 0: Fire icon (fuel left)
  | Impaling
+
  | counting from fuel burn time down to 0 (in-game ticks)
 
  |-
 
  |-
  | 31
+
  | 1: Maximum fuel burn time
| minecraft:riptide
+
  | fuel burn time or 0 (in-game ticks)
  | Riptide
 
 
  |-
 
  |-
  | 32
+
  | 2: Progress arrow
| minecraft:channeling
+
  | counting from 0 to maximum progress (in-game ticks)
  | Channeling
 
 
  |-
 
  |-
  | 33
+
  | 3: Maximum progress
| minecraft:multishot
+
  | always 200 on the notchian server
  | Multishot
 
 
  |-
 
  |-
  | 34
+
  | rowspan="10"| Enchantment Table
  | minecraft:quick_charge
+
  | 0: Level requirement for top enchantment slot
  | Quick Charge
+
  | rowspan="3"| The enchantment's xp level requirement
 
  |-
 
  |-
  | 35
+
  | 1: Level requirement for middle enchantment slot
| minecraft:piercing
 
| Piercing
 
 
  |-
 
  |-
  | 36
+
  | 2: Level requirement for bottom enchantment slot
| minecraft:mending
 
| Mending
 
 
  |-
 
  |-
  | 37
+
  | 3: The enchantment seed
  | minecraft:vanishing_curse
+
  | Used for drawing the enchantment names (in [[Wikipedia:Standard Galactic Alphabet|SGA]]) clientside. The same seed ''is'' used to calculate enchantments, but some of the data isn't sent to the client to prevent easily guessing the entire list (the seed value here is the regular seed bitwise and <code>0xFFFFFFF0</code>).
  | Curse of Vanishing
 
|}
 
 
 
==== Set Container Slot ====
 
 
 
Sent by the server when an item in a slot (in a window) is added/removed.
 
 
 
{| class="wikitable"
 
! Packet ID
 
! State
 
! Bound To
 
! Field Name
 
! Field Type
 
! Notes
 
 
  |-
 
  |-
  | rowspan="4"| 0x15
+
| 4: Enchantment ID shown on mouse hover over top enchantment slot
  | rowspan="4"| Play
+
  | rowspan="3"| The enchantment id (set to -1 to hide it), see below for values
  | rowspan="4"| Client
+
|-
  | Window ID
+
| 5: Enchantment ID shown on mouse hover over middle enchantment slot
  | Byte
+
|-
  | The window which is being updated. 0 for player inventory. Note that all known window types include the player inventory. This packet will only be sent for the currently opened window while the player is performing actions, even if it affects the player inventory. After the window is closed, a number of these packets are sent to update the player's inventory window (0).
+
| 6: Enchantment ID shown on mouse hover over bottom enchantment slot
 +
|-
 +
| 7: Enchantment level shown on mouse hover over the top slot
 +
  | rowspan="3"| The enchantment level (1 = I, 2 = II, 6 = VI, etc.), or -1 if no enchant
 +
|-
 +
| 8: Enchantment level shown on mouse hover over the middle slot
 +
|-
 +
| 9: Enchantment level shown on mouse hover over the bottom slot
 +
|-
 +
  | rowspan="3"| Beacon
 +
| 0: Power level
 +
| 0-4, controls what effect buttons are enabled
 +
  |-
 +
  | 1: First potion effect
 +
  | {{Minecraft Wiki|Data values#Status effects|Potion effect ID}} for the first effect, or -1 if no effect
 +
|-
 +
| 2: Second potion effect
 +
| {{Minecraft Wiki|Data values#Status effects|Potion effect ID}} for the second effect, or -1 if no effect
 +
|-
 +
| Anvil
 +
| 0: Repair cost
 +
| The repair's cost in xp levels
 +
|-
 +
| rowspan="2"| Brewing Stand
 +
| 0: Brew time
 +
| 0 – 400, with 400 making the arrow empty, and 0 making the arrow full
 +
|-
 +
| 1: Fuel time
 +
| 0 - 20, with 0 making the arrow empty, and 20 making the arrow full
 
  |-
 
  |-
  | State ID
+
  | Stonecutter
  | VarInt
+
  | 0: Selected recipe
  | The last received State ID from either a [[#Set Container Slot|Set Container Slot]] or a [[#Set Container Content|Set Container Content]] packet
+
  | The index of the selected recipe. -1 means none is selected.
 
  |-
 
  |-
  | Slot
+
  | Loom
  | Short
+
  | 0: Selected pattern
  | The slot that should be updated.
+
  | The index of the selected pattern. 0 means none is selected, 0 is also the internal id of the "base" pattern.
 
  |-
 
  |-
  | Slot Data
+
  | Lectern
  | [[Slot Data|Slot]]
+
  | 0: Page number
  |
+
  | The current page number, starting from 0.
 
  |}
 
  |}
  
To set the cursor (the item currently dragged with the mouse), use -1 as Window ID and as Slot.
+
For an enchanting table, the following numerical IDs are used:
 
 
This packet can only be used to edit the hotbar and offhand of the player's inventory if window ID is set to 0 (slots 36 through 45) if the player is in creative, with their inventory open, and not in their survival inventory tab.  Otherwise, when window ID is 0, it can edit any slot in the player's inventory.  If the window ID is set to -2, then any slot in the inventory can be used but no add item animation will be played.
 
 
 
==== Set Cooldown ====
 
 
 
Applies a cooldown period to all items with the given type.  Used by the Notchian server with enderpearls.  This packet should be sent when the cooldown starts and also when the cooldown ends (to compensate for lag), although the client will end the cooldown automatically. Can be applied to any item, note that interactions still get sent to the server with the item but the client does not play the animation nor attempt to predict results (i.e block placing).
 
  
 
{| class="wikitable"
 
{| class="wikitable"
  ! Packet ID
+
  ! Numerical ID
  ! State
+
  ! Enchantment ID
  ! Bound To
+
  ! Enchantment Name
  ! Field Name
+
|-
  ! Field Type
+
  | 0
  ! Notes
+
  | minecraft:protection
 +
  | Protection
 
  |-
 
  |-
  | rowspan="2"| 0x16
+
  | 1
| rowspan="2"| Play
+
  | minecraft:fire_protection
| rowspan="2"| Client
+
  | Fire Protection
| Item ID
 
  | VarInt
 
  | Numeric ID of the item to apply a cooldown to.
 
 
  |-
 
  |-
  | Cooldown Ticks
+
  | 2
  | VarInt
+
  | minecraft:feather_falling
  | Number of ticks to apply a cooldown for, or 0 to clear the cooldown.
+
  | Feather Falling
|}
 
 
 
==== Chat Suggestions ====
 
 
 
Unused by the Notchian server. Likely provided for custom servers to send chat message completions to clients.
 
 
 
{| class="wikitable"
 
! Packet ID
 
! State
 
! Bound To
 
! Field Name
 
! Field Type
 
! Notes
 
 
  |-
 
  |-
  | rowspan="3"| 0x17
+
  | 3
  | rowspan="3"| Play
+
  | minecraft:blast_protection
| rowspan="3"| Client
+
  | Blast Protection
  | Action
 
| VarInt Enum
 
| 0: Add, 1: Remove, 2: Set
 
 
  |-
 
  |-
  | Count
+
  | 4
  | VarInt
+
  | minecraft:projectile_protection
  | Number of elements in the following array.
+
  | Projectile Protection
 
  |-
 
  |-
  | Entries
+
  | 5
  | Array of String (32767)
+
  | minecraft:respiration
|
+
| Respiration
|}
 
 
 
==== Clientbound Plugin Message (play) ====
 
 
 
{{Main|Plugin channels}}
 
 
 
Mods and plugins can use this to send their data. Minecraft itself uses several [[plugin channel]]s. These internal channels are in the <code>minecraft</code> namespace.
 
 
 
More information on how it works on [https://dinnerbone.com/blog/2012/01/13/minecraft-plugin-channels-messaging/ Dinnerbone's blog]. More documentation about internal and popular registered channels are [[plugin channel|here]].
 
 
 
{| class="wikitable"
 
! Packet ID
 
! State
 
! Bound To
 
! Field Name
 
! Field Type
 
! Notes
 
 
  |-
 
  |-
  | rowspan="2"| 0x18
+
  | 6
| rowspan="2"| Play
+
  | minecraft:aqua_affinity
| rowspan="2"| Client
+
  | Aqua Affinity
| Channel
 
  | Identifier
 
  | Name of the [[plugin channel]] used to send the data.
 
 
  |-
 
  |-
  | Data
+
  | 7
  | Byte Array (1048576)
+
  | minecraft:thorns
  | Any data. The length of this array must be inferred from the packet length.
+
  | Thorns
|}
 
 
 
In Notchian client, the maximum data length is 1048576 bytes.
 
 
 
==== Damage Event ====
 
 
 
{| class="wikitable"
 
! Packet ID
 
! State
 
! Bound To
 
! colspan="2"| Field Name
 
! colspan="2"| Field Type
 
! Notes
 
 
  |-
 
  |-
  | rowspan="9"| 0x19
+
  | 8
  | rowspan="9"| Play
+
  | minecraft:depth_strider
  | rowspan="9"| Client
+
  | Depth Strider
 
  |-
 
  |-
  | colspan="2"| Entity ID
+
  | 9
  | colspan="2"| VarInt
+
  | minecraft:frost_walker
  | The ID of the entity taking damage
+
  | Frost Walker
 
  |-
 
  |-
  | colspan="2"| Source Type ID
+
  | 10
  | colspan="2"| VarInt
+
  | minecraft:binding_curse
  | The type of damage in the <code>minecraft:damage_type</code> registry, defined by the [[Protocol#Registry_Data|Registry Data]] packet.
+
  | Curse of Binding
 
  |-
 
  |-
  | colspan="2"| Source Cause ID
+
  | 11
  | colspan="2"| VarInt
+
| minecraft:soul_speed
  | The ID + 1 of the entity responsible for the damage, if present. If not present, the value is 0
+
| Soul Speed
 +
  |-
 +
| 12
 +
| minecraft:swift_sneak
 +
  | Swift Sneak
 
  |-
 
  |-
  | colspan="2"| Source Direct ID
+
  | 13
  | colspan="2"| VarInt
+
  | minecraft:sharpness
  | The ID + 1 of the entity that directly dealt the damage, if present. If not present, the value is 0. If this field is present:
+
  | Sharpness
* and damage was dealt indirectly, such as by the use of a projectile, this field will contain the ID of such projectile;
 
* and damage was dealt dirctly, such as by manually attacking, this field will contain the same value as Source Cause ID.
 
 
  |-
 
  |-
  | colspan="2"| Has Source Position
+
  | 14
  | colspan="2"| Boolean
+
  | minecraft:smite
  | Indicates the presence of the three following fields.
+
  | Smite
The Notchian server sends the Source Position when the damage was dealt by the /damage command and a position was specified
 
 
  |-
 
  |-
  | colspan="2"| Source Position X
+
  | 15
  | colspan="2"| Optional Double
+
  | minecraft:bane_of_arthropods
  | Only present if Has Source Position is true
+
  | Bane of Arthropods
 
  |-
 
  |-
  | colspan="2"| Source Position Y
+
  | 16
  | colspan="2"| Optional Double
+
  | minecraft:knockback
  | Only present if Has Source Position is true
+
  | Knockback
 
  |-
 
  |-
  | colspan="2"| Source Position Z
+
  | 17
| colspan="2"| Optional Double
+
  | minecraft:fire_aspect
  | Only present if Has Source Position is true
+
  | Fire Aspect
  |}
 
 
 
==== Delete Message ====
 
 
 
Removes a message from the client's chat. This only works for messages with signatures, system messages cannot be deleted with this packet.
 
 
 
{| class="wikitable"
 
! Packet ID
 
! State
 
! Bound To
 
! Field Name
 
! Field Type
 
! Notes
 
 
  |-
 
  |-
  | rowspan="2"| 0x1A
+
  | 18
| rowspan="2"| Play
+
  | minecraft:looting
| rowspan="2"| Client
+
  | Looting
| Message ID
 
  | VarInt
 
  | The message Id + 1, used for validating message signature. The next field is present only when value of this field is equal to 0.
 
 
  |-
 
  |-
  | Signature
+
  | 19
  | Optional Byte Array (256)
+
  | minecraft:sweeping_edge
  | The previous message's signature. Always 256 bytes and not length-prefixed.
+
  | Sweeping Edge
|}
 
 
 
==== Disconnect (play) ====
 
 
 
Sent by the server before it disconnects a client. The client assumes that the server has already closed the connection by the time the packet arrives.
 
 
 
{| class="wikitable"
 
! Packet ID
 
! State
 
! Bound To
 
! Field Name
 
! Field Type
 
! Notes
 
 
  |-
 
  |-
  | 0x1B
+
  | 20
  | Play
+
  | minecraft:efficiency
| Client
+
  | Efficiency
| Reason
 
| [[#Definitions:chat|Chat]]
 
| Displayed to the client when the connection terminates.
 
  |}
 
 
 
==== Disguised Chat Message ====
 
 
 
Sends the client a chat message, but without any message signing information.
 
 
 
The Notchian server uses this packet when the console is communicating with players through commands, such as <code>/say</code>, <code>/tell</code>, <code>/me</code>, among others.
 
 
 
{| class="wikitable
 
! Packet ID
 
! State
 
! Bound To
 
! Field Name
 
! Field Type
 
! Notes
 
 
  |-
 
  |-
  | rowspan="5"| 0x1C
+
  | 21
| rowspan="5"| Play
+
  | minecraft:silk_touch
| rowspan="5"| Client
+
  | Silk Touch
| Message
 
  | Chat
 
  | This is used as the <code>content</code> parameter when formatting the message on the client.
 
 
  |-
 
  |-
  | Chat Type
+
  | 22
  | VarInt
+
  | minecraft:unbreaking
  | The type of chat in the <code>minecraft:chat_type</code> registry, defined by the [[Protocol#Registry_Data|Registry Data]] packet.
+
  | Unbreaking
 
  |-
 
  |-
  | Sender Name
+
  | 23
  | Chat
+
  | minecraft:fortune
  | The name of the one sending the message, usually the sender's display name.
+
  | Fortune
This is used as the <code>sender</code> parameter when formatting the message on the client.
 
 
  |-
 
  |-
  | Has Target Name
+
  | 24
  | Boolean
+
  | minecraft:power
  | True if target name is present.
+
  | Power
 
  |-
 
  |-
  | Target Name
+
  | 25
  | Chat
+
  | minecraft:punch
  | The name of the one receiving the message, usually the receiver's display name. Only present if previous boolean is true.
+
  | Punch
This is used as the <code>target</code> parameter when formatting the message on the client.
 
|}
 
 
 
==== Entity Event ====
 
 
 
Entity statuses generally trigger an animation for an entity.  The available statuses vary by the entity's type (and are available to subclasses of that type as well).
 
 
 
{| class="wikitable"
 
! Packet ID
 
! State
 
! Bound To
 
! Field Name
 
! Field Type
 
! Notes
 
 
  |-
 
  |-
  | rowspan="2"| 0x1D
+
  | 26
| rowspan="2"| Play
+
  | minecraft:flame
| rowspan="2"| Client
+
  | Flame
| Entity ID
 
  | Int
 
  |
 
 
  |-
 
  |-
  | Entity Status
+
  | 27
  | Byte Enum
+
  | minecraft:infinity
  | See [[Entity statuses]] for a list of which statuses are valid for each type of entity.
+
  | Infinity
|}
 
 
 
==== Explosion ====
 
 
 
Sent when an explosion occurs (creepers, TNT, and ghast fireballs).
 
 
 
Each block in Records is set to air. Coordinates for each axis in record is int(X) + record.x
 
 
 
{| class="wikitable"
 
! Packet ID
 
! State
 
! Bound To
 
! Field Name
 
! Field Type
 
! Notes
 
 
  |-
 
  |-
  | rowspan="9"| 0x1E
+
  | 28
| rowspan="9"| Play
+
  | minecraft:luck_of_the_sea
| rowspan="9"| Client
+
  | Luck of the Sea
| X
 
  | Double
 
  |
 
 
  |-
 
  |-
  | Y
+
  | 29
  | Double
+
  | minecraft:lure
  |
+
  | Lure
 +
|-
 +
| 30
 +
| minecraft:loyalty
 +
| Loyalty
 +
|-
 +
| 31
 +
| minecraft:impaling
 +
| Impaling
 +
|-
 +
| 32
 +
| minecraft:riptide
 +
| Riptide
 +
|-
 +
| 33
 +
| minecraft:channeling
 +
| Channeling
 
  |-
 
  |-
  | Z
+
  | 34
  | Double
+
  | minecraft:multishot
  |
+
  | Multishot
 
  |-
 
  |-
  | Strength
+
  | 35
  | Float
+
  | minecraft:quick_charge
  | A strength greater than or equal to 2.0 spawns a <code>minecraft:explosion_emitter</code> particle, while a lesser strength spawns a <code>minecraft:explosion</code> particle.
+
  | Quick Charge
 
  |-
 
  |-
  | Record Count
+
  | 36
  | VarInt
+
  | minecraft:piercing
  | Number of elements in the following array.
+
  | Piercing
 +
|-
 +
| 37
 +
| minecraft:density
 +
| Density
 
  |-
 
  |-
  | Records
+
  | 38
  | Array of (Byte, Byte, Byte)
+
  | minecraft:breach
  | Each record is 3 signed bytes long; the 3 bytes are the XYZ (respectively) signed offsets of affected blocks.
+
  | Breach
 
  |-
 
  |-
  | Player Motion X
+
  | 39
  | Float
+
  | minecraft:wind_burst
  | X velocity of the player being pushed by the explosion.
+
  | Wind Burst
 
  |-
 
  |-
  | Player Motion Y
+
  | 40
  | Float
+
  | minecraft:mending
  | Y velocity of the player being pushed by the explosion.
+
  | Mending
 
  |-
 
  |-
  | Player Motion Z
+
  | 41
  | Float
+
  | minecraft:vanishing_curse
  | Z velocity of the player being pushed by the explosion.
+
  | Curse of Vanishing
 
  |}
 
  |}
  
==== Unload Chunk ====
+
==== Set Container Slot ====
  
Tells the client to unload a chunk column.
+
Sent by the server when an item in a slot (in a window) is added/removed.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 2,685: Line 2,853:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="2"| 0x1F
+
  | rowspan="4"| 0x15
  | rowspan="2"| Play
+
  | rowspan="4"| Play
  | rowspan="2"| Client
+
  | rowspan="4"| Client
  | Chunk Z
+
  | Window ID
  | Int
+
  | {{Type|Byte}}
  | Block coordinate divided by 16, rounded down.
+
  | The window which is being updated. 0 for player inventory. The client ignores any packets targeting a Window ID other than the current one; see below for exceptions.
 
  |-
 
  |-
  | Chunk X
+
  | State ID
  | Int
+
  | {{Type|VarInt}}
  | Block coordinate divided by 16, rounded down.
+
| A server-managed sequence number used to avoid desynchronization; see [[#Click Container]].
 +
|-
 +
| Slot
 +
| {{Type|Short}}
 +
  | The slot that should be updated.
 +
|-
 +
| Slot Data
 +
| {{Type|Slot}}
 +
|
 
  |}
 
  |}
  
Note: The order is inverted, because the client reads this packet as one big-endian Long, with Z being the upper 32 bits.
+
If Window ID is 0, the hotbar and offhand slots (slots 36 through 45) may be updated even when a different container window is open. (The Notchian server does not appear to utilize this special case.) Updates are also restricted to those slots when the player is looking at a creative inventory tab other than the survival inventory. (The Notchian server does ''not'' handle this restriction in any way, leading to [https://bugs.mojang.com/browse/MC-242392 MC-242392].)
 +
 
 +
If Window ID is -1, the item being dragged with the mouse is set. In this case, State ID and Slot are ignored.
 +
 
 +
If Window ID is -2, any slot in the player's inventory can be updated irrespective of the current container window. In this case, State ID is ignored, and the Notchian server uses a bogus value of 0. Used by the Notchian server to implement the [[#Pick Item]] functionality.
  
It is legal to send this packet even if the given chunk is not currently loaded.
+
When a container window is open, the server never sends updates targeting Window ID 0&mdash;all of the [[Inventory|window types]] include slots for the player inventory. The client must automatically apply changes targeting the inventory portion of a container window to the main inventory; the server does not resend them for ID 0 when the window is closed. However, since the armor and offhand slots are only present on ID 0, updates to those slots occurring while a window is open must be deferred by the server until the window's closure.
 +
 
 +
==== Cookie Request (play) ====
 +
 
 +
Requests a cookie that was previously stored.
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! colspan="2"| Field Name
 +
! colspan="2"| Field Type
 +
! Notes
 +
|-
 +
| rowspan="1"| 0x16
 +
| rowspan="1"| Play
 +
| rowspan="1"| Client
 +
| colspan="2"| Key
 +
| colspan="2"| {{Type|Identifier}}
 +
| The identifier of the cookie.
 +
|}
  
==== Game Event ====
+
==== Set Cooldown ====
  
Used for a wide variety of game events, from weather to bed use to game mode to demo messages.
+
Applies a cooldown period to all items with the given type.  Used by the Notchian server with enderpearls.  This packet should be sent when the cooldown starts and also when the cooldown ends (to compensate for lag), although the client will end the cooldown automatically. Can be applied to any item, note that interactions still get sent to the server with the item but the client does not play the animation nor attempt to predict results (i.e block placing).
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 2,713: Line 2,913:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="2"| 0x20
+
  | rowspan="2"| 0x17
 
  | rowspan="2"| Play
 
  | rowspan="2"| Play
 
  | rowspan="2"| Client
 
  | rowspan="2"| Client
  | Event
+
  | Item ID
  | Unsigned Byte
+
  | {{Type|VarInt}}
  | See below.
+
  | Numeric ID of the item to apply a cooldown to.
 
  |-
 
  |-
  | Value
+
  | Cooldown Ticks
  | Float
+
  | {{Type|VarInt}}
  | Depends on Event.
+
  | Number of ticks to apply a cooldown for, or 0 to clear the cooldown.
 
  |}
 
  |}
  
''Events'':
+
==== Chat Suggestions ====
 +
 
 +
Unused by the Notchian server. Likely provided for custom servers to send chat message completions to clients.
  
 
{| class="wikitable"
 
{| class="wikitable"
  ! Event
+
  ! Packet ID
  ! Effect
+
  ! State
  ! Value
+
  ! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 
  |-
 
  |-
  | 0
+
  | rowspan="3"| 0x18
  | No respawn block available
+
| rowspan="3"| Play
  | Note: Displays message 'block.minecraft.spawn.not_valid' (You have no home bed or charged respawn anchor, or it was obstructed) to the player.
+
| rowspan="3"| Client
 +
| Action
 +
  | {{Type|VarInt}} {{Type|Enum}}
 +
  | 0: Add, 1: Remove, 2: Set
 
  |-
 
  |-
  | 1
+
  | Count
  | Begin raining
+
  | {{Type|VarInt}}
  |
+
  | Number of elements in the following array.
 
  |-
 
  |-
  | 2
+
  | Entries
  | End raining
+
  | {{Type|Array}} of {{Type|String}} (32767)
 
  |
 
  |
|-
 
| 3
 
| Change game mode
 
| 0: Survival, 1: Creative, 2: Adventure, 3: Spectator.
 
|-
 
| 4
 
| Win game
 
| 0: Just respawn player.<br>1: Roll the credits and respawn player.<br>Note that 1 is only sent by notchian server when player has not yet achieved advancement "The end?", else 0 is sent.
 
|-
 
| 5
 
| Demo event
 
| 0: Show welcome to demo screen.<br>101: Tell movement controls.<br>102: Tell jump control.<br>103: Tell inventory control.<br>104: Tell that the demo is over and print a message about how to take a screenshot.
 
|-
 
| 6
 
| Arrow hit player
 
| Note: Sent when any player is struck by an arrow.
 
|-
 
| 7
 
| Rain level change
 
| Note: Seems to change both sky color and lighting.<br>Rain level ranging from 0 to 1.
 
|-
 
| 8
 
| Thunder level change
 
| Note: Seems to change both sky color and lighting (same as Rain level change, but doesn't start rain). It also requires rain to render by notchian client.<br>Thunder level ranging from 0 to 1.
 
|-
 
| 9
 
| Play pufferfish sting sound
 
|-
 
| 10
 
| Play elder guardian mob appearance (effect and sound)
 
|
 
|-
 
| 11
 
| Enable respawn screen
 
|  0: Enable respawn screen.<br>1: Immediately respawn (sent when the <code>doImmediateRespawn</code> gamerule changes).
 
|-
 
| 12
 
| Limited crafting
 
| 0: Disable limited crafting.<br>1: Enable limited crafting (sent when the <code>doLimitedCrafting</code> gamerule changes).
 
 
  |}
 
  |}
  
==== Open Horse Screen ====
+
==== Clientbound Plugin Message (play) ====
 +
 
 +
{{Main|Plugin channels}}
 +
 
 +
Mods and plugins can use this to send their data. Minecraft itself uses several [[plugin channel]]s. These internal channels are in the <code>minecraft</code> namespace.
  
This packet is used exclusively for opening the horse GUI. [[#Open Screen|Open Screen]] is used for all other GUIs.  The client will not open the inventory if the Entity ID does not point to an horse-like animal.
+
More information on how it works on [https://dinnerbone.com/blog/2012/01/13/minecraft-plugin-channels-messaging/ Dinnerbone's blog]. More documentation about internal and popular registered channels are [[plugin channel|here]].
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 2,796: Line 2,969:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="3"| 0x21
+
  | rowspan="2"| 0x19
  | rowspan="3"| Play
+
  | rowspan="2"| Play
  | rowspan="3"| Client
+
  | rowspan="2"| Client
  | Window ID
+
  | Channel
  | Unsigned Byte
+
  | {{Type|Identifier}}
  |
+
  | Name of the [[plugin channel]] used to send the data.
 
  |-
 
  |-
  | Slot count
+
  | Data
  | VarInt
+
  | {{Type|Byte Array}} (1048576)
|
+
  | Any data. The length of this array must be inferred from the packet length.
|-
 
| Entity ID
 
| Int
 
  |
 
 
  |}
 
  |}
  
==== Hurt Animation ====
+
In Notchian client, the maximum data length is 1048576 bytes.
  
Plays a bobbing animation for the entity receiving damage.
+
==== Damage Event ====
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 2,824: Line 2,993:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="3"| 0x22
+
  | rowspan="9"| 0x1A
  | rowspan="3"| Play
+
  | rowspan="9"| Play
  | rowspan="3"| Client
+
  | rowspan="9"| Client
 
  |-
 
  |-
 
  | colspan="2"| Entity ID
 
  | colspan="2"| Entity ID
  | colspan="2"| VarInt
+
  | colspan="2"| {{Type|VarInt}}
 
  | The ID of the entity taking damage
 
  | The ID of the entity taking damage
 
  |-
 
  |-
  | colspan="2"| Yaw
+
  | colspan="2"| Source Type ID
  | colspan="2"| Float
+
  | colspan="2"| {{Type|VarInt}}
  | The direction the damage is coming from in relation to the entity
+
| The type of damage in the <code>minecraft:damage_type</code> registry, defined by the [[Protocol#Registry_Data|Registry Data]] packet.
 +
|-
 +
| colspan="2"| Source Cause ID
 +
| colspan="2"| {{Type|VarInt}}
 +
  | The ID + 1 of the entity responsible for the damage, if present. If not present, the value is 0
 +
|-
 +
| colspan="2"| Source Direct ID
 +
| colspan="2"| {{Type|VarInt}}
 +
| The ID + 1 of the entity that directly dealt the damage, if present. If not present, the value is 0. If this field is present:
 +
* and damage was dealt indirectly, such as by the use of a projectile, this field will contain the ID of such projectile;
 +
* and damage was dealt dirctly, such as by manually attacking, this field will contain the same value as Source Cause ID.
 +
|-
 +
| colspan="2"| Has Source Position
 +
| colspan="2"| {{Type|Boolean}}
 +
| Indicates the presence of the three following fields.
 +
The Notchian server sends the Source Position when the damage was dealt by the /damage command and a position was specified
 +
|-
 +
| colspan="2"| Source Position X
 +
| colspan="2"| {{Type|Optional}} {{Type|Double}}
 +
| Only present if Has Source Position is true
 +
|-
 +
| colspan="2"| Source Position Y
 +
| colspan="2"| {{Type|Optional}} {{Type|Double}}
 +
| Only present if Has Source Position is true
 +
|-
 +
| colspan="2"| Source Position Z
 +
| colspan="2"| {{Type|Optional}} {{Type|Double}}
 +
| Only present if Has Source Position is true
 
  |}
 
  |}
  
==== Initialize World Border ====
+
==== Debug Sample ====
 +
 
 +
Sample data that is sent periodically after the client has subscribed with [[#Debug_Sample_Subscription|Debug Sample Subscription]].
 +
 
 +
The Notchian server only sends debug samples to players that are server operators.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 2,847: Line 3,047:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="8"| 0x23
+
  | rowspan="3"| 0x1B
  | rowspan="8"| Play
+
  | rowspan="3"| Play
  | rowspan="8"| Client
+
  | rowspan="3"| Client
  | X
+
  | Sample Length
  | Double
+
  | {{Type|VarInt}}
  |
+
| The length of the following array.
 +
|-
 +
| Sample
 +
| {{Type|Long Array}}
 +
  | Array of type-dependent samples.
 
  |-
 
  |-
  | Z
+
  | Sample Type
  | Double
+
  | {{Type|VarInt}} {{Type|Enum}}
|
+
  | See below.
|-
 
| Old Diameter
 
| Double
 
| Current length of a single side of the world border, in meters.
 
|-
 
| New Diameter
 
| Double
 
| Target length of a single side of the world border, in meters.
 
|-
 
| Speed
 
| VarLong
 
| Number of real-time ''milli''seconds until New Diameter is reached. It appears that Notchian server does not sync world border speed to game ticks, so it gets out of sync with server lag. If the world border is not moving, this is set to 0.
 
|-
 
| Portal Teleport Boundary
 
| VarInt
 
| Resulting coordinates from a portal teleport are limited to ±value. Usually 29999984.
 
|-
 
| Warning Blocks
 
| VarInt
 
| In meters.
 
|-
 
| Warning Time
 
| VarInt
 
  | In seconds as set by <code>/worldborder warning time</code>.
 
 
  |}
 
  |}
  
The Notchian client determines how solid to display the warning by comparing to whichever is higher, the warning distance or whichever is lower, the distance from the current diameter to the target diameter or the place the border will be after warningTime seconds. In pseudocode:
+
Types:
  
<syntaxhighlight lang="java">
+
{| class="wikitable"
distance = max(min(resizeSpeed * 1000 * warningTime, abs(targetDiameter - currentDiameter)), warningDistance);
+
! Id !! Name !! Description
if (playerDistance < distance) {
+
|-
    warning = 1.0 - playerDistance / distance;
+
| 0 || Tick time || Four different tick-related metrics, each one represented by one long on the array.
} else {
+
They are measured in nano-seconds, and are as follows:
    warning = 0.0;
+
* 0: Full tick time: Aggregate of the three times below;
}
+
* 1: Server tick time: Main server tick logic;
</syntaxhighlight>
+
* 2: Tasks time: Tasks scheduled to execute after the main logic;
 +
* 3: Idle time: Time idling to complete the full 50ms tick cycle.
 +
Note that the Notchian client calculates the timings used for min/max/average display by subtracting the idle time from the full tick time. This can cause the displayed values to go negative if the idle time is (nonsensically) greater than the full tick time.
 +
|}
  
==== Clientbound Keep Alive (play) ====
+
==== Delete Message ====
  
The server will frequently send out a keep-alive, each containing a random ID. The client must respond with the same payload (see [[#Serverbound Keep Alive (play)|Serverbound Keep Alive]]). If the client does not respond to them for over 30 seconds, the server kicks the client. Vice versa, if the server does not send any keep-alives for 20 seconds, the client will disconnect and yields a "Timed out" exception.
+
Removes a message from the client's chat. This only works for messages with signatures, system messages cannot be deleted with this packet.
 
 
The Notchian server uses a system-dependent time in milliseconds to generate the keep alive ID value.
 
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 2,908: Line 3,089:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | 0x24
+
  | rowspan="2"| 0x1C
  | Play
+
  | rowspan="2"| Play
  | Client
+
  | rowspan="2"| Client
  | Keep Alive ID
+
  | Message ID
  | Long
+
  | {{Type|VarInt}}
  |
+
| The message Id + 1, used for validating message signature. The next field is present only when value of this field is equal to 0.
 +
|-
 +
| Signature
 +
| {{Type|Optional}} {{Type|Byte Array}} (256)
 +
  | The previous message's signature. Always 256 bytes and not length-prefixed.
 
  |}
 
  |}
  
==== Chunk Data and Update Light ====
+
==== Disconnect (play) ====
{{Main|Chunk Format}}
 
{{See also|#Unload Chunk}}
 
  
This packet sends all block entities in the chunk (though sending them is not required; it is still legal to send them with [[#Block Entity Data|Block Entity Data]] later). The light data in this packet is the same format as in the [[#Update Light|Update Light]] packet.
+
Sent by the server before it disconnects a client. The client assumes that the server has already closed the connection by the time the packet arrives.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 2,926: Line 3,109:
 
  ! State
 
  ! State
 
  ! Bound To
 
  ! Bound To
  ! colspan="2"| Field Name
+
  ! Field Name
  ! colspan="2"| Field Type
+
  ! Field Type
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="20"| 0x25
+
  | ''protocol:''<br/><code>0x1D</code><br/><br/>''resource:''<br/><code>disconnect</code>
  | rowspan="20"| Play
+
| Play
  | rowspan="20"| Client
+
  | Client
  | colspan="2"| Chunk X
+
| Reason
| colspan="2"| Int
+
  | {{Type|Text Component}}
  | Chunk coordinate (block coordinate divided by 16, rounded down)
+
| Displayed to the client when the connection terminates.
 +
  |}
 +
 
 +
==== Disguised Chat Message ====
 +
 
 +
{{Main|Chat}}
 +
 
 +
Sends the client a chat message, but without any message signing information.
 +
 
 +
The Notchian server uses this packet when the console is communicating with players through commands, such as <code>/say</code>, <code>/tell</code>, <code>/me</code>, among others.
 +
 
 +
{| class="wikitable
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
  ! Notes
 
  |-
 
  |-
  | colspan="2"| Chunk Z
+
  | rowspan="5"| 0x1E
  | colspan="2"| Int
+
  | rowspan="5"| Play
  | Chunk coordinate (block coordinate divided by 16, rounded down)
+
  | rowspan="5"| Client
 +
| Message
 +
| {{Type|Text Component}}
 +
| This is used as the <code>content</code> parameter when formatting the message on the client.
 
  |-
 
  |-
  | colspan="2"| Heightmaps
+
  | Chat Type
  | colspan="2"| [[NBT]]
+
  | {{Type|VarInt}}
  | See [[Chunk Format#Heightmaps structure]]
+
  | The type of chat in the <code>minecraft:chat_type</code> registry, defined by the [[Protocol#Registry_Data|Registry Data]] packet.
 
  |-
 
  |-
  | colspan="2"| Size
+
  | Sender Name
  | colspan="2"| VarInt
+
  | {{Type|Text Component}}
  | Size of Data in bytes
+
  | The name of the one sending the message, usually the sender's display name.
 +
This is used as the <code>sender</code> parameter when formatting the message on the client.
 
  |-
 
  |-
  | colspan="2"| Data
+
  | Has Target Name
  | colspan="2"| Byte array
+
  | {{Type|Boolean}}
  | See [[Chunk Format#Data structure]]
+
  | True if target name is present.
 
  |-
 
  |-
  | colspan="2"| Number of block entities
+
  | Target Name
| colspan="2"| VarInt
+
  | {{Type|Text Component}}
| Number of elements in the following array
+
  | The name of the one receiving the message, usually the receiver's display name. Only present if previous boolean is true.
|-
+
This is used as the <code>target</code> parameter when formatting the message on the client.
| rowspan="4"| Block Entity
+
  |}
| Packed XZ
+
 
| rowspan="4"| Array
+
==== Entity Event ====
| Byte
 
| The packed section coordinates are relative to the chunk they are in values 0-15 are valid. <pre>packed_xz = ((blockX & 15) << 4) | (blockZ & 15) // encode
 
x = packed_xz >> 4, z = packed_xz & 15 // decode</pre>
 
|-
 
| Y
 
| Short
 
| The height relative to the world
 
|-
 
  | Type
 
| VarInt
 
  | The type of block entity
 
|-
 
| Data
 
| [[NBT]]
 
| The block entity's data, without the X, Y, and Z values
 
|-
 
| colspan="2"| Sky Light Mask
 
| colspan="2"| BitSet
 
| BitSet containing bits for each section in the world + 2.  Each set bit indicates that the corresponding 16×16×16 chunk section has data in the Sky Light array below.  The least significant bit is for blocks 16 blocks to 1 block below the min world height (one section below the world), while the most significant bit covers blocks 1 to 16 blocks above the max world height (one section above the world).
 
|-
 
| colspan="2"| Block Light Mask
 
| colspan="2"| BitSet
 
| BitSet containing bits for each section in the world + 2.  Each set bit indicates that the corresponding 16×16×16 chunk section has data in the Block Light array below.  The order of bits is the same as in Sky Light Mask.
 
|-
 
| colspan="2"| Empty Sky Light Mask
 
| colspan="2"| BitSet
 
| BitSet containing bits for each section in the world + 2.  Each set bit indicates that the corresponding 16×16×16 chunk section has all zeros for its Sky Light data.  The order of bits is the same as in Sky Light Mask.
 
|-
 
| colspan="2"| Empty Block Light Mask
 
| colspan="2"| BitSet
 
| BitSet containing bits for each section in the world + 2.  Each set bit indicates that the corresponding 16×16×16 chunk section has all zeros for its Block Light data.  The order of bits is the same as in Sky Light Mask.
 
|-
 
| colspan="2"| Sky Light array count
 
| colspan="2"| VarInt
 
| Number of entries in the following array; should match the number of bits set in Sky Light Mask
 
|-
 
| rowspan="2"| Sky Light arrays
 
| Length
 
| rowspan="2"| Array
 
| VarInt
 
| Length of the following array in bytes (always 2048)
 
|-
 
| Sky Light array
 
| Array of 2048 bytes
 
| There is 1 array for each bit set to true in the sky light mask, starting with the lowest value.  Half a byte per light value. Indexed <code><nowiki>((y<<8) | (z<<4) | x) / 2 </nowiki></code> If there's a remainder, masked 0xF0 else 0x0F.
 
  |-
 
| colspan="2"| Block Light array count
 
| colspan="2"| VarInt
 
| Number of entries in the following array; should match the number of bits set in Block Light Mask
 
|-
 
| rowspan="2"| Block Light arrays
 
| Length
 
| rowspan="2"| Array
 
| VarInt
 
| Length of the following array in bytes (always 2048)
 
|-
 
| Block Light array
 
| Array of 2048 bytes
 
| There is 1 array for each bit set to true in the block light mask, starting with the lowest value.  Half a byte per light value. Indexed <code><nowiki>((y<<8) | (z<<4) | x) / 2 </nowiki></code> If there's a remainder, masked 0xF0 else 0x0F.
 
|}
 
  
Note that the Notchian client requires an [[#Set Center Chunk|Set Center Chunk]] packet when it crosses a chunk border, otherwise it'll only display render distance + 2 chunks around the chunk it spawned in.
+
Entity statuses generally trigger an animation for an entity. The available statuses vary by the entity's type (and are available to subclasses of that type as well).
 
 
==== World Event ====
 
Sent when a client is to play a sound or particle effect.
 
 
 
By default, the Minecraft client adjusts the volume of sound effects based on distance. The final boolean field is used to disable this, and instead the effect is played from 2 blocks away in the correct direction. Currently this is only used for effect 1023 (wither spawn), effect 1028 (enderdragon death), and effect 1038 (end portal opening); it is ignored on other effects.
 
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 3,036: Line 3,175:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="4"| 0x26
+
  | rowspan="2"| 0x1F
  | rowspan="4"| Play
+
  | rowspan="2"| Play
  | rowspan="4"| Client
+
  | rowspan="2"| Client
  | Event
+
  | Entity ID
  | Int
+
  | {{Type|Int}}
  | The event, see below.
+
  |
 
  |-
 
  |-
  | Location
+
  | Entity Status
  | Position
+
  | {{Type|Byte}} {{Type|Enum}}
| The location of the event.
+
  | See [[Entity statuses]] for a list of which statuses are valid for each type of entity.
|-
 
  | Data
 
| Int
 
| Extra data for certain events, see below.
 
|-
 
| Disable Relative Volume
 
| Boolean
 
| See above.
 
 
  |}
 
  |}
  
Events:
+
==== Explosion ====
 +
 
 +
Sent when an explosion occurs (creepers, TNT, and ghast fireballs).
 +
 
 +
Each block in Records is set to air. Coordinates for each axis in record is int(X) + record.x
  
 
{| class="wikitable"
 
{| class="wikitable"
  ! ID
+
  ! Packet ID
  ! Name
+
  ! State
  ! Data
+
! Bound To
 +
! colspan="2" | Field Name
 +
  ! Field Type
 +
! Notes
 
  |-
 
  |-
  ! colspan="3"| Sound
+
  | rowspan="17"| 0x20
  |-
+
  | rowspan="17"| Play
  | 1000
+
  | rowspan="17"| Client
  | Dispenser dispenses
+
  | colspan="2" | X
 +
| {{Type|Double}}
 
  |
 
  |
 
  |-
 
  |-
  | 1001
+
  | colspan="2" | Y
  | Dispenser fails to dispense
+
  | {{Type|Double}}
 
  |
 
  |
 
  |-
 
  |-
  | 1002
+
  | colspan="2" | Z
  | Dispenser shoots
+
  | {{Type|Double}}
 
  |
 
  |
 
  |-
 
  |-
  | 1003
+
  | colspan="2" | Strength
  | Ender eye launched
+
  | {{Type|Float}}
  |
+
  | If the strength is greater or equal to 2.0, or the block interaction is not 0 (keep), large explosion particles are used. Otherwise, small explosion particles are used.
 
  |-
 
  |-
  | 1004
+
  | colspan="2" | Record Count
  | Firework shot
+
  | {{Type|VarInt}}
  |
+
  | Number of elements in the following array.
 
  |-
 
  |-
  | 1005
+
  | colspan="2" | Records
  | Iron door opened
+
  | {{Type|Array}} of ({{Type|Byte}}, {{Type|Byte}}, {{Type|Byte}})
  |
+
  | Each record is 3 signed bytes long; the 3 bytes are the XYZ (respectively) signed offsets of affected blocks.
 
  |-
 
  |-
  | 1006
+
  | colspan="2" | Player Motion X
  | Wooden door opened
+
  | {{Type|Float}}
  |
+
  | X velocity of the player being pushed by the explosion.
 
  |-
 
  |-
  | 1007
+
  | colspan="2" | Player Motion Y
  | Wooden trapdoor opened
+
  | {{Type|Float}}
  |
+
  | Y velocity of the player being pushed by the explosion.
 
  |-
 
  |-
  | 1008
+
  | colspan="2" | Player Motion Z
  | Fence gate opened
+
  | {{Type|Float}}
  |
+
  | Z velocity of the player being pushed by the explosion.
 
  |-
 
  |-
  | 1009
+
  | colspan="2" | Block Interaction
  | Fire extinguished
+
  | {{Type|VarInt}} {{Type|Enum}}
  |
+
  | 0 = keep, 1 = destroy, 2 = destroy_with_decay, 3 = trigger_block.
 
  |-
 
  |-
  | 1010
+
  | colspan="2" | Small Explosion Particle ID
  | Play record
+
  | {{Type|VarInt}}
  | Special case, see below for more info.
+
  | The particle ID listed in [[Particles]].
 
  |-
 
  |-
  | 1011
+
  | colspan="2" | Small Explosion Particle Data
  | Iron door closed
+
  | Varies
  |
+
  | Particle data as specified in [[Particles]].
 
  |-
 
  |-
  | 1012
+
  | colspan="2" | Large Explosion Particle ID
  | Wooden door closed
+
  | {{Type|VarInt}}
  |
+
  | The particle ID listed in [[Particles]].
 
  |-
 
  |-
  | 1013
+
  | colspan="2" | Large Explosion Particle Data
  | Wooden trapdoor closed
+
  | Varies
  |
+
  | Particle data as specified in [[Particles]].
 
  |-
 
  |-
  | 1014
+
  | rowspan="3" | Explosion Sound
  | Fence gate closed
+
  | Sound Name
  |
+
| {{Type|Identifier}}
 +
  | The name of the sound played.
 
  |-
 
  |-
  | 1015
+
  | Has Fixed Range
  | Ghast warns
+
  | {{Type|Optional}} {{Type|Boolean}}
  |
+
  | Whether is has fixed range.
 
  |-
 
  |-
  | 1016
+
  | Range
  | Ghast shoots
+
  | {{Type|Optional}} {{Type|Float}}
  |
+
| The fixed range of the sound. Only present if previous boolean is true.
 +
  |}
 +
 
 +
==== Unload Chunk ====
 +
 
 +
Tells the client to unload a chunk column.
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 
  |-
 
  |-
  | 1017
+
  | rowspan="2"| 0x21
  | Enderdragon shoots
+
  | rowspan="2"| Play
  |
+
| rowspan="2"| Client
 +
| Chunk Z
 +
| {{Type|Int}}
 +
  | Block coordinate divided by 16, rounded down.
 
  |-
 
  |-
  | 1018
+
  | Chunk X
  | Blaze shoots
+
  | {{Type|Int}}
  |
+
  | Block coordinate divided by 16, rounded down.
  |-
+
  |}
| 1019
+
 
  | Zombie attacks wood door
+
Note: The order is inverted, because the client reads this packet as one big-endian {{Type|Long}}, with Z being the upper 32 bits.
  |
+
 
  |-
+
It is legal to send this packet even if the given chunk is not currently loaded.
  | 1020
+
 
  | Zombie attacks iron door
+
==== Game Event ====
  |
+
 
 +
Used for a wide variety of game events, from weather to bed use to game mode to demo messages.
 +
 
 +
{| class="wikitable"
 +
  ! Packet ID
 +
  ! State
 +
  ! Bound To
 +
  ! Field Name
 +
  ! Field Type
 +
  ! Notes
 
  |-
 
  |-
  | 1021
+
  | rowspan="2"| ''protocol:''<br/><code>0x22</code><br/><br/>''resource:''<br/><code>game_event</code>
  | Zombie breaks wood door
+
  | rowspan="2"| Play
  |
+
| rowspan="2"| Client
 +
| Event
 +
| {{Type|Unsigned Byte}}
 +
  | See below.
 
  |-
 
  |-
  | 1022
+
  | Value
  | Wither breaks block
+
  | {{Type|Float}}
  |
+
| Depends on Event.
 +
  |}
 +
 
 +
''Events'':
 +
 
 +
{| class="wikitable"
 +
! Event
 +
! Effect
 +
! Value
 
  |-
 
  |-
  | 1023
+
  | 0
  | Wither spawned
+
  | No respawn block available
  |
+
  | Note: Displays message 'block.minecraft.spawn.not_valid' (You have no home bed or charged respawn anchor, or it was obstructed) to the player.
 
  |-
 
  |-
  | 1024
+
  | 1
  | Wither shoots
+
  | Begin raining
 
  |
 
  |
 
  |-
 
  |-
  | 1025
+
  | 2
  | Bat takes off
+
  | End raining
 
  |
 
  |
 
  |-
 
  |-
  | 1026
+
  | 3
  | Zombie infects
+
  | Change game mode
  |
+
  | 0: Survival, 1: Creative, 2: Adventure, 3: Spectator.
 
  |-
 
  |-
  | 1027
+
  | 4
  | Zombie villager converted
+
  | Win game
  |
+
  | 0: Just respawn player.<br>1: Roll the credits and respawn player.<br>Note that 1 is only sent by notchian server when player has not yet achieved advancement "The end?", else 0 is sent.
 
  |-
 
  |-
  | 1028
+
  | 5
  | Ender dragon death
+
  | Demo event
  |
+
  | 0: Show welcome to demo screen.<br>101: Tell movement controls.<br>102: Tell jump control.<br>103: Tell inventory control.<br>104: Tell that the demo is over and print a message about how to take a screenshot.
 
  |-
 
  |-
  | 1029
+
  | 6
  | Anvil destroyed
+
  | Arrow hit player
  |
+
  | Note: Sent when any player is struck by an arrow.
 
  |-
 
  |-
  | 1030
+
  | 7
  | Anvil used
+
  | Rain level change
  |
+
  | Note: Seems to change both sky color and lighting.<br>Rain level ranging from 0 to 1.
 
  |-
 
  |-
  | 1031
+
  | 8
  | Anvil landed
+
  | Thunder level change
  |
+
  | Note: Seems to change both sky color and lighting (same as Rain level change, but doesn't start rain). It also requires rain to render by notchian client.<br>Thunder level ranging from 0 to 1.
 
  |-
 
  |-
  | 1032
+
  | 9
| Portal travel
+
  | Play pufferfish sting sound
  |
 
 
  |-
 
  |-
  | 1033
+
  | 10
  | Chorus flower grown
+
  | Play elder guardian mob appearance (effect and sound)
 
  |
 
  |
 
  |-
 
  |-
  | 1034
+
  | 11
  | Chorus flower died
+
  | Enable respawn screen
  |
+
  | 0: Enable respawn screen.<br>1: Immediately respawn (sent when the <code>doImmediateRespawn</code> gamerule changes).
 
  |-
 
  |-
  | 1035
+
  | 12
  | Brewing stand brewed
+
  | Limited crafting
  |
+
  | 0: Disable limited crafting.<br>1: Enable limited crafting (sent when the <code>doLimitedCrafting</code> gamerule changes).
 
  |-
 
  |-
  | 1036
+
  | 13
  | Iron trapdoor opened
+
  | Start waiting for level chunks
  |
+
  | Instructs the client to begin the waiting process for the level chunks.<br>Sent by the server after the level is cleared on the client and is being re-sent (either during the first, or subsequent reconfigurations).
  |-
+
  |}
| 1037
+
 
  | Iron trapdoor closed
+
==== Open Horse Screen ====
  |
+
 
  |-
+
This packet is used exclusively for opening the horse GUI. [[#Open Screen|Open Screen]] is used for all other GUIs.  The client will not open the inventory if the Entity ID does not point to an horse-like animal.
  | 1038
+
 
  | End portal created in overworld
+
{| class="wikitable"
  |
+
  ! Packet ID
 +
  ! State
 +
  ! Bound To
 +
  ! Field Name
 +
  ! Field Type
 +
  ! Notes
 
  |-
 
  |-
  | 1039
+
  | rowspan="3"| 0x23
  | Phantom bites
+
  | rowspan="3"| Play
 +
| rowspan="3"| Client
 +
| Window ID
 +
| {{Type|Unsigned Byte}}
 
  |
 
  |
 
  |-
 
  |-
  | 1040
+
  | Slot count
  | Zombie converts to drowned
+
  | {{Type|VarInt}}
 
  |
 
  |
 
  |-
 
  |-
  | 1041
+
  | Entity ID
  | Husk converts to zombie by drowning
+
  | {{Type|Int}}
 
  |
 
  |
 +
|}
 +
 +
==== Hurt Animation ====
 +
 +
Plays a bobbing animation for the entity receiving damage.
 +
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! colspan="2"| Field Name
 +
! colspan="2"| Field Type
 +
! Notes
 
  |-
 
  |-
  | 1042
+
  | rowspan="3"| 0x24
  | Grindstone used
+
  | rowspan="3"| Play
  |
+
  | rowspan="3"| Client
 
  |-
 
  |-
  | 1043
+
  | colspan="2"| Entity ID
  | Book page turned
+
  | colspan="2"| {{Type|VarInt}}
  |
+
  | The ID of the entity taking damage
 
  |-
 
  |-
 +
| colspan="2"| Yaw
 +
| colspan="2"| {{Type|Float}}
 +
| The direction the damage is coming from in relation to the entity
 +
|}
 +
 +
==== Initialize World Border ====
 +
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 
  |-
 
  |-
  ! colspan="3"| Particle
+
  | rowspan="8"| 0x25
  |-
+
  | rowspan="8"| Play
  | 1500
+
  | rowspan="8"| Client
  | Composter composts
+
| X
 +
  | {{Type|Double}}
 
  |
 
  |
 
  |-
 
  |-
  | 1501
+
  | Z
  | Lava converts block (either water to stone, or removes existing blocks such as torches)
+
  | {{Type|Double}}
 
  |
 
  |
 
  |-
 
  |-
  | 1502
+
  | Old Diameter
  | Redstone torch burns out
+
  | {{Type|Double}}
  |
+
  | Current length of a single side of the world border, in meters.
 
  |-
 
  |-
  | 1503
+
  | New Diameter
  | Ender eye placed
+
  | {{Type|Double}}
  |
+
  | Target length of a single side of the world border, in meters.
 
  |-
 
  |-
  | 2000
+
  | Speed
  | Spawns 10 smoke particles, e.g. from a fire
+
  | {{Type|VarLong}}
  | Direction, see below.
+
  | Number of real-time ''milli''seconds until New Diameter is reached. It appears that Notchian server does not sync world border speed to game ticks, so it gets out of sync with server lag. If the world border is not moving, this is set to 0.
 
  |-
 
  |-
  | 2001
+
  | Portal Teleport Boundary
  | Block break + block break sound
+
  | {{Type|VarInt}}
  | Block state ID (see [[Chunk Format#Block state registry]]).
+
  | Resulting coordinates from a portal teleport are limited to ±value. Usually 29999984.
 
  |-
 
  |-
  | 2002
+
  | Warning Blocks
  | Splash potion. Particle effect + glass break sound.
+
  | {{Type|VarInt}}
  | RGB color as an integer (e.g. 8364543 for #7FA1FF).
+
  | In meters.
 
  |-
 
  |-
  | 2003
+
  | Warning Time
  | Eye of Ender entity break animation — particles and sound
+
  | {{Type|VarInt}}
  |
+
  | In seconds as set by <code>/worldborder warning time</code>.
  |-
+
  |}
  | 2004
+
 
  | Mob spawn particle effect: smoke + flames
+
The Notchian client determines how solid to display the warning by comparing to whichever is higher, the warning distance or whichever is lower, the distance from the current diameter to the target diameter or the place the border will be after warningTime seconds. In pseudocode:
  |
+
 
  |-
+
<syntaxhighlight lang="java">
  | 2005
+
distance = max(min(resizeSpeed * 1000 * warningTime, abs(targetDiameter - currentDiameter)), warningDistance);
  | Bonemeal particles
+
if (playerDistance < distance) {
  | How many particles to spawn (if set to 0, 15 are spawned).
+
    warning = 1.0 - playerDistance / distance;
  |-
+
} else {
  | 2006
+
    warning = 0.0;
| Dragon breath
+
}
 +
</syntaxhighlight>
 +
 
 +
==== Clientbound Keep Alive (play) ====
 +
 
 +
The server will frequently send out a keep-alive, each containing a random ID. The client must respond with the same payload (see [[#Serverbound Keep Alive (play)|Serverbound Keep Alive]]). If the client does not respond to a Keep Alive packet within 15 seconds after it was sent, the server kicks the client. Vice versa, if the server does not send any keep-alives for 20 seconds, the client will disconnect and yields a "Timed out" exception.
 +
 
 +
The Notchian server uses a system-dependent time in milliseconds to generate the keep alive ID value.
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
  ! Field Name
 +
  ! Field Type
 +
  ! Notes
 +
  |-
 +
  | ''protocol:''<br/><code>0x26</code><br/><br/>''resource:''<br/><code>keep_alive</code>
 +
  | Play
 +
  | Client
 +
  | Keep Alive ID
 +
  | {{Type|Long}}
 
  |
 
  |
 +
|}
 +
 +
==== Chunk Data and Update Light ====
 +
{{Main|Chunk Format}}
 +
{{See also|#Unload Chunk}}
 +
 +
Sent when a chunk comes into the client's view distance, specifying its terrain, lighting and block entities.
 +
 +
The chunk must be within the view area previously specified with [[#Set Center Chunk|Set Center Chunk]]; see that packet for details.
 +
 +
It is not strictly necessary to send all block entities in this packet; it is still legal to send them with [[#Block Entity Data|Block Entity Data]] later.
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! colspan="2"| Field Name
 +
! colspan="2"| Field Type
 +
! Notes
 
  |-
 
  |-
  | 2007
+
  | rowspan="20"| 0x27
  | Instant splash potion. Particle effect + glass break sound.
+
| rowspan="20"| Play
  | RGB color as an integer (e.g. 8364543 for #7FA1FF).
+
  | rowspan="20"| Client
 +
| colspan="2"| Chunk X
 +
| colspan="2"| {{Type|Int}}
 +
  | Chunk coordinate (block coordinate divided by 16, rounded down)
 
  |-
 
  |-
  | 2008
+
  | colspan="2"| Chunk Z
  | Ender dragon destroys block
+
  | colspan="2"| {{Type|Int}}
  |
+
  | Chunk coordinate (block coordinate divided by 16, rounded down)
 
  |-
 
  |-
  | 2009
+
  | colspan="2"| Heightmaps
  | Wet sponge vaporizes in nether
+
  | colspan="2"| [[NBT]]
  |
+
  | See [[Chunk Format#Heightmaps structure]]
 
  |-
 
  |-
  | 3000
+
  | colspan="2"| Size
| End gateway spawn
+
  | colspan="2"| {{Type|VarInt}}
  |
+
  | Size of Data in bytes
|-
 
| 3001
 
| Enderdragon growl
 
  |
 
 
  |-
 
  |-
  | 3002
+
  | colspan="2"| Data
  | Electric spark
+
  | colspan="2"| {{Type|Byte Array}}
  |
+
  | See [[Chunk Format#Data structure]]
 
  |-
 
  |-
  | 3003
+
  | colspan="2"| Number of block entities
  | Copper apply wax
+
  | colspan="2"| {{Type|VarInt}}
  |
+
  | Number of elements in the following array
 
  |-
 
  |-
  | 3004
+
  | rowspan="4"| Block Entity
  | Copper remove wax
+
| Packed XZ
  |
+
| rowspan="4"| {{Type|Array}}
 +
  | {{Type|Unsigned Byte}}
 +
  | The packed section coordinates are relative to the chunk they are in. Values 0-15 are valid. <pre>packed_xz = ((blockX & 15) << 4) | (blockZ & 15) // encode
 +
x = packed_xz >> 4, z = packed_xz & 15 // decode</pre>
 
  |-
 
  |-
  | 3005
+
  | Y
  | Copper scrape oxidation
+
  | {{Type|Short}}
|
+
  | The height relative to the world
  |}
 
 
 
Smoke directions:
 
 
 
{| class="wikitable"
 
! ID
 
! Direction
 
 
  |-
 
  |-
  | 0
+
  | Type
  | Down
+
  | {{Type|VarInt}}
 +
| The type of block entity
 
  |-
 
  |-
  | 1
+
  | Data
  | Up
+
  | [[NBT]]
 +
| The block entity's data, without the X, Y, and Z values
 
  |-
 
  |-
  | 2
+
  | colspan="2"| Sky Light Mask
  | North
+
| colspan="2"| {{Type|BitSet}}
 +
  | BitSet containing bits for each section in the world + 2.  Each set bit indicates that the corresponding 16×16×16 chunk section has data in the Sky Light array below.  The least significant bit is for blocks 16 blocks to 1 block below the min world height (one section below the world), while the most significant bit covers blocks 1 to 16 blocks above the max world height (one section above the world).
 
  |-
 
  |-
  | 3
+
  | colspan="2"| Block Light Mask
  | South
+
| colspan="2"| {{Type|BitSet}}
 +
  | BitSet containing bits for each section in the world + 2.  Each set bit indicates that the corresponding 16×16×16 chunk section has data in the Block Light array below.  The order of bits is the same as in Sky Light Mask.
 
  |-
 
  |-
  | 4
+
  | colspan="2"| Empty Sky Light Mask
  | West
+
| colspan="2"| {{Type|BitSet}}
 +
  | BitSet containing bits for each section in the world + 2.  Each set bit indicates that the corresponding 16×16×16 chunk section has all zeros for its Sky Light data.  The order of bits is the same as in Sky Light Mask.
 
  |-
 
  |-
  | 5
+
  | colspan="2"| Empty Block Light Mask
  | East
+
| colspan="2"| {{Type|BitSet}}
 +
| BitSet containing bits for each section in the world + 2.  Each set bit indicates that the corresponding 16×16×16 chunk section has all zeros for its Block Light data.  The order of bits is the same as in Sky Light Mask.
 +
|-
 +
| colspan="2"| Sky Light array count
 +
| colspan="2"| {{Type|VarInt}}
 +
| Number of entries in the following array; should match the number of bits set in Sky Light Mask
 +
|-
 +
| rowspan="2"| Sky Light arrays
 +
| Length
 +
| rowspan="2"| {{Type|Array}}
 +
| {{Type|VarInt}}
 +
| Length of the following array in bytes (always 2048)
 +
|-
 +
| Sky Light array
 +
| {{Type|Byte Array}} (2048)
 +
| There is 1 array for each bit set to true in the sky light mask, starting with the lowest value.  Half a byte per light value. Indexed <code><nowiki>((y<<8) | (z<<4) | x) / 2 </nowiki></code> If there's a remainder, masked 0xF0 else 0x0F.
 +
  |-
 +
| colspan="2"| Block Light array count
 +
| colspan="2"| {{Type|VarInt}}
 +
| Number of entries in the following array; should match the number of bits set in Block Light Mask
 +
|-
 +
| rowspan="2"| Block Light arrays
 +
| Length
 +
| rowspan="2"| {{Type|Array}}
 +
| {{Type|VarInt}}
 +
| Length of the following array in bytes (always 2048)
 +
|-
 +
| Block Light array
 +
| {{Type|Byte Array}} (2048)
 +
| There is 1 array for each bit set to true in the block light mask, starting with the lowest value.  Half a byte per light value. Indexed <code><nowiki>((y<<8) | (z<<4) | x) / 2 </nowiki></code> If there's a remainder, masked 0xF0 else 0x0F.
 
  |}
 
  |}
  
Play record: This is actually a special case within this packet. You can start/stop a record at a specific location. Use a valid {{Minecraft Wiki|Music Discs|Record ID}} to start a record (or overwrite a currently playing one), any other value will stop the record.  See [[Data Generators]] for information on item IDs.
+
Unlike the [[#Update Light|Update Light]] packet which uses the same format, setting the bit corresponding to a section to 0 in both of the block light or sky light masks does not appear to be useful, and the results in testing have been highly inconsistent.
 +
 
 +
==== World Event ====
 +
 
 +
{{Need Info|The events listed below are not up-to-date with the latest release version, being either improperly documented or missing from the list altogether.}}
  
==== Particle ====
+
Sent when a client is to play a sound or particle effect.
  
Displays the named particle
+
By default, the Minecraft client adjusts the volume of sound effects based on distance. The final boolean field is used to disable this, and instead the effect is played from 2 blocks away in the correct direction. Currently this is only used for effect 1023 (wither spawn), effect 1028 (enderdragon death), and effect 1038 (end portal opening); it is ignored on other effects.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 3,364: Line 3,647:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="11"| 0x27
+
  | rowspan="4"| 0x28
  | rowspan="11"| Play
+
  | rowspan="4"| Play
  | rowspan="11"| Client
+
  | rowspan="4"| Client
  | Particle ID
+
  | Event
  | VarInt
+
  | {{Type|Int}}
  | The particle ID listed in [[#Particle|the particle data type]].
+
  | The event, see below.
 
  |-
 
  |-
  | Long Distance
+
  | Location
  | Boolean
+
  | {{Type|Position}}
  | If true, particle distance increases from 256 to 65536.
+
  | The location of the event.
 
  |-
 
  |-
  | X
+
  | Data
  | Double
+
  | {{Type|Int}}
  | X position of the particle.
+
  | Extra data for certain events, see below.
 
  |-
 
  |-
  | Y
+
  | Disable Relative Volume
  | Double
+
  | {{Type|Boolean}}
  | Y position of the particle.
+
  | See above.
 +
|}
 +
 
 +
Events:
 +
 
 +
{| class="wikitable"
 +
! ID
 +
! Name
 +
! Data
 
  |-
 
  |-
  | Z
+
  ! colspan="3"| Sound
| Double
 
| Z position of the particle.
 
 
  |-
 
  |-
  | Offset X
+
  | 1000
  | Float
+
  | Dispenser dispenses
  | This is added to the X position after being multiplied by <code>random.nextGaussian()</code>.
+
  |
 
  |-
 
  |-
  | Offset Y
+
  | 1001
  | Float
+
  | Dispenser fails to dispense
  | This is added to the Y position after being multiplied by <code>random.nextGaussian()</code>.
+
  |
 
  |-
 
  |-
  | Offset Z
+
  | 1002
  | Float
+
  | Dispenser shoots
  | This is added to the Z position after being multiplied by <code>random.nextGaussian()</code>.
+
  |
 
  |-
 
  |-
  | Max Speed
+
  | 1003
  | Float
+
  | Ender eye launched
 
  |
 
  |
 
  |-
 
  |-
  | Particle Count
+
  | 1004
  | Int
+
  | Firework shot
  | The number of particles to create.
+
  |
 
  |-
 
  |-
  | Data
+
  | 1009
  | Varies
+
  | Fire extinguished
  | The variable data listed in [[#Particle|the particle data type]].
+
  |
|}
 
 
 
==== Update Light ====
 
 
 
Updates light levels for a chunk.  See {{Minecraft Wiki|Light}} for information on how lighting works in Minecraft.
 
 
 
{| class="wikitable"
 
! Packet ID
 
! State
 
! Bound To
 
! colspan="2"| Field Name
 
! colspan="2"| Field Type
 
! Notes
 
 
  |-
 
  |-
  | rowspan="12"| 0x28
+
  | 1010
  | rowspan="12"| Play
+
  | Play record
  | rowspan="12"| Client
+
  | An ID in the <code>minecraft:item</code> registry, corresponding to a {{Minecraft Wiki|Music Disc|record item}}. If the ID doesn't correspond to a record, the packet is ignored. Any record already being played at the given location is overwritten. See [[Data Generators]] for information on item IDs.
| colspan="2"| Chunk X
 
| colspan="2"| VarInt
 
| Chunk coordinate (block coordinate divided by 16, rounded down)
 
 
  |-
 
  |-
  | colspan="2"| Chunk Z
+
  | 1011
  | colspan="2"| VarInt
+
  | Stop record
  | Chunk coordinate (block coordinate divided by 16, rounded down)
+
  |  
 
  |-
 
  |-
  | colspan="2"| Sky Light Mask
+
  | 1015
  | colspan="2"| BitSet
+
  | Ghast warns
  | BitSet containing bits for each section in the world + 2.  Each set bit indicates that the corresponding 16×16×16 chunk section has data in the Sky Light array below.  The least significant bit is for blocks 16 blocks to 1 block below the min world height (one section below the world), while the most significant bit covers blocks 1 to 16 blocks above the max world height (one section above the world).
+
  |
 
  |-
 
  |-
  | colspan="2"| Block Light Mask
+
  | 1016
  | colspan="2"| BitSet
+
| Ghast shoots
  | BitSet containing bits for each section in the world + 2. Each set bit indicates that the corresponding 16×16×16 chunk section has data in the Block Light array below. The order of bits is the same as in Sky Light Mask.
+
|
 +
|-
 +
| 1017
 +
  | Enderdragon shoots
 +
|
 +
|-
 +
  | 1018
 +
  | Blaze shoots
 +
  |
 
  |-
 
  |-
  | colspan="2"| Empty Sky Light Mask
+
  | 1019
  | colspan="2"| BitSet
+
  | Zombie attacks wood door
  | BitSet containing bits for each section in the world + 2.  Each set bit indicates that the corresponding 16×16×16 chunk section has all zeros for its Sky Light data.  The order of bits is the same as in Sky Light Mask.
+
  |
 
  |-
 
  |-
  | colspan="2"| Empty Block Light Mask
+
  | 1020
  | colspan="2"| BitSet
+
  | Zombie attacks iron door
  | BitSet containing bits for each section in the world + 2.  Each set bit indicates that the corresponding 16×16×16 chunk section has all zeros for its Block Light data.  The order of bits is the same as in Sky Light Mask.
+
  |
 
  |-
 
  |-
  | colspan="2"| Sky Light array count
+
  | 1021
  | colspan="2"| VarInt
+
  | Zombie breaks wood door
  | Number of entries in the following array; should match the number of bits set in Sky Light Mask
+
  |
 
  |-
 
  |-
  | rowspan="2"| Sky Light arrays
+
  | 1022
| Length
+
  | Wither breaks block
| rowspan="2"| Array
+
  |
  | VarInt
 
  | Length of the following array in bytes (always 2048)
 
 
  |-
 
  |-
  | Sky Light array
+
  | 1023
  | Array of 2048 bytes
+
  | Wither spawned
  | There is 1 array for each bit set to true in the sky light mask, starting with the lowest value.  Half a byte per light value.
+
  |
 
  |-
 
  |-
  | colspan="2"| Block Light array count
+
  | 1024
  | colspan="2"| VarInt
+
  | Wither shoots
  | Number of entries in the following array; should match the number of bits set in Block Light Mask
+
  |
 
  |-
 
  |-
  | rowspan="2"| Block Light arrays
+
  | 1025
| Length
+
  | Bat takes off
| rowspan="2"| Array
+
  |
  | VarInt
 
  | Length of the following array in bytes (always 2048)
 
 
  |-
 
  |-
  | Block Light array
+
  | 1026
  | Array of 2048 bytes
+
  | Zombie infects
  | There is 1 array for each bit set to true in the block light mask, starting with the lowest value.  Half a byte per light value.
+
  |
|}
 
 
 
A bit will never be set in both the block light mask and the empty block light mask, though it may be present in neither of them (if the block light does not need to be updated for the corresponding chunk section).  The same applies to the sky light mask and the empty sky light mask.
 
 
 
==== Login (play) ====
 
 
 
{{Need Info|Although the number of portal cooldown ticks is included in this packet, the whole portal usage process is still dictated entirely by the server. What kind of effect does this value have on the client, if any?}}
 
 
 
See [[Protocol Encryption]] for information on logging in.
 
 
 
{| class="wikitable"
 
! Packet ID
 
! State
 
! Bound To
 
! Field Name
 
! Field Type
 
! Notes
 
 
  |-
 
  |-
  | rowspan="21"| 0x29
+
  | 1027
| rowspan="21"| Play
+
  | Zombie villager converted
| rowspan="21"| Client
+
  |
| Entity ID
 
  | Int
 
  | The player's Entity ID (EID).
 
 
  |-
 
  |-
  | Is hardcore
+
  | 1028
  | Boolean
+
  | Ender dragon death
 
  |
 
  |
 
  |-
 
  |-
  | Dimension Count
+
  | 1029
  | VarInt
+
  | Anvil destroyed
  | Size of the following array.
+
  |
 
  |-
 
  |-
  | Dimension Names
+
  | 1030
  | Array of Identifier
+
  | Anvil used
  | Identifiers for all dimensions on the server.
+
  |
 
  |-
 
  |-
  | Max Players
+
  | 1031
  | VarInt
+
  | Anvil landed
  | Was once used by the client to draw the player list, but now is ignored.
+
  |
 
  |-
 
  |-
  | View Distance
+
  | 1032
  | VarInt
+
  | Portal travel
  | Render distance (2-32).
+
  |
 
  |-
 
  |-
  | Simulation Distance
+
  | 1033
  | VarInt
+
  | Chorus flower grown
  | The distance that the client will process specific things, such as entities.
+
  |
 
  |-
 
  |-
  | Reduced Debug Info
+
  | 1034
  | Boolean
+
  | Chorus flower died
  | If true, a Notchian client shows reduced information on the {{Minecraft Wiki|debug screen}}.  For servers in development, this should almost always be false.
+
  |
 
  |-
 
  |-
  | Enable respawn screen
+
  | 1035
  | Boolean
+
  | Brewing stand brewed
  | Set to false when the doImmediateRespawn gamerule is true.
+
|
 +
|-
 +
| 1038
 +
| End portal created in overworld
 +
  |
 
  |-
 
  |-
  | Do limited crafting
+
  | 1039
  | Boolean
+
  | Phantom bites
  | Whether players can only craft recipes they have already unlocked. Currently unused by the client.
+
  |
 +
|-
 +
| 1040
 +
| Zombie converts to drowned
 +
|
 +
|-
 +
| 1041
 +
| Husk converts to zombie by drowning
 +
|
 
  |-
 
  |-
  | Dimension Type
+
  | 1042
  | Identifier
+
  | Grindstone used
  | The type of dimension in the <code>minecraft:dimension_type</code> registry, defined by the [[Protocol#Registry_Data|Registry Data]] packet.
+
  |
 
  |-
 
  |-
  | Dimension Name
+
  | 1043
  | Identifier
+
  | Book page turned
  | Name of the dimension being spawned into.
+
  |
 
  |-
 
  |-
  | Hashed seed
+
  | 1044
  | Long
+
  | Smithing table used
  | First 8 bytes of the SHA-256 hash of the world's seed. Used client side for biome noise
+
  |
 
  |-
 
  |-
  | Game mode
+
  | 1045
  | Unsigned Byte
+
  | Pointed dripstone landing
  | 0: Survival, 1: Creative, 2: Adventure, 3: Spectator.
+
  |
 
  |-
 
  |-
  | Previous Game mode
+
  | 1046
  | Byte
+
  | Lava dripping on cauldron from dripstone
  | -1: Undefined (null), 0: Survival, 1: Creative, 2: Adventure, 3: Spectator. The previous game mode. Vanilla client uses this for the debug (F3 + N & F3 + F4) game mode switch. (More information needed)
+
  |
 
  |-
 
  |-
  | Is Debug
+
  | 1047
  | Boolean
+
  | Water dripping on cauldron from dripstone
  | True if the world is a {{Minecraft Wiki|debug mode}} world; debug mode worlds cannot be modified and have predefined blocks.
+
  |
 
  |-
 
  |-
  | Is Flat
+
  | 1048
  | Boolean
+
  | Skeleton converts to stray
  | True if the world is a {{Minecraft Wiki|superflat}} world; flat worlds have different void fog and a horizon at y=0 instead of y=63.
+
  |
 
  |-
 
  |-
  | Has death location
+
  | 1049
  | Boolean
+
  | Crafter successfully crafts item
  | If true, then the next two fields are present.
+
  |
 
  |-
 
  |-
  | Death dimension name
+
  | 1050
  | Optional Identifier
+
  | Crafter fails to craft item
  | Name of the dimension the player died in.
+
  |
 
  |-
 
  |-
| Death location
 
| Optional Position
 
| The location that the player died at.
 
 
  |-
 
  |-
| Portal cooldown
+
  ! colspan="3"| Particle
| VarInt
 
| The number of ticks until the player can use the portal again.
 
|}
 
 
 
==== Map Data ====
 
 
 
Updates a rectangular area on a {{Minecraft Wiki|map}} item.
 
 
 
{| class="wikitable"
 
! Packet ID
 
! State
 
! Bound To
 
  ! colspan="2"| Field Name
 
! colspan="2"| Field Type
 
! Notes
 
 
  |-
 
  |-
  | rowspan="17"| 0x2A
+
  | 1500
| rowspan="17"| Play
+
  | Composter composts
| rowspan="17"| Client
+
  |
  | colspan="2"| Map ID
 
| colspan="2"| VarInt
 
  | Map ID of the map being modified
 
 
  |-
 
  |-
  | colspan="2"| Scale
+
  | 1501
  | colspan="2"| Byte
+
  | Lava converts block (either water to stone, or removes existing blocks such as torches)
| From 0 for a fully zoomed-in map (1 block per pixel) to 4 for a fully zoomed-out map (16 blocks per pixel)
+
|
 
  |-
 
  |-
  | colspan="2"| Locked
+
  | 1502
  | colspan="2"| Boolean
+
  | Redstone torch burns out
  | True if the map has been locked in a cartography table
+
  |
 
  |-
 
  |-
  | colspan="2"| Has Icons
+
  | 1503
  | colspan="2"| Boolean
+
  | Ender eye placed
 
  |
 
  |
 
  |-
 
  |-
  | colspan="2"| Icon Count
+
  | 1504
  | colspan="2"| Optional VarInt
+
  | Fluid drips from dripstone
  | Number of elements in the following array. Only present if previous Boolean is true.
+
  |
 
  |-
 
  |-
  | rowspan="6"| Icon
+
  | 1505
| Type
+
  | Bonemeal particles
| rowspan="6"| Optional Array
+
  | How many particles to spawn.
  | VarInt Enum
 
  | See below
 
 
  |-
 
  |-
  | X
+
  | 2000
  | Byte
+
  | Spawns 10 smoke particles, e.g. from a fire
  | Map coordinates: -128 for furthest left, +127 for furthest right
+
  | Direction, see below.
 
  |-
 
  |-
  | Z
+
  | 2001
  | Byte
+
  | Block break + block break sound
  | Map coordinates: -128 for highest, +127 for lowest
+
  | Block state ID (see [[Chunk Format#Block state registry]]).
 
  |-
 
  |-
  | Direction
+
  | 2002
  | Byte
+
  | Splash potion. Particle effect + glass break sound.
  | 0-15
+
  | RGB color as an integer (e.g. 8364543 for #7FA1FF).
 
  |-
 
  |-
  | Has Display Name
+
  | 2003
  | Boolean
+
  | Eye of Ender entity break animation — particles and sound
 
  |
 
  |
 
  |-
 
  |-
  | Display Name
+
  | 2004
  | Optional [[Chat]]
+
  | Mob spawn particle effect: smoke + flames
  | Only present if previous Boolean is true
+
|
 +
|-
 +
| 2006
 +
| Dragon breath
 +
|
 +
|-
 +
| 2007
 +
| Instant splash potion. Particle effect + glass break sound.
 +
| RGB color as an integer (e.g. 8364543 for #7FA1FF).
 +
|-
 +
| 2008
 +
| Ender dragon destroys block
 +
|
 +
|-
 +
| 2009
 +
| Wet sponge vaporizes in nether
 +
  |
 
  |-
 
  |-
  | colspan="2"| Columns
+
  | 3000
  | colspan="2"| Unsigned Byte
+
  | End gateway spawn
  | Number of columns updated
+
  |
 
  |-
 
  |-
  | colspan="2"| Rows
+
  | 3001
  | colspan="2"| Optional Unsigned Byte
+
  | Enderdragon growl
  | Only if Columns is more than 0; number of rows updated
+
  |
 
  |-
 
  |-
  | colspan="2"| X
+
  | 3002
  | colspan="2"| Optional Byte
+
  | Electric spark
  | Only if Columns is more than 0; x offset of the westernmost column
+
  |
 
  |-
 
  |-
  | colspan="2"| Z
+
  | 3003
  | colspan="2"| Optional Byte
+
  | Copper apply wax
  | Only if Columns is more than 0; z offset of the northernmost row
+
  |
 
  |-
 
  |-
  | colspan="2"| Length
+
  | 3004
  | colspan="2"| Optional VarInt
+
  | Copper remove wax
  | Only if Columns is more than 0; length of the following array
+
  |
 
  |-
 
  |-
  | colspan="2"| Data
+
  | 3005
  | colspan="2"| Optional Array of Unsigned Byte
+
  | Copper scrape oxidation
  | Only if Columns is more than 0; see {{Minecraft Wiki|Map item format}}
+
  |
 
  |}
 
  |}
  
For icons, a direction of 0 is a vertical icon and increments by 22.5&deg; (360/16).
+
Smoke directions:
 
 
Types are based off of rows and columns in <code>map_icons.png</code>:
 
  
 
{| class="wikitable"
 
{| class="wikitable"
|-
+
  ! ID
  ! Icon type
+
  ! Direction
  ! Result
 
 
  |-
 
  |-
 
  | 0
 
  | 0
  | White arrow (players)
+
  | Down
 
  |-
 
  |-
 
  | 1
 
  | 1
  | Green arrow (item frames)
+
  | Up
 
  |-
 
  |-
 
  | 2
 
  | 2
  | Red arrow
+
  | North
 
  |-
 
  |-
 
  | 3
 
  | 3
  | Blue arrow
+
  | South
 
  |-
 
  |-
 
  | 4
 
  | 4
  | White cross
+
  | West
 
  |-
 
  |-
 
  | 5
 
  | 5
  | Red pointer
+
  | East
 +
|}
 +
 
 +
==== Particle ====
 +
 
 +
Displays the named particle
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 
  |-
 
  |-
  | 6
+
  | rowspan="11"| 0x29
  | White circle (off-map players)
+
| rowspan="11"| Play
 +
| rowspan="11"| Client
 +
| Long Distance
 +
| {{Type|Boolean}}
 +
  | If true, particle distance increases from 256 to 65536.
 
  |-
 
  |-
  | 7
+
  | X
  | Small white circle (far-off-map players)
+
  | {{Type|Double}}
 +
| X position of the particle.
 
  |-
 
  |-
  | 8
+
  | Y
  | Mansion
+
  | {{Type|Double}}
 +
| Y position of the particle.
 
  |-
 
  |-
  | 9
+
  | Z
  | Temple
+
  | {{Type|Double}}
 +
| Z position of the particle.
 
  |-
 
  |-
  | 10
+
  | Offset X
  | White Banner
+
  | {{Type|Float}}
 +
| This is added to the X position after being multiplied by <code>random.nextGaussian()</code>.
 
  |-
 
  |-
  | 11
+
  | Offset Y
  | Orange Banner
+
  | {{Type|Float}}
 +
| This is added to the Y position after being multiplied by <code>random.nextGaussian()</code>.
 
  |-
 
  |-
  | 12
+
  | Offset Z
  | Magenta Banner
+
  | {{Type|Float}}
 +
| This is added to the Z position after being multiplied by <code>random.nextGaussian()</code>.
 
  |-
 
  |-
  | 13
+
  | Max Speed
  | Light Blue Banner
+
| {{Type|Float}}
 +
  |
 
  |-
 
  |-
  | 14
+
  | Particle Count
  | Yellow Banner
+
  | {{Type|Int}}
 +
| The number of particles to create.
 
  |-
 
  |-
  | 15
+
  | Particle ID
  | Lime Banner
+
  | {{Type|VarInt}}
 +
| The particle ID listed in [[Particles]].
 
  |-
 
  |-
  | 16
+
  | Data
  | Pink Banner
+
  | Varies
  |-
+
  | Particle data as specified in [[Particles]].
| 17
 
| Gray Banner
 
|-
 
| 18
 
| Light Gray Banner
 
|-
 
| 19
 
| Cyan Banner
 
|-
 
| 20
 
| Purple Banner
 
|-
 
| 21
 
| Blue Banner
 
|-
 
| 22
 
| Brown Banner
 
|-
 
| 23
 
| Green Banner
 
|-
 
| 24
 
| Red Banner
 
|-
 
| 25
 
| Black Banner
 
|-
 
| 26
 
| Treasure marker
 
 
  |}
 
  |}
  
==== Merchant Offers ====
+
==== Update Light ====
  
The list of trades a villager NPC is offering.
+
Updates light levels for a chunk.  See {{Minecraft Wiki|Light}} for information on how lighting works in Minecraft.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 3,773: Line 4,029:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="16"| 0x2B
+
  | rowspan="12"| 0x2A
  | rowspan="16"| Play
+
  | rowspan="12"| Play
  | rowspan="16"| Client
+
  | rowspan="12"| Client
  | colspan="2"| Window ID
+
  | colspan="2"| Chunk X
  | colspan="2"| VarInt
+
  | colspan="2"| {{Type|VarInt}}
  | The ID of the window that is open; this is an int rather than a byte.
+
  | Chunk coordinate (block coordinate divided by 16, rounded down)
 
  |-
 
  |-
  | colspan="2"| Size
+
  | colspan="2"| Chunk Z
  | colspan="2"| VarInt
+
  | colspan="2"| {{Type|VarInt}}
  | The number of trades in the following array.
+
  | Chunk coordinate (block coordinate divided by 16, rounded down)
 
  |-
 
  |-
  | rowspan="10"| Trades
+
  | colspan="2"| Sky Light Mask
  | Input item 1
+
  | colspan="2"| {{Type|BitSet}}
| rowspan="10"| Array
+
  | BitSet containing bits for each section in the world + 2. Each set bit indicates that the corresponding 16×16×16 chunk section has data in the Sky Light array below. The least significant bit is for blocks 16 blocks to 1 block below the min world height (one section below the world), while the most significant bit covers blocks 1 to 16 blocks above the max world height (one section above the world).
  | [[Slot]]
 
  | The first item the player has to supply for this villager trade. The count of the item stack is the default "price" of this trade.
 
 
  |-
 
  |-
  | Output item
+
  | colspan="2"| Block Light Mask
  | [[Slot]]
+
  | colspan="2"| {{Type|BitSet}}
  | The item the player will receive from this villager trade.
+
  | BitSet containing bits for each section in the world + 2.  Each set bit indicates that the corresponding 16×16×16 chunk section has data in the Block Light array below.  The order of bits is the same as in Sky Light Mask.
 
  |-
 
  |-
  | Input item 2
+
  | colspan="2"| Empty Sky Light Mask
  | [[Slot]]
+
  | colspan="2"| {{Type|BitSet}}
  | The second item the player has to supply for this villager trade. May be an empty slot.
+
  | BitSet containing bits for each section in the world + 2.  Each set bit indicates that the corresponding 16×16×16 chunk section has all zeros for its Sky Light data. The order of bits is the same as in Sky Light Mask.
 
  |-
 
  |-
  | Trade disabled
+
  | colspan="2"| Empty Block Light Mask
  | Boolean
+
  | colspan="2"| {{Type|BitSet}}
  | True if the trade is disabled; false if the trade is enabled.
+
  | BitSet containing bits for each section in the world + 2.  Each set bit indicates that the corresponding 16×16×16 chunk section has all zeros for its Block Light data.  The order of bits is the same as in Sky Light Mask.
 
  |-
 
  |-
  | Number of trade uses
+
  | colspan="2"| Sky Light array count
  | Int
+
  | colspan="2"| {{Type|VarInt}}
  | Number of times the trade has been used so far. If equal to the maximum number of trades, the client will display a red X.
+
  | Number of entries in the following array; should match the number of bits set in Sky Light Mask
 
  |-
 
  |-
  | Maximum number of trade uses
+
  | rowspan="2"| Sky Light arrays
  | Int
+
| Length
  | Number of times this trade can be used before it's exhausted.
+
| rowspan="2"| {{Type|Array}}
 +
  | {{Type|VarInt}}
 +
  | Length of the following array in bytes (always 2048)
 
  |-
 
  |-
  | XP
+
  | Sky Light array
  | Int
+
  | {{Type|Byte Array}} (2048)
  | Amount of XP the villager will earn each time the trade is used.
+
  | There is 1 array for each bit set to true in the sky light mask, starting with the lowest value.  Half a byte per light value.
 
  |-
 
  |-
  | Special Price
+
  | colspan="2"| Block Light array count
  | Int
+
  | colspan="2"| {{Type|VarInt}}
  | Can be zero or negative. The number is added to the price when an item is discounted due to player reputation or other effects.
+
  | Number of entries in the following array; should match the number of bits set in Block Light Mask
 
  |-
 
  |-
  | Price Multiplier
+
  | rowspan="2"| Block Light arrays
  | Float
+
  | Length
  | Can be low (0.05) or high (0.2). Determines how much demand, player reputation, and temporary effects will adjust the price.
+
  | rowspan="2"| {{Type|Array}}
 +
| {{Type|VarInt}}
 +
| Length of the following array in bytes (always 2048)
 
  |-
 
  |-
  | Demand
+
  | Block Light array
  | Int
+
  | {{Type|Byte Array}} (2048)
| If positive, causes the price to increase. Negative values seem to be treated the same as zero.
+
  | There is 1 array for each bit set to true in the block light mask, starting with the lowest valueHalf a byte per light value.
|-
 
| colspan="2"| Villager level
 
| colspan="2"| VarInt
 
| Appears on the trade GUI; meaning comes from the translation key <code>merchant.level.</code> + level.
 
1: Novice, 2: Apprentice, 3: Journeyman, 4: Expert, 5: Master.
 
|-
 
| colspan="2"| Experience
 
| colspan="2"| VarInt
 
| Total experience for this villager (always 0 for the wandering trader).
 
|-
 
| colspan="2"| Is regular villager
 
| colspan="2"| Boolean
 
  | True if this is a regular villager; false for the wandering trader.  When false, hides the villager level and some other GUI elements.
 
  |-
 
| colspan="2"| Can restock
 
| colspan="2"| Boolean
 
| True for regular villagers and false for the wandering trader. If true, the "Villagers restock up to two times per day." message is displayed when hovering over disabled trades.
 
 
  |}
 
  |}
  
Modifiers can increase or decrease the number of items for the first input slot. The second input slot and the output slot never change the nubmer of items. The number of items may never be less than 1, and never more than the stack size. If special price and demand are both zero, only the default price is displayed. If either is non-zero, then the adjusted price is displayed next to the crossed-out default price. The adjusted prices is calculated as follows:
+
A bit will never be set in both the block light mask and the empty block light mask, though it may be present in neither of them (if the block light does not need to be updated for the corresponding chunk section). The same applies to the sky light mask and the empty sky light mask.
  
Adjusted price = default price + floor(default price x multiplier x demand) + special price
+
==== Login (play) ====
  
[[File:1.14-merchant-slots.png|thumb|The merchant UI, for reference]]
+
{{Need Info|Although the number of portal cooldown ticks is included in this packet, the whole portal usage process is still dictated entirely by the server. What kind of effect does this value have on the client, if any?}}
{{-}}
 
  
==== Update Entity Position ====
+
See [[Protocol Encryption]] for information on logging in.
 
 
This packet is sent by the server when an entity moves less then 8 blocks; if an entity moves more than 8 blocks [[#Teleport Entity|Teleport Entity]] should be sent instead.
 
 
 
This packet allows at most 8 blocks movement in any direction, because short range is from -32768 to 32767. And <code>32768 / (128 * 32)</code> = 8.
 
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 3,865: Line 4,101:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="5"| 0x2C
+
  | rowspan="22"| ''protocol:''<br/><code>0x2B</code><br/><br/>''resource:''<br/><code>login</code>
  | rowspan="5"| Play
+
  | rowspan="22"| Play
  | rowspan="5"| Client
+
  | rowspan="22"| Client
 
  | Entity ID
 
  | Entity ID
  | VarInt
+
  | {{Type|Int}}
 +
| The player's Entity ID (EID).
 +
|-
 +
| Is hardcore
 +
| {{Type|Boolean}}
 
  |
 
  |
 
  |-
 
  |-
  | Delta X
+
  | Dimension Count
  | Short
+
  | {{Type|VarInt}}
  | Change in X position as <code>(currentX * 32 - prevX * 32) * 128</code>.
+
  | Size of the following array.
 
  |-
 
  |-
  | Delta Y
+
  | Dimension Names
  | Short
+
  | {{Type|Array}} of {{Type|Identifier}}
  | Change in Y position as <code>(currentY * 32 - prevY * 32) * 128</code>.
+
  | Identifiers for all dimensions on the server.
 
  |-
 
  |-
  | Delta Z
+
  | Max Players
  | Short
+
  | {{Type|VarInt}}
  | Change in Z position as <code>(currentZ * 32 - prevZ * 32) * 128</code>.
+
  | Was once used by the client to draw the player list, but now is ignored.
 
  |-
 
  |-
  | On Ground
+
  | View Distance
  | Boolean
+
  | {{Type|VarInt}}
|
+
  | Render distance (2-32).
  |}
 
 
 
==== Update Entity Position and Rotation ====
 
 
 
This packet is sent by the server when an entity rotates and moves. Since a short range is limited from -32768 to 32767, and movement is offset of fixed-point numbers, this packet allows at most 8 blocks movement in any direction. (<code>-32768 / (32 * 128) == -8</code>)
 
 
 
{| class="wikitable"
 
! Packet ID
 
! State
 
! Bound To
 
! Field Name
 
! Field Type
 
! Notes
 
 
  |-
 
  |-
  | rowspan="7"| 0x2D
+
  | Simulation Distance
| rowspan="7"| Play
+
  | {{Type|VarInt}}
  | rowspan="7"| Client
+
  | The distance that the client will process specific things, such as entities.
| Entity ID
 
| VarInt
 
  |
 
 
  |-
 
  |-
  | Delta X
+
  | Reduced Debug Info
  | Short
+
  | {{Type|Boolean}}
  | Change in X position as <code>(currentX * 32 - prevX * 32) * 128</code>.
+
  | If true, a Notchian client shows reduced information on the {{Minecraft Wiki|debug screen}}.  For servers in development, this should almost always be false.
 
  |-
 
  |-
  | Delta Y
+
  | Enable respawn screen
  | Short
+
  | {{Type|Boolean}}
  | Change in Y position as <code>(currentY * 32 - prevY * 32) * 128</code>.
+
  | Set to false when the doImmediateRespawn gamerule is true.
 
  |-
 
  |-
  | Delta Z
+
  | Do limited crafting
  | Short
+
  | {{Type|Boolean}}
  | Change in Z position as <code>(currentZ * 32 - prevZ * 32) * 128</code>.
+
  | Whether players can only craft recipes they have already unlocked. Currently unused by the client.
 
  |-
 
  |-
  | Yaw
+
  | Dimension Type
  | Angle
+
  | {{Type|VarInt}}
  | New angle, not a delta.
+
  | The ID of the type of dimension in the <code>minecraft:dimension_type</code> registry, defined by the Registry Data packet.
 
  |-
 
  |-
  | Pitch
+
  | Dimension Name
  | Angle
+
  | {{Type|Identifier}}
  | New angle, not a delta.
+
| Name of the dimension being spawned into.
 +
|-
 +
| Hashed seed
 +
| {{Type|Long}}
 +
| First 8 bytes of the SHA-256 hash of the world's seed. Used client side for biome noise
 +
|-
 +
| Game mode
 +
| {{Type|Unsigned Byte}}
 +
| 0: Survival, 1: Creative, 2: Adventure, 3: Spectator.
 +
  |-
 +
| Previous Game mode
 +
| {{Type|Byte}}
 +
| -1: Undefined (null), 0: Survival, 1: Creative, 2: Adventure, 3: Spectator. The previous game mode. Vanilla client uses this for the debug (F3 + N & F3 + F4) game mode switch. (More information needed)
 +
|-
 +
| Is Debug
 +
| {{Type|Boolean}}
 +
| True if the world is a {{Minecraft Wiki|debug mode}} world; debug mode worlds cannot be modified and have predefined blocks.
 +
|-
 +
| Is Flat
 +
| {{Type|Boolean}}
 +
| True if the world is a {{Minecraft Wiki|superflat}} world; flat worlds have different void fog and a horizon at y=0 instead of y=63.
 +
|-
 +
| Has death location
 +
| {{Type|Boolean}}
 +
| If true, then the next two fields are present.
 +
|-
 +
| Death dimension name
 +
| {{Type|Optional}} {{Type|Identifier}}
 +
| Name of the dimension the player died in.
 +
|-
 +
| Death location
 +
| {{Type|Optional}} {{Type|Position}}
 +
| The location that the player died at.
 +
|-
 +
| Portal cooldown
 +
| {{Type|VarInt}}
 +
| The number of ticks until the player can use the portal again.
 
  |-
 
  |-
  | On Ground
+
  | Enforces Secure Chat
  | Boolean
+
  | {{Type|Boolean}}
 
  |
 
  |
 
  |}
 
  |}
  
==== Update Entity Rotation ====
+
==== Map Data ====
  
This packet is sent by the server when an entity rotates.
+
Updates a rectangular area on a {{Minecraft Wiki|map}} item.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 3,941: Line 4,201:
 
  ! State
 
  ! State
 
  ! Bound To
 
  ! Bound To
  ! Field Name
+
  ! colspan="2"| Field Name
  ! Field Type
+
  ! colspan="2"| Field Type
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="4"| 0x2E
+
  | rowspan="17"| 0x2C
  | rowspan="4"| Play
+
  | rowspan="17"| Play
  | rowspan="4"| Client
+
  | rowspan="17"| Client
  | Entity ID
+
  | colspan="2"| Map ID
  | VarInt
+
  | colspan="2"| {{Type|VarInt}}
  |
+
  | Map ID of the map being modified
 +
|-
 +
| colspan="2"| Scale
 +
| colspan="2"| {{Type|Byte}}
 +
| From 0 for a fully zoomed-in map (1 block per pixel) to 4 for a fully zoomed-out map (16 blocks per pixel)
 
  |-
 
  |-
  | Yaw
+
  | colspan="2"| Locked
  | Angle
+
  | colspan="2"| {{Type|Boolean}}
  | New angle, not a delta.
+
  | True if the map has been locked in a cartography table
 
  |-
 
  |-
  | Pitch
+
  | colspan="2"| Has Icons
  | Angle
+
| colspan="2"| {{Type|Boolean}}
  | New angle, not a delta.
+
|
 +
|-
 +
| colspan="2"| Icon Count
 +
| colspan="2"| {{Type|Optional}} {{Type|VarInt}}
 +
| Number of elements in the following array. Only present if previous Boolean is true.
 +
|-
 +
| rowspan="6"| Icon
 +
| Type
 +
| rowspan="6"| {{Type|Optional}} {{Type|Array}}
 +
| {{Type|VarInt}} {{Type|Enum}}
 +
| See below
 +
|-
 +
| X
 +
  | {{Type|Byte}}
 +
  | Map coordinates: -128 for furthest left, +127 for furthest right
 +
|-
 +
| Z
 +
| {{Type|Byte}}
 +
| Map coordinates: -128 for highest, +127 for lowest
 +
|-
 +
| Direction
 +
| {{Type|Byte}}
 +
| 0-15
 
  |-
 
  |-
  | On Ground
+
  | Has Display Name
  | Boolean
+
  | {{Type|Boolean}}
 
  |
 
  |
 +
|-
 +
| Display Name
 +
| {{Type|Optional}} {{Type|Text Component}}
 +
| Only present if previous Boolean is true
 +
|-
 +
| rowspan="6"| Color Patch
 +
| Columns
 +
| colspan="2"| {{Type|Unsigned Byte}}
 +
| Number of columns updated
 +
|-
 +
| Rows
 +
| colspan="2"| {{Type|Optional}} {{Type|Unsigned Byte}}
 +
| Only if Columns is more than 0; number of rows updated
 +
|-
 +
| X
 +
| colspan="2"| {{Type|Optional}} {{Type|Unsigned Byte}}
 +
| Only if Columns is more than 0; x offset of the westernmost column
 +
|-
 +
| Z
 +
| colspan="2"| {{Type|Optional}} {{Type|Unsigned Byte}}
 +
| Only if Columns is more than 0; z offset of the northernmost row
 +
|-
 +
| Length
 +
| colspan="2"| {{Type|Optional}} {{Type|VarInt}}
 +
| Only if Columns is more than 0; length of the following array
 +
|-
 +
| Data
 +
| colspan="2"| {{Type|Optional}} {{Type|Array}} of {{Type|Unsigned Byte}}
 +
| Only if Columns is more than 0; see {{Minecraft Wiki|Map item format}}
 
  |}
 
  |}
  
==== Move Vehicle ====
+
For icons, a direction of 0 is a vertical icon and increments by 22.5&deg; (360/16).
  
Note that all fields use absolute positioning and do not allow for relative positioning.
+
Types are based off of rows and columns in <code>map_icons.png</code>:
  
 
{| class="wikitable"
 
{| class="wikitable"
! Packet ID
 
! State
 
! Bound To
 
! Field Name
 
! Field Type
 
! Notes
 
 
  |-
 
  |-
  | rowspan="5"| 0x2F
+
  ! Icon type
  | rowspan="5"| Play
+
  ! Result
| rowspan="5"| Client
 
| X
 
| Double
 
| Absolute position (X coordinate).
 
 
  |-
 
  |-
  | Y
+
  | 0
  | Double
+
  | White arrow (players)
| Absolute position (Y coordinate).
 
 
  |-
 
  |-
  | Z
+
  | 1
  | Double
+
  | Green arrow (item frames)
| Absolute position (Z coordinate).
 
 
  |-
 
  |-
  | Yaw
+
  | 2
  | Float
+
  | Red arrow
| Absolute rotation on the vertical axis, in degrees.
 
 
  |-
 
  |-
  | Pitch
+
  | 3
  | Float
+
  | Blue arrow
| Absolute rotation on the horizontal axis, in degrees.
 
|}
 
 
 
==== Open Book ====
 
 
 
Sent when a player right clicks with a signed book. This tells the client to open the book GUI.
 
 
 
{| class="wikitable"
 
! Packet ID
 
! State
 
! Bound To
 
! Field Name
 
! Field Type
 
! Notes
 
 
  |-
 
  |-
  | 0x30
+
  | 4
  | Play
+
  | White cross
| Client
 
| Hand
 
| VarInt Enum
 
| 0: Main hand, 1: Off hand .
 
|}
 
 
 
==== Open Screen ====
 
 
 
This is sent to the client when it should open an inventory, such as a chest, workbench, furnace, or other container. This message is not sent anywhere for clients opening their own inventory. Resending this packet with already existing window id, will update the window title and window type without closing the window.
 
For horses, use [[#Open Horse Screen|Open Horse Screen]].
 
 
 
{| class="wikitable"
 
! Packet ID
 
! State
 
! Bound To
 
! Field Name
 
! Field Type
 
! Notes
 
 
  |-
 
  |-
  | rowspan="3"| 0x31
+
  | 5
| rowspan="3"| Play
+
  | Red pointer
| rowspan="3"| Client
 
| Window ID
 
| VarInt
 
  | A unique id number for the window to be displayed. Notchian server implementation is a counter, starting at 1.
 
 
  |-
 
  |-
  | Window Type
+
  | 6
  | VarInt
+
  | White circle (off-map players)
  | The window type to use for display. Contained in the <code>minecraft:menu</code> registry; see [[Inventory]] for the different values.
+
  |-
 +
| 7
 +
| Small white circle (far-off-map players)
 +
|-
 +
| 8
 +
| Mansion
 
  |-
 
  |-
  | Window Title
+
  | 9
  | [[Chat]]
+
  | Monument
| The title of the window.
 
|}
 
 
 
==== Open Sign Editor ====
 
 
 
Sent when the client has placed a sign and is allowed to send [[#Update Sign|Update Sign]].  There must already be a sign at the given location (which the client does not do automatically) - send a [[#Block Update|Block Update]] first.
 
 
 
{| class="wikitable"
 
! Packet ID
 
! State
 
! Bound To
 
! Field Name
 
! Field Type
 
! Notes
 
 
  |-
 
  |-
  | rowspan="2" | 0x32
+
  | 10
| rowspan="2" | Play
+
  | White Banner
| rowspan="2" | Client
 
| Location
 
| Position
 
  |
 
 
  |-
 
  |-
  | Is Front Text
+
  | 11
  | Boolean
+
  | Orange Banner
| Whether the opened editor is for the front or on the back of the sign
 
|}
 
 
 
==== Ping (play) ====
 
 
 
Packet is not used by the Notchian server. When sent to the client, client responds with a [[#Pong (play)|Pong]] packet with the same id.
 
 
 
{| class="wikitable"
 
! Packet ID
 
! State
 
! Bound To
 
! Field Name
 
! Field Type
 
! Notes
 
 
  |-
 
  |-
  | 0x33
+
  | 12
  | Play
+
  | Magenta Banner
  | Client
+
  |-
  | ID
+
  | 13
  | Int
+
  | Light Blue Banner
  |
+
  |-
  |}
+
  | 14
 
+
| Yellow Banner
==== Ping Response (play) ====
+
|-
 
+
| 15
{| class="wikitable"
+
| Lime Banner
  ! Packet ID
+
|-
  ! State
+
| 16
  ! Bound To
+
| Pink Banner
  ! Field Name
+
  |-
  ! Field Type
+
  | 17
  ! Notes
+
  | Gray Banner
 +
  |-
 +
  | 18
 +
  | Light Gray Banner
 +
|-
 +
| 19
 +
| Cyan Banner
 +
|-
 +
| 20
 +
| Purple Banner
 +
|-
 +
| 21
 +
| Blue Banner
 +
|-
 +
| 22
 +
| Brown Banner
 +
|-
 +
| 23
 +
| Green Banner
 +
|-
 +
| 24
 +
| Red Banner
 +
|-
 +
| 25
 +
| Black Banner
 
  |-
 
  |-
  | 0x34
+
  | 26
  | Play
+
  | Treasure marker
| Client
 
| Payload
 
| Long
 
| Should be the same as sent by the client.
 
 
  |}
 
  |}
  
==== Place Ghost Recipe ====
+
==== Merchant Offers ====
  
Response to the serverbound packet ([[#Place Recipe|Place Recipe]]), with the same recipe ID. Appears to be used to notify the UI.
+
The list of trades a villager NPC is offering.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 4,120: Line 4,379:
 
  ! State
 
  ! State
 
  ! Bound To
 
  ! Bound To
  ! Field Name
+
  ! colspan="2"| Field Name
  ! Field Type
+
  ! colspan="2"| Field Type
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="2"| 0x35
+
  | rowspan="16"| 0x2D
  | rowspan="2"| Play
+
  | rowspan="16"| Play
  | rowspan="2"| Client
+
  | rowspan="16"| Client
  | Window ID
+
  | colspan="2"| Window ID
  | Byte
+
  | colspan="2"| {{Type|VarInt}}
  |
+
  | The ID of the window that is open; this is an int rather than a byte.
 
  |-
 
  |-
  | Recipe
+
  | colspan="2"| Size
  | Identifier
+
  | colspan="2"| {{Type|VarInt}}
| A recipe ID.
+
  | The number of trades in the following array.
  |}
 
 
 
==== Player Abilities ====
 
 
 
The latter 2 floats are used to indicate the flying speed and field of view respectively, while the first byte is used to determine the value of 4 booleans.
 
 
 
{| class="wikitable"
 
! Packet ID
 
! State
 
! Bound To
 
! Field Name
 
! Field Type
 
! Notes
 
 
  |-
 
  |-
  | rowspan="3"| 0x36
+
  | rowspan="10"| Trades
  | rowspan="3"| Play
+
  | Input item 1
  | rowspan="3"| Client
+
  | rowspan="10"| {{Type|Array}}
| Flags
+
  | Trade Item
  | Byte
+
  | See below. The first item the player has to supply for this villager trade. The count of the item stack is the default "price" of this trade.
  | Bit field, see below.
 
 
  |-
 
  |-
  | Flying Speed
+
  | Output item
  | Float
+
  | {{Type|Slot}}
  | 0.05 by default.
+
  | The item the player will receive from this villager trade.
 
  |-
 
  |-
  | Field of View Modifier
+
  | Input item 2
  | Float
+
  | {{Type|Optional}} Trade Item
  | Modifies the field of view, like a speed potion. A Notchian server will use the same value as the movement speed sent in the [[#Update Attributes|Update Attributes]] packet, which defaults to 0.1 for players.
+
  | The second item the player has to supply for this villager trade. May be an empty slot.
|}
 
 
 
About the flags:
 
 
 
{| class="wikitable"
 
 
  |-
 
  |-
  ! Field
+
  | Trade disabled
  ! Bit
+
  | {{Type|Boolean}}
 +
| True if the trade is disabled; false if the trade is enabled.
 
  |-
 
  |-
  | Invulnerable
+
  | Number of trade uses
  | 0x01
+
  | {{Type|Int}}
 +
| Number of times the trade has been used so far. If equal to the maximum number of trades, the client will display a red X.
 
  |-
 
  |-
  | Flying
+
  | Maximum number of trade uses
  | 0x02
+
  | {{Type|Int}}
 +
| Number of times this trade can be used before it's exhausted.
 +
|-
 +
| XP
 +
| {{Type|Int}}
 +
| Amount of XP the villager will earn each time the trade is used.
 +
|-
 +
| Special Price
 +
| {{Type|Int}}
 +
| Can be zero or negative. The number is added to the price when an item is discounted due to player reputation or other effects.
 +
|-
 +
| Price Multiplier
 +
| {{Type|Float}}
 +
| Can be low (0.05) or high (0.2). Determines how much demand, player reputation, and temporary effects will adjust the price.
 +
|-
 +
| Demand
 +
| {{Type|Int}}
 +
| If positive, causes the price to increase. Negative values seem to be treated the same as zero.
 +
|-
 +
| colspan="2"| Villager level
 +
| colspan="2"| {{Type|VarInt}}
 +
| Appears on the trade GUI; meaning comes from the translation key <code>merchant.level.</code> + level.
 +
1: Novice, 2: Apprentice, 3: Journeyman, 4: Expert, 5: Master.
 +
|-
 +
| colspan="2"| Experience
 +
| colspan="2"| {{Type|VarInt}}
 +
| Total experience for this villager (always 0 for the wandering trader).
 +
|-
 +
| colspan="2"| Is regular villager
 +
| colspan="2"| {{Type|Boolean}}
 +
| True if this is a regular villager; false for the wandering trader.  When false, hides the villager level and some other GUI elements.
 +
|-
 +
| colspan="2"| Can restock
 +
| colspan="2"| {{Type|Boolean}}
 +
| True for regular villagers and false for the wandering trader. If true, the "Villagers restock up to two times per day." message is displayed when hovering over disabled trades.
 +
|}
 +
 
 +
Trade Item:
 +
{| class="wikitable"
 +
! Field Name
 +
! colspan="3"| Field Type
 +
! Meaning
 +
|-
 +
| Item ID
 +
| colspan="3"|{{Type|VarInt}}
 +
| The {{Minecraft Wiki|Java Edition data values#Blocks|item ID}}. Item IDs are distinct from block IDs; see [[Data Generators]] for more information.
 +
|-
 +
| Item Count
 +
| colspan="3"|{{Type|VarInt}}
 +
| The item count.
 +
|-
 +
| Size
 +
| colspan="3"| {{Type|VarInt}}
 +
| The number of components in the following array.
 +
|-
 +
| rowspan="2" | Components
 +
| Component type
 +
| rowspan="2" | {{Type|Array}}
 +
| {{Type|VarInt}} {{Type|Enum}}
 +
| colspan="1" | The type of component. See [[Slot_Data#Structured_components|Structured components]] for more detail.
 
  |-
 
  |-
  | Allow Flying
+
  | Component data
  | 0x04
+
  | Varies
 +
| colspan="1"| The component-dependent data. See [[Slot_Data#Structured_components|Structured components]] for more detail.
 
  |-
 
  |-
| Creative Mode (Instant Break)
 
| 0x08
 
 
  |}
 
  |}
  
==== Player Chat Message ====
+
Modifiers can increase or decrease the number of items for the first input slot. The second input slot and the output slot never change the number of items. The number of items may never be less than 1, and never more than the stack size. If special price and demand are both zero, only the default price is displayed. If either is non-zero, then the adjusted price is displayed next to the crossed-out default price. The adjusted prices is calculated as follows:
 +
 
 +
Adjusted price = default price + floor(default price x multiplier x demand) + special price
 +
 
 +
[[File:1.14-merchant-slots.png|thumb|The merchant UI, for reference]]
 +
{{-}}
  
Sends the client a chat message from a player.
+
==== Update Entity Position ====
  
Currently a lot is unknown about this packet, blank descriptions are for those that are unknown
+
This packet is sent by the server when an entity moves a small distance. The change in position is represented as a [[#Fixed-point numbers|fixed-point number]] with 12 fraction bits and 4 integer bits. As such, the maximum movement distance along each axis is 8 blocks in the negative direction, or 7.999755859375 blocks in the positive direction. If the movement exceeds these limits, [[#Teleport Entity|Teleport Entity]] should be sent instead.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 4,194: Line 4,499:
 
  ! State
 
  ! State
 
  ! Bound To
 
  ! Bound To
  ! Sector
+
  ! Field Name
! colspan="2"| Field Name
 
 
  ! Field Type
 
  ! Field Type
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="18"| 0x37
+
  | rowspan="5"| ''protocol:''<br/><code>0x2E</code><br/><br/>''resource:''<br/><code>move_entity_pos</code>
  | rowspan="18"| Play
+
  | rowspan="5"| Play
  | rowspan="18"| Client
+
  | rowspan="5"| Client
  | rowspan="4"| Header
+
  | Entity ID
  | colspan="2"| Sender
+
  | {{Type|VarInt}}
| UUID
+
  |
  | Used by the Notchian client for the disableChat launch option. Setting both longs to 0 will always display the message regardless of the setting.
 
 
  |-
 
  |-
  | colspan="2"| Index
+
  | Delta X
  | VarInt
+
  | {{Type|Short}}
  |  
+
  | Change in X position as <code>currentX * 4096 - prevX * 4096</code>.
 
  |-
 
  |-
  | colspan="2"| Message Signature Present
+
  | Delta Y
  | Boolean
+
  | {{Type|Short}}
  | States if a message signature is present
+
  | Change in Y position as <code>currentY * 4096 - prevY * 4096</code>.
 
  |-
 
  |-
  | colspan="2"| Message Signature bytes
+
  | Delta Z
  | Optional Byte Array (256)
+
  | {{Type|Short}}
  | Only present if <code>Message Signature Present</code> is true. Cryptography, the signature consists of the Sender UUID, Session UUID from the [[#Player Session|Player Session]] packet, Index, Salt, Timestamp in epoch seconds, the length of the original chat content, the original content itself, the length of Previous Messages, and all of the Previous message signatures. These values are hashed with [https://en.wikipedia.org/wiki/SHA-2 SHA-256] and signed using the [https://en.wikipedia.org/wiki/RSA_(cryptosystem) RSA] cryptosystem. Modifying any of these values in the packet will cause this signature to fail. This buffer is always 256 bytes long and it is not length-prefixed.
+
  | Change in Z position as <code>currentZ * 4096 - prevZ * 4096</code>.
 
  |-
 
  |-
  | rowspan="3"| Body
+
  | On Ground
  | colspan="2"| Message
+
  | {{Type|Boolean}}
  | String (256)
+
  |
  | Raw (optionally) signed sent message content.
+
  |}
This is used as the <code>content</code> parameter when formatting the message on the client.
+
 
 +
==== Update Entity Position and Rotation ====
 +
 
 +
This packet is sent by the server when an entity rotates and moves. See [[#Update Entity Position]] for how the position is encoded.
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 
  |-
 
  |-
  | colspan="2"| Timestamp
+
  | rowspan="7"| ''protocol:''<br/><code>0x2F</code><br/><br/>''resource:''<br/><code>move_entity_pos_rot</code>
  | Long
+
  | rowspan="7"| Play
  | Represents the time the message was signed as milliseconds since the [https://en.wikipedia.org/wiki/Unix_time epoch], used to check if the message was received within 2 minutes of it being sent.
+
| rowspan="7"| Client
 +
| Entity ID
 +
| {{Type|VarInt}}
 +
  |
 
  |-
 
  |-
  | colspan="2"| Salt
+
  | Delta X
  | Long
+
  | {{Type|Short}}
  | Cryptography, used for validating the message signature.  
+
  | Change in X position as <code>currentX * 4096 - prevX * 4096</code>.
 
  |-
 
  |-
  | rowspan="3"| Previous Messages
+
  | Delta Y
  | colspan="2"| Total Previous Messages
+
  | {{Type|Short}}
| VarInt
+
  | Change in Y position as <code>currentY * 4096 - prevY * 4096</code>.
  | The maximum length is 20 in Notchian client.
 
|
 
 
  |-
 
  |-
  | rowspan="2"| Array (20)
+
  | Delta Z
  | Message ID
+
  | {{Type|Short}}
| VarInt
+
  | Change in Z position as <code>currentZ * 4096 - prevZ * 4096</code>.
  | The message Id + 1, used for validating message signature. The next field is present only when value of this field is equal to 0.
 
 
  |-
 
  |-
  | Signature
+
  | Yaw
  | Optional Byte Array (256)
+
  | {{Type|Angle}}
  | The previous message's signature. Contains the same type of data as <code>Message Signature bytes</code> (256 bytes) above. Not length-prefxied.
+
  | New angle, not a delta.
 
  |-
 
  |-
  | rowspan="4"| Other
+
  | Pitch
  | colspan="2"| Unsigned Content Present
+
  | {{Type|Angle}}
| Boolean
+
  | New angle, not a delta.
  | True if the next field is present
 
 
  |-
 
  |-
  | colspan="2"| Unsigned Content
+
  | On Ground
| Optional Chat
+
  | {{Type|Boolean}}
|
+
  |
|-
 
| colspan="2"| Filter Type
 
| Enum VarInt
 
| If the message has been filtered
 
|-
 
| colspan="2"| Filter Type Bits
 
| Optional BitSet
 
| Only present if the Filter Type is Partially Filtered. Specifies the indexes at which characters in the original message string should be replaced with the <code>#</code> symbol (i.e. filtered) by the Notchian client
 
  |-
 
| rowspan="4"| Chat Formatting
 
| colspan="2"| Chat Type
 
| VarInt
 
| The type of chat in the <code>minecraft:chat_type</code> registry, defined by the [[Protocol#Registry_Data|Registry Data]] packet.
 
|-
 
| colspan="2"| Sender Name
 
| Chat
 
| The name of the one sending the message, usually the sender's display name.
 
This is used as the <code>sender</code> parameter when formatting the message on the client.
 
|-
 
| colspan="2"| Has Target Name
 
| Boolean
 
  | True if target name is present.
 
|-
 
| colspan="2"| Target Name
 
| Optional Chat
 
| The name of the one receiving the message, usually the receiver's display name. Only present if previous boolean is true.
 
This is used as the <code>target</code> parameter when formatting the message on the client.
 
 
  |}
 
  |}
[[File:MinecraftChat.drawio4.png|thumb|Player Chat Handling Logic]]
 
  
Filter Types:
+
==== Update Entity Rotation ====
  
The filter type mask should NOT be specified unless partially filtered is selected
+
This packet is sent by the server when an entity rotates.
 
 
{| class="wikitable"
 
! ID
 
! Name
 
! Description
 
|-
 
| 0
 
| PASS_THROUGH
 
| Message is not filtered at all
 
|-
 
| 1
 
| FULLY_FILTERED
 
| Message is fully filtered
 
|-
 
| 2
 
| PARTIALLY_FILTERED
 
| Only some characters in the message are filtered
 
|}
 
 
 
==== End Combat ====
 
 
 
Unused by the Notchian client.  This data was once used for twitch.tv metadata circa 1.8.
 
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 4,320: Line 4,583:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="1"| 0x38
+
  | rowspan="4"| ''protocol:''<br/><code>0x30</code><br/><br/>''resource:''<br/><code>move_entity_rot</code>
  | rowspan="1"| Play
+
  | rowspan="4"| Play
  | rowspan="1"| Client
+
  | rowspan="4"| Client
  | Duration
+
  | Entity ID
  | VarInt
+
  | {{Type|VarInt}}
  | Length of the combat in ticks.
+
|
 +
  |-
 +
| Yaw
 +
| {{Type|Angle}}
 +
| New angle, not a delta.
 +
|-
 +
| Pitch
 +
| {{Type|Angle}}
 +
| New angle, not a delta.
 +
|-
 +
| On Ground
 +
| {{Type|Boolean}}
 +
|
 
  |}
 
  |}
  
==== Enter Combat ====
+
==== Move Vehicle ====
  
Unused by the Notchian client.  This data was once used for twitch.tv metadata circa 1.8.
+
Note that all fields use absolute positioning and do not allow for relative positioning.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 4,340: Line 4,615:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="1"| 0x39
+
  | rowspan="5"| 0x31
  | rowspan="1"| Play
+
  | rowspan="5"| Play
  | rowspan="1"| Client
+
  | rowspan="5"| Client
  | colspan="3"| ''no fields''
+
  | X
 +
| {{Type|Double}}
 +
| Absolute position (X coordinate).
 +
|-
 +
| Y
 +
| {{Type|Double}}
 +
| Absolute position (Y coordinate).
 +
|-
 +
| Z
 +
| {{Type|Double}}
 +
| Absolute position (Z coordinate).
 +
|-
 +
| Yaw
 +
| {{Type|Float}}
 +
| Absolute rotation on the vertical axis, in degrees.
 +
|-
 +
| Pitch
 +
| {{Type|Float}}
 +
| Absolute rotation on the horizontal axis, in degrees.
 
  |}
 
  |}
  
==== Combat Death ====
+
==== Open Book ====
  
Used to send a respawn screen.
+
Sent when a player right clicks with a signed book. This tells the client to open the book GUI.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 4,358: Line 4,651:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="2"| 0x3A
+
  | 0x32
  | rowspan="2"| Play
+
  | Play
  | rowspan="2"| Client
+
  | Client
  | Player ID
+
  | Hand
  | VarInt
+
  | {{Type|VarInt}} {{Type|Enum}}
| Entity ID of the player that died (should match the client's entity ID).
+
  | 0: Main hand, 1: Off hand .
|-
 
| Message
 
| [[Chat]]
 
  | The death message.
 
 
  |}
 
  |}
  
==== Player Info Remove ====
+
==== Open Screen ====
 +
 
 +
This is sent to the client when it should open an inventory, such as a chest, workbench, furnace, or other container. Resending this packet with already existing window id, will update the window title and window type without closing the window.
 +
 
 +
This message is not sent to clients opening their own inventory, nor do clients inform the server in any way when doing so. From the server's perspective, the inventory is always "open" whenever no other windows are.
  
Used by the server to remove players from the player list.
+
For horses, use [[#Open Horse Screen|Open Horse Screen]].
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 4,378: Line 4,671:
 
  ! State
 
  ! State
 
  ! Bound To
 
  ! Bound To
  ! colspan="2"| Field Name
+
  ! Field Name
 
  ! Field Type
 
  ! Field Type
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="2"| 0x3B
+
  | rowspan="3"| 0x33
  | rowspan="2"| Play
+
  | rowspan="3"| Play
  | rowspan="2"| Client
+
  | rowspan="3"| Client
  | colspan="2"| Number of Players
+
  | Window ID
  | VarInt
+
| {{Type|VarInt}}
  | Number of elements in the following array.
+
| An identifier for the window to be displayed. Notchian server implementation is a counter, starting at 1. There can only be one window at a time; this is only used to ignore outdated packets targeting already-closed windows. Note also that the Window ID field in most other packets is only a single byte, and indeed, the Notchian server wraps around after 100.
 +
|-
 +
| Window Type
 +
  | {{Type|VarInt}}
 +
  | The window type to use for display. Contained in the <code>minecraft:menu</code> registry; see [[Inventory]] for the different values.
 
  |-
 
  |-
  | Player
+
  | Window Title
  | Player Id
+
  | {{Type|Text Component}}
| Array of UUID
+
  | The title of the window.
  | UUIDs of players to remove.
 
 
  |}
 
  |}
  
==== Player Info Update ====
+
==== Open Sign Editor ====
 +
 
 +
Sent when the client has placed a sign and is allowed to send [[#Update Sign|Update Sign]].  There must already be a sign at the given location (which the client does not do automatically) - send a [[#Block Update|Block Update]] first.
  
Sent by the server to update the user list (<tab> in the client).
 
 
{| class="wikitable"
 
{| class="wikitable"
 
  ! Packet ID
 
  ! Packet ID
 
  ! State
 
  ! State
 
  ! Bound To
 
  ! Bound To
  ! colspan="2"| Field Name
+
  ! Field Name
  ! colspan="2"| Field Type
+
  ! Field Type
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="4"| 0x3C
+
  | rowspan="2" | 0x34
  | rowspan="4"| Play
+
  | rowspan="2" | Play
  | rowspan="4"| Client
+
  | rowspan="2" | Client
  | colspan="2"| Actions
+
  | Location
  | colspan="2"| [[#Definitions:byte|Byte]]
+
  | {{Type|Position}}
  | Determines what actions are present.
+
  |
 
  |-
 
  |-
  | colspan="2"| Number Of Players
+
  | Is Front Text
  | colspan="2"| [[#Definitions:varint|VarInt]]
+
  | {{Type|Boolean}}
  | Number of elements in the following array.
+
  | Whether the opened editor is for the front or on the back of the sign
|-
 
| rowspan="2" | Players
 
| UUID
 
| rowspan="2" | Array
 
| [[#Definitions:uuid|UUID]]
 
| The player UUID
 
|-
 
| Player Actions
 
| Array of [[#player-info:player-actions|Player&nbsp;Actions]]
 
| The length of this array is determined by the number of [[#player-info:player-actions|Player Actions]] that give a non-zero value when applying its mask to the actions flag. For example given the decimal number 5, binary 00000101. The masks 0x01 and 0x04 would return a non-zero value, meaning the Player Actions array would include two actions: Add Player and Update Game Mode.
 
 
  |}
 
  |}
+
 
 +
==== Ping (play) ====
 +
 
 +
Packet is not used by the Notchian server. When sent to the client, client responds with a [[#Pong (play)|Pong]] packet with the same id.
  
 
{| class="wikitable"
 
{| class="wikitable"
  |+ id="player-info:player-actions" | Player Actions
+
  ! Packet ID
  ! Action
+
  ! State
  ! Mask
+
  ! Bound To
  ! colspan="2" | Field Name
+
  ! Field Name
  ! colspan="2" | Type
+
  ! Field Type
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="6" | Add Player
+
  | 0x35
| rowspan="6" | 0x01
+
  | Play
| colspan="2" | Name
+
  | Client
| colspan="2" | [[#Definitions:string|String (16)]]
+
  | ID
|-
+
  | {{Type|Int}}
  | colspan="2" | Number Of Properties
 
  | colspan="2" | [[#Definitions:varint|VarInt]]
 
  | Number of elements in the following array.
 
|-
 
| rowspan="4" | Property
 
| Name
 
| rowspan="4"| Array
 
  | [[#Definitions:string|String (32767)]]
 
 
  |
 
  |
 +
|}
 +
 +
==== Ping Response (play) ====
 +
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 
  |-
 
  |-
  | Value
+
  | 0x36
  | [[#Definitions:string|String (32767)]]
+
  | Play
  |
+
| Client
 +
| Payload
 +
| {{Type|Long}}
 +
| Should be the same as sent by the client.
 +
|}
 +
 
 +
==== Place Ghost Recipe ====
 +
 
 +
Response to the serverbound packet ([[#Place Recipe|Place Recipe]]), with the same recipe ID. Appears to be used to notify the UI.
 +
 
 +
{| class="wikitable"
 +
  ! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 
  |-
 
  |-
  | Is Signed
+
  | rowspan="2"| 0x37
  | [[#Definitions:boolean|Boolean]]
+
| rowspan="2"| Play
 +
| rowspan="2"| Client
 +
| Window ID
 +
  | {{Type|Byte}}
 
  |
 
  |
 
  |-
 
  |-
  | Signature
+
  | Recipe
  | Optional [[#Definitions:string|String (32767)]]
+
  | {{Type|Identifier}}
  | Only if Is Signed is true.
+
  | A recipe ID.
|-
 
| rowspan="7" | Initialize Chat
 
| rowspan="7" | 0x02
 
| colspan="2" | Has Signature Data
 
| colspan="2" | [[#Definitions:boolean|Boolean]]
 
|-
 
| colspan="2" | Chat session ID
 
| colspan="2" | [[#Definitions:uuid|UUID]]
 
| Only sent if Has Signature Data is true.
 
|-
 
| colspan="2" | Public key expiry time
 
| colspan="2" | [[#Definitions:long|Long]]
 
| Key expiry time, as a UNIX timestamp in milliseconds. Only sent if Has Signature Data is true.
 
|-
 
| colspan="2" | Encoded public key size
 
| colspan="2" | [[#Definitions:varint|VarInt]]
 
| Size of the following array. Only sent if Has Signature Data is true. Maximum length is 512 bytes.
 
|-
 
| colspan="2" | Encoded public key
 
| colspan="2" | [[#Definitions:byte|Byte]] Array (512)
 
| The player's public key, in bytes. Only sent if Has Signature Data is true.
 
|-
 
| colspan="2" | Public key signature size
 
| colspan="2" | [[#Definitions:varint|VarInt]]
 
| Size of the following array. Only sent if Has Signature Data is true. Maximum length is 4096 bytes.
 
|-
 
| colspan="2" | Public key signature
 
| colspan="2" | [[#Definitions:byte|Byte]] Array (4096)
 
| The public key's digital signature. Only sent if Has Signature Data is true.
 
|-
 
| Update Game Mode
 
| 0x04
 
| colspan="2" | Game Mode
 
| colspan="2" | [[#Definitions:varint|VarInt]]
 
|-
 
| Update Listed
 
| 0x08
 
| colspan="2" | Listed
 
| colspan="2" | [[#Definitions:boolean|Boolean]]
 
| Whether the player should be listed on the player list.
 
|-
 
| Update Latency
 
| 0x10
 
| colspan="2" | Ping
 
| colspan="2" | [[#Definitions:varint|VarInt]]
 
| Measured in milliseconds.
 
|-
 
| rowspan="2" | Update Display Name
 
| rowspan="2" | 0x20
 
| colspan="2" | Has Display Name
 
| colspan="2" | [[#Definitions:boolean|Boolean]]
 
|-
 
| colspan="2" | Display Name
 
| colspan="2" | Optional [[#Definitions:chat|Chat]]
 
| Only sent if Has Display Name is true.
 
 
  |}
 
  |}
  
The Property field looks as in the response of [[Mojang API#UUID -> Profile + Skin/Cape]], except of course using the protocol format instead of JSON. That is, each player will usually have one property with Name “textures” and Value being a base64-encoded JSON string as documented at [[Mojang API#UUID -> Profile + Skin/Cape]]. An empty properties array is also acceptable, and will cause clients to display the player with one of the two default skins depending on UUID.
+
==== Player Abilities (clientbound) ====
  
Ping values correspond with icons in the following way:
+
The latter 2 floats are used to indicate the flying speed and field of view respectively, while the first byte is used to determine the value of 4 booleans.
* A ping that negative (i.e. not known to the server yet) will result in the no connection icon.
 
* A ping under 150 milliseconds will result in 5 bars
 
* A ping under 300 milliseconds will result in 4 bars
 
* A ping under 600 milliseconds will result in 3 bars
 
* A ping under 1000 milliseconds (1 second) will result in 2 bars
 
* A ping greater than or equal to 1 second will result in 1 bar.
 
 
 
==== Look At ====
 
 
 
Used to rotate the client player to face the given location or entity (for <code>/teleport [<targets>] <x> <y> <z> facing</code>).
 
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 4,542: Line 4,789:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="8"| 0x3D
+
  | rowspan="3"| 0x38
  | rowspan="8"| Play
+
  | rowspan="3"| Play
  | rowspan="8"| Client
+
  | rowspan="3"| Client
 +
| Flags
 +
| {{Type|Byte}}
 +
| Bit field, see below.
 
  |-
 
  |-
  | Feet/eyes
+
  | Flying Speed
  | VarInt Enum
+
  | {{Type|Float}}
  | Values are feet=0, eyes=1. If set to eyes, aims using the head position; otherwise aims using the feet position.
+
  | 0.05 by default.
 
  |-
 
  |-
  | Target x
+
  | Field of View Modifier
  | Double
+
  | {{Type|Float}}
  | x coordinate of the point to face towards.
+
  | Modifies the field of view, like a speed potion. A Notchian server will use the same value as the movement speed sent in the [[#Update Attributes|Update Attributes]] packet, which defaults to 0.1 for players.
 +
|}
 +
 
 +
About the flags:
 +
 
 +
{| class="wikitable"
 
  |-
 
  |-
  | Target y
+
  ! Field
  | Double
+
  ! Bit
| y coordinate of the point to face towards.
 
 
  |-
 
  |-
  | Target z
+
  | Invulnerable
  | Double
+
  | 0x01
| z coordinate of the point to face towards.
 
 
  |-
 
  |-
  | Is entity
+
  | Flying
  | Boolean
+
  | 0x02
| If true, additional information about an entity is provided.
 
 
  |-
 
  |-
  | Entity ID
+
  | Allow Flying
  | Optional VarInt
+
  | 0x04
| Only if is entity is true &mdash; the entity to face towards.
 
 
  |-
 
  |-
  | Entity feet/eyes
+
  | Creative Mode (Instant Break)
  | Optional VarInt Enum
+
  | 0x08
| Whether to look at the entity's eyes or feet.  Same values and meanings as before, just for the entity's head/feet.
 
 
  |}
 
  |}
  
If the entity given by entity ID cannot be found, this packet should be treated as if is entity was false.
+
==== Player Chat Message ====
  
==== Synchronize Player Position ====
+
{{Main|Chat}}
  
Updates the player's position on the server. This packet will also close the “Downloading Terrain” screen when joining/respawning.
+
Sends the client a chat message from a player.  
  
If the distance between the last known position of the player on the server and the new position set by this packet is greater than 100 meters, the client will be kicked for “You moved too quickly :( (Hacking?)”.
+
Currently a lot is unknown about this packet, blank descriptions are for those that are unknown
 
 
Also if the fixed-point number of X or Z is set greater than <code>3.2E7D</code> the client will be kicked for “Illegal position”.
 
 
 
Yaw is measured in degrees, and does not follow classical trigonometry rules. The unit circle of yaw on the XZ-plane starts at (0, 1) and turns counterclockwise, with 90 at (-1, 0), 180 at (0, -1) and 270 at (1, 0). Additionally, yaw is not clamped to between 0 and 360 degrees; any number is valid, including negative numbers and numbers greater than 360.
 
 
 
Pitch is measured in degrees, where 0 is looking straight ahead, -90 is looking straight up, and 90 is looking straight down.
 
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 4,593: Line 4,837:
 
  ! State
 
  ! State
 
  ! Bound To
 
  ! Bound To
  ! Field Name
+
  ! Sector
 +
! colspan="2"| Field Name
 
  ! Field Type
 
  ! Field Type
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="7"| 0x3E
+
  | rowspan="18"| ''protocol:''<br/><code>0x39</code><br/><br/>''resource:''<br/><code>player_chat</code>
  | rowspan="7"| Play
+
  | rowspan="18"| Play
  | rowspan="7"| Client
+
  | rowspan="18"| Client
  | X
+
  | rowspan="4"| Header
  | [[#Definitions:double|Double]]
+
  | colspan="2"| Sender
  | Absolute or relative position, depending on Flags.
+
| {{Type|UUID}}
 +
  | Used by the Notchian client for the disableChat launch option. Setting both longs to 0 will always display the message regardless of the setting.
 
  |-
 
  |-
  | Y
+
  | colspan="2"| Index
  | [[#Definitions:double|Double]]
+
  | {{Type|VarInt}}
  | Absolute or relative position, depending on Flags.
+
  |  
 
  |-
 
  |-
  | Z
+
  | colspan="2"| Message Signature Present
  | [[#Definitions:double|Double]]
+
  | {{Type|Boolean}}
  | Absolute or relative position, depending on Flags.
+
  | States if a message signature is present
 
  |-
 
  |-
  | Yaw
+
  | colspan="2"| Message Signature bytes
  | [[#Definitions:float|Float]]
+
  | {{Type|Optional}} {{Type|Byte Array}} (256)
| Absolute or relative rotation on the X axis, in degrees.
+
| Only present if <code>Message Signature Present</code> is true. Cryptography, the signature consists of the Sender UUID, Session UUID from the [[#Player Session|Player Session]] packet, Index, Salt, Timestamp in epoch seconds, the length of the original chat content, the original content itself, the length of Previous Messages, and all of the Previous message signatures. These values are hashed with [https://en.wikipedia.org/wiki/SHA-2 SHA-256] and signed using the [https://en.wikipedia.org/wiki/RSA_(cryptosystem) RSA] cryptosystem. Modifying any of these values in the packet will cause this signature to fail. This buffer is always 256 bytes long and it is not length-prefixed.
 
  |-
 
  |-
  | Pitch
+
  | rowspan="3"| Body
  | [[#Definitions:float|Float]]
+
| colspan="2"| Message
  | Absolute or relative rotation on the Y axis, in degrees.
+
  | {{Type|String}} (256)
 +
  | Raw (optionally) signed sent message content.
 +
This is used as the <code>content</code> parameter when formatting the message on the client.
 
  |-
 
  |-
  | Flags
+
  | colspan="2"| Timestamp
  | [[#Definitions:byte|Byte]]
+
  | {{Type|Long}}
  | Reference the Flags table below. When the value of the this byte masked is zero the field is absolute, otherwise relative.
+
  | Represents the time the message was signed as milliseconds since the [https://en.wikipedia.org/wiki/Unix_time epoch], used to check if the message was received within 2 minutes of it being sent.
 
  |-
 
  |-
  | Teleport ID
+
  | colspan="2"| Salt
  | [[#Definitions:varint|VarInt]]
+
  | {{Type|Long}}
  | Client should confirm this packet with [[#Confirm Teleportation|Confirm Teleportation]] containing the same Teleport ID.
+
  | Cryptography, used for validating the message signature.  
|}
 
 
 
{| class="wikitable"
 
|+ Flags
 
 
  |-
 
  |-
  ! Field
+
  | rowspan="3"| Previous Messages
  ! Hex Mask
+
  | colspan="2"| Total Previous Messages
 +
| {{Type|VarInt}}
 +
| The maximum length is 20 in Notchian client.
 +
|
 
  |-
 
  |-
  | X
+
  | rowspan="2"| {{Type|Array}} (20)
  | 0x01
+
| Message ID
 +
| {{Type|VarInt}}
 +
  | The message Id + 1, used for validating message signature. The next field is present only when value of this field is equal to 0.
 
  |-
 
  |-
  | Y
+
  | Signature
  | 0x02
+
  | {{Type|Optional}} {{Type|Byte Array}} (256)
 +
| The previous message's signature. Contains the same type of data as <code>Message Signature bytes</code> (256 bytes) above. Not length-prefxied.
 
  |-
 
  |-
  | Z
+
  | rowspan="4"| Other
  | 0x04
+
| colspan="2"| Unsigned Content Present
 +
| {{Type|Boolean}}
 +
  | True if the next field is present
 
  |-
 
  |-
  | Y_ROT
+
  | colspan="2"| Unsigned Content
  | 0x08
+
| {{Type|Optional}} {{Type|Text Component}}
 +
  |  
 
  |-
 
  |-
  | X_ROT
+
  | colspan="2"| Filter Type
  | 0x10
+
| {{Type|VarInt}} {{Type|Enum}}
 +
| If the message has been filtered
 +
|-
 +
| colspan="2"| Filter Type Bits
 +
  | {{Type|Optional}} {{Type|BitSet}}
 +
| Only present if the Filter Type is Partially Filtered. Specifies the indexes at which characters in the original message string should be replaced with the <code>#</code> symbol (i.e. filtered) by the Notchian client
 +
|-
 +
| rowspan="4"| Chat Formatting
 +
| colspan="2"| Chat Type
 +
| {{Type|VarInt}}
 +
| The type of chat in the <code>minecraft:chat_type</code> registry, defined by the [[Protocol#Registry_Data|Registry Data]] packet. This should not be 0, meaning it is likely index+1
 +
|-
 +
| colspan="2"| Sender Name
 +
| {{Type|Text Component}}
 +
| The name of the one sending the message, usually the sender's display name.
 +
This is used as the <code>sender</code> parameter when formatting the message on the client.
 +
|-
 +
| colspan="2"| Has Target Name
 +
| {{Type|Boolean}}
 +
| True if target name is present.
 +
|-
 +
| colspan="2"| Target Name
 +
| {{Type|Optional}} {{Type|Text Component}}
 +
| The name of the one receiving the message, usually the receiver's display name. Only present if previous boolean is true.
 +
This is used as the <code>target</code> parameter when formatting the message on the client.
 
  |}
 
  |}
 +
[[File:MinecraftChat.drawio4.png|thumb|Player Chat Handling Logic]]
 +
 +
Filter Types:
 +
 +
The filter type mask should NOT be specified unless partially filtered is selected
  
==== Update Recipe Book ====
+
{| class="wikitable"
 +
! ID
 +
! Name
 +
! Description
 +
|-
 +
| 0
 +
| PASS_THROUGH
 +
| Message is not filtered at all
 +
|-
 +
| 1
 +
| FULLY_FILTERED
 +
| Message is fully filtered
 +
|-
 +
| 2
 +
| PARTIALLY_FILTERED
 +
| Only some characters in the message are filtered
 +
|}
 +
 
 +
==== End Combat ====
 +
 
 +
Unused by the Notchian client.  This data was once used for twitch.tv metadata circa 1.8.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 4,661: Line 4,963:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="14"| 0x3F
+
  | rowspan="1"| 0x3A
  | rowspan="14"| Play
+
  | rowspan="1"| Play
  | rowspan="14"| Client
+
  | rowspan="1"| Client
  |-
+
  | Duration
  | Action
+
  | {{Type|VarInt}}
| VarInt
+
  | Length of the combat in ticks.
| 0: init, 1: add, 2: remove.
+
  |}
|-
+
 
| Crafting Recipe Book Open
+
==== Enter Combat ====
| Boolean
 
| If true, then the crafting recipe book will be open when the player opens its inventory.
 
|-
 
| Crafting Recipe Book Filter Active
 
| Boolean
 
| If true, then the filtering option is active when the players opens its inventory.
 
|-
 
| Smelting Recipe Book Open
 
| Boolean
 
| If true, then the smelting recipe book will be open when the player opens its inventory.
 
|-
 
| Smelting Recipe Book Filter Active
 
| Boolean
 
| If true, then the filtering option is active when the players opens its inventory.
 
|-
 
| Blast Furnace Recipe Book Open
 
| Boolean
 
| If true, then the blast furnace recipe book will be open when the player opens its inventory.
 
|-
 
| Blast Furnace Recipe Book Filter Active
 
| Boolean
 
| If true, then the filtering option is active when the players opens its inventory.
 
|-
 
| Smoker Recipe Book Open
 
| Boolean
 
| If true, then the smoker recipe book will be open when the player opens its inventory.
 
|-
 
| Smoker Recipe Book Filter Active
 
| Boolean
 
| If true, then the filtering option is active when the players opens its inventory.
 
|-
 
| Array size 1
 
| VarInt
 
  | Number of elements in the following array.
 
|-
 
| Recipe IDs
 
| Array of Identifier
 
|
 
|-
 
| Array size 2
 
| Optional VarInt
 
| Number of elements in the following array, only present if mode is 0 (init).
 
|-
 
| Recipe IDs
 
| Optional Array of Identifier
 
| Only present if mode is 0 (init)
 
  |}
 
Action:
 
* 0 (init) = All the recipes in list 1 will be tagged as displayed, and all the recipes in list 2 will be added to the recipe book. Recipes that aren't tagged will be shown in the notification.
 
* 1 (add) = All the recipes in the list are added to the recipe book and their icons will be shown in the notification.
 
* 2 (remove) = Remove all the recipes in the list. This allows them to be re-displayed when they are re-added.
 
  
==== Remove Entities ====
+
Unused by the Notchian client.  This data was once used for twitch.tv metadata circa 1.8.
 
 
Sent by the server when an entity is to be destroyed on the client.
 
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 4,734: Line 4,983:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="2"| 0x40
+
  | rowspan="1"| 0x3B
  | rowspan="2"| Play
+
  | rowspan="1"| Play
  | rowspan="2"| Client
+
  | rowspan="1"| Client
  | Count
+
  | colspan="3"| ''no fields''
| VarInt
 
| Number of elements in the following array.
 
|-
 
| Entity IDs
 
| Array of VarInt
 
| The list of entities to destroy.
 
 
  |}
 
  |}
  
==== Remove Entity Effect ====
+
==== Combat Death ====
 +
 
 +
Used to send a respawn screen.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 4,756: Line 5,001:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="2"| 0x41
+
  | rowspan="2"| ''protocol:''<br/><code>0x3C</code><br/><br/>''resource:''<br/><code>player_combat_kill</code>
 
  | rowspan="2"| Play
 
  | rowspan="2"| Play
 
  | rowspan="2"| Client
 
  | rowspan="2"| Client
  | Entity ID
+
  | Player ID
  | VarInt
+
  | {{Type|VarInt}}
  |
+
  | Entity ID of the player that died (should match the client's entity ID).
 
  |-
 
  |-
  | Effect ID
+
  | Message
  | VarInt
+
  | {{Type|Text Component}}
| See {{Minecraft Wiki|Status effect#Effect list|this table}}.
+
| The death message.
 
  |}
 
  |}
  
==== Resource Pack (play) ====
+
==== Player Info Remove ====
 +
 
 +
Used by the server to remove players from the player list.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 4,774: Line 5,021:
 
  ! State
 
  ! State
 
  ! Bound To
 
  ! Bound To
  ! Field Name
+
  ! colspan="2"| Field Name
 
  ! Field Type
 
  ! Field Type
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="5"| 0x42
+
  | rowspan="2"| 0x3D
  | rowspan="5"| Play
+
  | rowspan="2"| Play
  | rowspan="5"| Client
+
  | rowspan="2"| Client
  | URL
+
  | colspan="2"| Number of Players
  | String (32767)
+
  | {{Type|VarInt}}
  | The URL to the resource pack.
+
  | Number of elements in the following array.
 
  |-
 
  |-
  | Hash
+
  | Player
  | String (40)
+
  | Player Id
  | A 40 character hexadecimal and lowercase [[wikipedia:SHA-1|SHA-1]] hash of the resource pack file.<br />If it's not a 40 character hexadecimal string, the client will not use it for hash verification and likely waste bandwidth — but it will still treat it as a unique id
+
  | {{Type|Array}} of {{Type|UUID}}
|-
+
  | UUIDs of players to remove.
  | Forced
 
| Boolean
 
| The notchian client will be forced to use the resource pack from the server. If they decline they will be kicked from the server.
 
|-
 
| Has Prompt Message
 
| Boolean
 
| <code>true</code> If the next field will be sent <code>false</code> otherwise. When <code>false</code>, this is the end of the packet
 
|-
 
| Prompt Message
 
| Optional [[Chat]]
 
| This is shown in the prompt making the client accept or decline the resource pack.
 
 
  |}
 
  |}
  
==== Respawn ====
+
==== Player Info Update ====
 
 
{{Need Info|Although the number of portal cooldown ticks is included in this packet, the whole portal usage process is still dictated entirely by the server. What kind of effect does this value have on the client, if any?}}
 
 
 
To change the player's dimension (overworld/nether/end), send them a respawn packet with the appropriate dimension, followed by prechunks/chunks for the new dimension, and finally a position and look packet. You do not need to unload chunks, the client will do it automatically.
 
  
 +
Sent by the server to update the user list (<tab> in the client).
 
{| class="wikitable"
 
{| class="wikitable"
 
  ! Packet ID
 
  ! Packet ID
 
  ! State
 
  ! State
 
  ! Bound To
 
  ! Bound To
  ! Field Name
+
  ! colspan="2"| Field Name
  ! Field Type
+
  ! colspan="2"| Field Type
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="12"| 0x43
+
  | rowspan="4"| 0x3E
  | rowspan="12"| Play
+
  | rowspan="4"| Play
  | rowspan="12"| Client
+
  | rowspan="4"| Client
  | Dimension Type
+
  | colspan="2"| Actions
  | Identifier
+
  | colspan="2"| {{Type|Byte}}
  | The type of dimension in the <code>minecraft:dimension_type</code> registry, defined by the [[Protocol#Registry_Data|Registry Data]] packet.
+
  | Determines what actions are present.
 
  |-
 
  |-
  | Dimension Name
+
  | colspan="2"| Number Of Players
  | Identifier
+
  | colspan="2"| {{Type|VarInt}}
  | Name of the dimension being spawned into.
+
  | Number of elements in the following array.
 
  |-
 
  |-
  | Hashed seed
+
  | rowspan="2" | Players
  | Long
+
| UUID
  | First 8 bytes of the SHA-256 hash of the world's seed. Used client side for biome noise
+
| rowspan="2" | {{Type|Array}}
 +
| {{Type|UUID}}
 +
| The player UUID
 +
|-
 +
| Player Actions
 +
  | {{Type|Array}} of [[#player-info:player-actions|Player&nbsp;Actions]]
 +
  | The length of this array is determined by the number of [[#player-info:player-actions|Player Actions]] that give a non-zero value when applying its mask to the actions flag. For example given the decimal number 5, binary 00000101. The masks 0x01 and 0x04 would return a non-zero value, meaning the Player Actions array would include two actions: Add Player and Update Game Mode.
 +
|}
 +
 +
 
 +
{| class="wikitable"
 +
|+ id="player-info:player-actions" | Player Actions
 +
! Action
 +
! Mask
 +
! colspan="2" | Field Name
 +
! colspan="2" | Type
 +
! Notes
 
  |-
 
  |-
  | Game mode
+
  | rowspan="6" | Add Player
  | Unsigned Byte
+
  | rowspan="6" | 0x01
  | 0: Survival, 1: Creative, 2: Adventure, 3: Spectator.
+
  | colspan="2" | Name
 +
| colspan="2" | {{Type|String}} (16)
 
  |-
 
  |-
  | Previous Game mode
+
  | colspan="2" | Number Of Properties
  | Byte
+
  | colspan="2" | {{Type|VarInt}}
  | -1: Undefined (null), 0: Survival, 1: Creative, 2: Adventure, 3: Spectator. The previous game mode. Vanilla client uses this for the debug (F3 + N & F3 + F4) game mode switch. (More information needed)
+
  | Number of elements in the following array.
 
  |-
 
  |-
  | Is Debug
+
  | rowspan="4" | Property
  | Boolean
+
  | Name
  | True if the world is a {{Minecraft Wiki|debug mode}} world; debug mode worlds cannot be modified and have predefined blocks.
+
  | rowspan="4"| {{Type|Array}}
 +
| {{Type|String}} (32767)
 +
|
 
  |-
 
  |-
  | Is Flat
+
  | Value
  | Boolean
+
  | {{Type|String}} (32767)
| True if the world is a {{Minecraft Wiki|superflat}} world; flat worlds have different void fog and a horizon at y=0 instead of y=63.
+
|
 
  |-
 
  |-
  | Has death location
+
  | Is Signed
  | Boolean
+
  | {{Type|Boolean}}
  | If true, then the next two fields are present.
+
  |
 
  |-
 
  |-
  | Death dimension Name
+
  | Signature
  | Optional Identifier
+
  | {{Type|Optional}} {{Type|String}} (32767)
  | Name of the dimension the player died in.
+
  | Only if Is Signed is true.
 
  |-
 
  |-
  | Death location
+
  | rowspan="7" | Initialize Chat
  | Optional Position
+
| rowspan="7" | 0x02
  | The location that the player died at.
+
  | colspan="2" | Has Signature Data
 +
  | colspan="2" | {{Type|Boolean}}
 
  |-
 
  |-
  | Portal cooldown
+
  | colspan="2" | Chat session ID
  | VarInt
+
  | colspan="2" | {{Type|UUID}}
  | The number of ticks until the player can use the portal again.
+
  | Only sent if Has Signature Data is true.
 
  |-
 
  |-
  | Data kept
+
  | colspan="2" | Public key expiry time
  | Byte
+
| colspan="2" | {{Type|Long}}
  | Bit mask. 0x01: Keep attributes, 0x02: Keep metadata. Tells which data should be kept on the client side once the player has respawned.
+
| Key expiry time, as a UNIX timestamp in milliseconds. Only sent if Has Signature Data is true.
In the Notchian implementation, this is context dependent:
+
|-
* normal respawns (after death) keep no data;
+
| colspan="2" | Encoded public key size
* exiting the end poem/credits keeps the attributes;
+
| colspan="2" | {{Type|VarInt}}
* other dimension changes (portals or teleports) keep all data.
+
| Size of the following array. Only sent if Has Signature Data is true. Maximum length is 512 bytes.
 +
  |-
 +
| colspan="2" | Encoded public key
 +
| colspan="2" | {{Type|Byte Array}} (512)
 +
  | The player's public key, in bytes. Only sent if Has Signature Data is true.
 +
|-
 +
| colspan="2" | Public key signature size
 +
| colspan="2" | {{Type|VarInt}}
 +
| Size of the following array. Only sent if Has Signature Data is true. Maximum length is 4096 bytes.
 +
|-
 +
| colspan="2" | Public key signature
 +
| colspan="2" | {{Type|Byte Array}} (4096)
 +
| The public key's digital signature. Only sent if Has Signature Data is true.
 +
|-
 +
| Update Game Mode
 +
| 0x04
 +
| colspan="2" | Game Mode
 +
| colspan="2" | {{Type|VarInt}}
 +
|-
 +
| Update Listed
 +
| 0x08
 +
| colspan="2" | Listed
 +
| colspan="2" | {{Type|Boolean}}
 +
| Whether the player should be listed on the player list.
 +
|-
 +
| Update Latency
 +
| 0x10
 +
| colspan="2" | Ping
 +
| colspan="2" | {{Type|VarInt}}
 +
| Measured in milliseconds.
 +
|-
 +
| rowspan="2" | Update Display Name
 +
| rowspan="2" | 0x20
 +
| colspan="2" | Has Display Name
 +
| colspan="2" | {{Type|Boolean}}
 +
|-
 +
| colspan="2" | Display Name
 +
| colspan="2" | {{Type|Optional}} {{Type|Text Component}}
 +
| Only sent if Has Display Name is true.
 
  |}
 
  |}
  
{{Warning2|Avoid changing player's dimension to same dimension they were already in unless they are dead. If you change the dimension to one they are already in, weird bugs can occur, such as the player being unable to attack other players in new world (until they die and respawn).
+
The properties included in this packet are the same as in [[#Login Success|Login Success]], for the current player.
  
Before 1.16, if you must respawn a player in the same dimension without killing them, send two respawn packets, one to a different world and then another to the world you want. You do not need to complete the first respawn; it only matters that you send two packets.}}
+
Ping values correspond with icons in the following way:
 +
* A ping that negative (i.e. not known to the server yet) will result in the no connection icon.
 +
* A ping under 150 milliseconds will result in 5 bars
 +
* A ping under 300 milliseconds will result in 4 bars
 +
* A ping under 600 milliseconds will result in 3 bars
 +
* A ping under 1000 milliseconds (1 second) will result in 2 bars
 +
* A ping greater than or equal to 1 second will result in 1 bar.
  
==== Set Head Rotation ====
+
==== Look At ====
  
Changes the direction an entity's head is facing.
+
Used to rotate the client player to face the given location or entity (for <code>/teleport [<targets>] <x> <y> <z> facing</code>).
 
 
While sending the Entity Look packet changes the vertical rotation of the head, sending this packet appears to be necessary to rotate the head horizontally.
 
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 4,890: Line 5,185:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="2"| 0x44
+
  | rowspan="8"| 0x3F
  | rowspan="2"| Play
+
  | rowspan="8"| Play
  | rowspan="2"| Client
+
  | rowspan="8"| Client
| Entity ID
 
| VarInt
 
|
 
 
  |-
 
  |-
  | Head Yaw
+
  | Feet/eyes
  | Angle
+
  | {{Type|VarInt}} {{Type|Enum}}
  | New angle, not a delta.
+
| Values are feet=0, eyes=1.  If set to eyes, aims using the head position; otherwise aims using the feet position.
 +
|-
 +
| Target x
 +
| {{Type|Double}}
 +
| x coordinate of the point to face towards.
 +
|-
 +
| Target y
 +
| {{Type|Double}}
 +
| y coordinate of the point to face towards.
 +
|-
 +
| Target z
 +
| {{Type|Double}}
 +
| z coordinate of the point to face towards.
 +
|-
 +
| Is entity
 +
| {{Type|Boolean}}
 +
| If true, additional information about an entity is provided.
 +
|-
 +
| Entity ID
 +
| {{Type|Optional}} {{Type|VarInt}}
 +
| Only if is entity is true &mdash; the entity to face towards.
 +
|-
 +
| Entity feet/eyes
 +
  | {{Type|Optional}} {{Type|VarInt}} {{Type|Enum}}
 +
| Whether to look at the entity's eyes or feet.  Same values and meanings as before, just for the entity's head/feet.
 
  |}
 
  |}
  
==== Update Section Blocks ====
+
If the entity given by entity ID cannot be found, this packet should be treated as if is entity was false.
 +
 
 +
==== Synchronize Player Position ====
 +
 
 +
Teleports the client, e.g. during login, when using an ender pearl, in response to invalid move packets, etc.
 +
 
 +
Due to latency, the server may receive outdated movement packets sent before the client was aware of the teleport. To account for this, the server ignores all movement packets from the client until a [[#Confirm Teleportation|Confirm Teleportation]] packet with an ID matching the one sent in the teleport packet is received.
  
Fired whenever 2 or more blocks are changed within the same chunk on the same tick.
+
Yaw is measured in degrees, and does not follow classical trigonometry rules. The unit circle of yaw on the XZ-plane starts at (0, 1) and turns counterclockwise, with 90 at (-1, 0), 180 at (0, -1) and 270 at (1, 0). Additionally, yaw is not clamped to between 0 and 360 degrees; any number is valid, including negative numbers and numbers greater than 360 (see [https://bugs.mojang.com/browse/MC-90097 MC-90097]).
  
{{Warning|Changing blocks in chunks not loaded by the client is unsafe (see note on [[#Block Update|Block Update]]).}}
+
Pitch is measured in degrees, where 0 is looking straight ahead, -90 is looking straight up, and 90 is looking straight down.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 4,916: Line 5,238:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="3"| 0x45
+
  | rowspan="7"| ''protocol:''<br/><code>0x40</code><br/><br/>''resource:''<br/><code>player_position</code>
  | rowspan="3"| Play
+
  | rowspan="7"| Play
  | rowspan="3"| Client
+
  | rowspan="7"| Client
  | Chunk section position
+
  | X
  | Long
+
| {{Type|Double}}
  | Chunk section coordinate (encoded chunk x and z with each 22 bits, and section y with 20 bits, from left to right).
+
| Absolute or relative position, depending on Flags.
 +
  |-
 +
| Y
 +
| {{Type|Double}}
 +
  | Absolute or relative position, depending on Flags.
 +
|-
 +
| Z
 +
| {{Type|Double}}
 +
| Absolute or relative position, depending on Flags.
 
  |-
 
  |-
  | Blocks array size
+
  | Yaw
  | VarInt
+
  | {{Type|Float}}
  | Number of elements in the following array.
+
  | Absolute or relative rotation on the X axis, in degrees.
 
  |-
 
  |-
  | Blocks
+
  | Pitch
  | Array of VarLong
+
  | {{Type|Float}}
  | Each entry is composed of the block state id, shifted left by 12, and the relative block position in the chunk section (4 bits for x, z, and y, from left to right).
+
  | Absolute or relative rotation on the Y axis, in degrees.
  |}
+
  |-
 
+
| Flags
Chunk section position is encoded:
+
| {{Type|Byte}}
<syntaxhighlight lang="java">
+
| Reference the Flags table below. When the value of the this byte masked is zero the field is absolute, otherwise relative.
((sectionX & 0x3FFFFF) << 42) | (sectionY & 0xFFFFF) | ((sectionZ & 0x3FFFFF) << 20);
+
|-
</syntaxhighlight>
+
| Teleport ID
and decoded:
+
| {{Type|VarInt}}
<syntaxhighlight lang="java">
+
| Client should confirm this packet with [[#Confirm Teleportation|Confirm Teleportation]] containing the same Teleport ID.
sectionX = long >> 42;
+
|}
sectionY = long << 44 >> 44;
 
sectionZ = long << 22 >> 42;
 
</syntaxhighlight>
 
  
Blocks are encoded:
+
{| class="wikitable"  
<syntaxhighlight lang="java">
+
|+ Flags
blockStateId << 12 | (blockLocalX << 8 | blockLocalZ << 4 | blockLocalY)
+
|-
//Uses the local position of the given block position relative to its respective chunk section
+
! Field
</syntaxhighlight>
+
! Hex Mask
 +
|-
 +
| X
 +
| 0x01
 +
|-
 +
| Y
 +
| 0x02
 +
|-
 +
| Z
 +
| 0x04
 +
|-
 +
| Y_ROT (Pitch)
 +
| 0x08
 +
|-
 +
| X_ROT (Yaw)
 +
| 0x10
 +
|}
  
==== Select Advancements Tab ====
+
==== Update Recipe Book ====
 
 
Sent by the server to indicate that the client should switch advancement tab. Sent either when the client switches tab in the GUI or when an advancement in another tab is made.
 
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 4,961: Line 5,302:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="2"| 0x46
+
  | rowspan="14"| 0x41
  | rowspan="2"| Play
+
  | rowspan="14"| Play
  | rowspan="2"| Client
+
  | rowspan="14"| Client
| Has id
 
| Boolean
 
| Indicates if the next field is present.
 
 
  |-
 
  |-
  | Optional Identifier
+
  | Action
  | Identifier
+
  | {{Type|VarInt}}
| See below.
+
  | 0: init, 1: add, 2: remove.
  |}
 
 
 
The Identifier can be one of the following:
 
 
 
{| class="wikitable"
 
! Optional Identifier
 
 
  |-
 
  |-
  | minecraft:story/root
+
  | Crafting Recipe Book Open
 +
| {{Type|Boolean}}
 +
| If true, then the crafting recipe book will be open when the player opens its inventory.
 +
|-
 +
| Crafting Recipe Book Filter Active
 +
| {{Type|Boolean}}
 +
| If true, then the filtering option is active when the players opens its inventory.
 +
|-
 +
| Smelting Recipe Book Open
 +
| {{Type|Boolean}}
 +
| If true, then the smelting recipe book will be open when the player opens its inventory.
 +
|-
 +
| Smelting Recipe Book Filter Active
 +
| {{Type|Boolean}}
 +
| If true, then the filtering option is active when the players opens its inventory.
 +
|-
 +
| Blast Furnace Recipe Book Open
 +
| {{Type|Boolean}}
 +
| If true, then the blast furnace recipe book will be open when the player opens its inventory.
 +
|-
 +
| Blast Furnace Recipe Book Filter Active
 +
| {{Type|Boolean}}
 +
| If true, then the filtering option is active when the players opens its inventory.
 +
|-
 +
| Smoker Recipe Book Open
 +
| {{Type|Boolean}}
 +
| If true, then the smoker recipe book will be open when the player opens its inventory.
 +
|-
 +
| Smoker Recipe Book Filter Active
 +
| {{Type|Boolean}}
 +
| If true, then the filtering option is active when the players opens its inventory.
 
  |-
 
  |-
  | minecraft:nether/root
+
  | Array size 1
 +
| {{Type|VarInt}}
 +
| Number of elements in the following array.
 
  |-
 
  |-
  | minecraft:end/root
+
  | Recipe IDs
 +
| {{Type|Array}} of {{Type|Identifier}}
 +
|
 
  |-
 
  |-
  | minecraft:adventure/root
+
  | Array size 2
 +
| {{Type|Optional}} {{Type|VarInt}}
 +
| Number of elements in the following array, only present if action is 0 (init).
 
  |-
 
  |-
  | minecraft:husbandry/root
+
  | Recipe IDs
 +
| {{Type|Optional}} {{Type|Array}} of {{Type|Identifier}}
 +
| Only present if mode is 0 (init)
 
  |}
 
  |}
 +
Action:
 +
* 0 (init) = All the recipes in list 1 will be tagged as displayed, and all the recipes in list 2 will be added to the recipe book. Recipes that aren't tagged will be shown in the notification.
 +
* 1 (add) = All the recipes in the list are added to the recipe book and their icons will be shown in the notification.
 +
* 2 (remove) = Remove all the recipes in the list. This allows them to be re-displayed when they are re-added.
  
If no or an invalid identifier is sent, the client will switch to the first tab in the GUI.
+
==== Remove Entities ====
  
==== Server Data ====
+
Sent by the server when an entity is to be destroyed on the client.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 5,001: Line 5,375:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="5"| 0x47
+
  | rowspan="2"| 0x42
  | rowspan="5"| Play
+
  | rowspan="2"| Play
  | rowspan="5"| Client
+
  | rowspan="2"| Client
  | MOTD
+
  | Count
  | [[#Definitions:chat|Chat]]
+
  | {{Type|VarInt}}
  |
+
  | Number of elements in the following array.
 
  |-
 
  |-
  | Has Icon
+
  | Entity IDs
  | [[#Definitions:boolean|Boolean]]
+
  | {{Type|Array}} of {{Type|VarInt}}
|
+
  | The list of entities to destroy.
|-
+
  |}
| Size
 
| VarInt
 
  | Number of bytes in the following array.
 
|-
 
| Icon
 
| Optional [[#Definitions:byte-array|Byte Array]]
 
| Icon bytes in the PNG format
 
|-
 
| Enforces Secure Chat
 
| [[#Definitions:boolean|Boolean]]
 
|
 
  |}
 
  
==== Set Action Bar Text ====
+
==== Remove Entity Effect ====
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 5,035: Line 5,397:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
| rowspan="1"| 0x48
+
  | rowspan="2"| 0x43
| rowspan="1"| Play
 
| rowspan="1"| Client
 
| Action bar text
 
| [[Chat]]
 
| Displays a message above the hotbar (the same as position 2 in [[#Player Chat Message|Player Chat Message]].
 
|}
 
 
 
==== Set Border Center ====
 
 
 
{| class="wikitable"
 
! Packet ID
 
! State
 
! Bound To
 
! Field Name
 
! Field Type
 
! Notes
 
|-
 
  | rowspan="2"| 0x49
 
 
  | rowspan="2"| Play
 
  | rowspan="2"| Play
 
  | rowspan="2"| Client
 
  | rowspan="2"| Client
  | X
+
  | Entity ID
  | Double
+
  | {{Type|VarInt}}
 
  |
 
  |
 
  |-
 
  |-
  | Z
+
  | Effect ID
  | Double
+
  | {{Type|VarInt}}
  |
+
  | See {{Minecraft Wiki|Status effect#Effect list|this table}}.
 
  |}
 
  |}
  
==== Set Border Lerp Size ====
+
==== Reset Score ====
 +
 
 +
This is sent to the client when it should remove a scoreboard item.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 5,075: Line 5,421:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="3"| 0x4A
+
  | rowspan="3"| 0x44
 
  | rowspan="3"| Play
 
  | rowspan="3"| Play
 
  | rowspan="3"| Client
 
  | rowspan="3"| Client
  | Old Diameter
+
  | Entity Name
  | Double
+
  | {{Type|String}} (32767)
  | Current length of a single side of the world border, in meters.
+
  | The entity whose score this is. For players, this is their username; for other entities, it is their UUID.
 
  |-
 
  |-
  | New Diameter
+
  | Has Objective Name
  | Double
+
  | {{Type|Boolean}}
  | Target length of a single side of the world border, in meters.
+
  | Whether the score should be removed for the specified objective, or for all of them.
 
  |-
 
  |-
  | Speed
+
  | Objective Name
  | VarLong
+
  | {{Type|Optional}} {{Type|String}} (32767)
  | Number of real-time ''milli''seconds until New Diameter is reached. It appears that Notchian server does not sync world border speed to game ticks, so it gets out of sync with server lag. If the world border is not moving, this is set to 0.
+
  | The name of the objective the score belongs to. Only present if the previous field is true.
 
  |}
 
  |}
  
==== Set Border Size ====
+
==== Remove Resource Pack (play) ====
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 5,101: Line 5,447:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="1"| 0x4B
+
  | rowspan="2"| 0x45
  | rowspan="1"| Play
+
  | rowspan="2"| Play
  | rowspan="1"| Client
+
  | rowspan="2"| Client
  | Diameter
+
  | Has UUID
  | Double
+
  | {{Type|Boolean}}
  | Length of a single side of the world border, in meters.
+
  | Whether a specific resource pack should be removed, or all of them.
 +
|-
 +
| UUID
 +
| {{Type|Optional}} {{Type|UUID}}
 +
| The UUID of the resource pack to be removed. Only present if the previous field is true.
 
  |}
 
  |}
  
==== Set Border Warning Delay ====
+
==== Add Resource Pack (play) ====
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 5,119: Line 5,469:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="1"| 0x4C
+
  | rowspan="6"| 0x46
  | rowspan="1"| Play
+
  | rowspan="6"| Play
  | rowspan="1"| Client
+
  | rowspan="6"| Client
  | Warning Time
+
  | UUID
  | VarInt
+
  | {{Type|UUID}}
  | In seconds as set by <code>/worldborder warning time</code>.
+
  | The unique identifier of the resource pack.
  |}
+
  |-
 
+
| URL
==== Set Border Warning Distance ====
+
| {{Type|String}} (32767)
 
+
| The URL to the resource pack.
{| class="wikitable"
+
|-
  ! Packet ID
+
| Hash
  ! State
+
| {{Type|String}} (40)
  ! Bound To
+
| A 40 character hexadecimal, case-insensitive [[wikipedia:SHA-1|SHA-1]] hash of the resource pack file.<br />If it's not a 40 character hexadecimal string, the client will not use it for hash verification and likely waste bandwidth.
  ! Field Name
+
|-
  ! Field Type
+
| Forced
  ! Notes
+
  | {{Type|Boolean}}
 +
  | The Notchian client will be forced to use the resource pack from the server. If they decline they will be kicked from the server.
 +
  |-
 +
  | Has Prompt Message
 +
  | {{Type|Boolean}}
 +
  | Whether a custom message should be used on the resource pack prompt.
 
  |-
 
  |-
  | rowspan="1"| 0x4D
+
  | Prompt Message
| rowspan="1"| Play
+
  | {{Type|Optional}} {{Type|Text Component}}
  | rowspan="1"| Client
+
  | This is shown in the prompt making the client accept or decline the resource pack. Only present if the previous field is true.
| Warning Blocks
 
| VarInt
 
  | In meters.
 
 
  |}
 
  |}
  
==== Set Camera ====
+
==== Respawn ====
  
Sets the entity that the player renders from. This is normally used when the player left-clicks an entity while in spectator mode.
+
{{Need Info|Although the number of portal cooldown ticks is included in this packet, the whole portal usage process is still dictated entirely by the server. What kind of effect does this value have on the client, if any?}}
  
The player's camera will move with the entity and look where it is looking. The entity is often another player, but can be any type of entity.  The player is unable to move this entity (move packets will act as if they are coming from the other entity).
+
To change the player's dimension (overworld/nether/end), send them a respawn packet with the appropriate dimension, followed by prechunks/chunks for the new dimension, and finally a position and look packet. You do not need to unload chunks, the client will do it automatically.
 
 
If the given entity is not loaded by the player, this packet is ignored. To return control to the player, send this packet with their entity ID.
 
 
 
The Notchian server resets this (sends it back to the default entity) whenever the spectated entity is killed or the player sneaks, but only if they were spectating an entity. It also sends this packet whenever the player switches out of spectator mode (even if they weren't spectating an entity).
 
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 5,163: Line 5,511:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | 0x4E
+
  | rowspan="12"| 0x47
  | Play
+
  | rowspan="12"| Play
  | Client
+
  | rowspan="12"| Client
  | Camera ID
+
  | Dimension Type
  | VarInt
+
  | {{Type|VarInt}}
  | ID of the entity to set the client's camera to.
+
  | The ID of type of dimension in the <code>minecraft:dimension_type</code> registry, defined by the [[Protocol#Registry_Data|Registry Data]] packet.
  |}
+
|-
 
+
| Dimension Name
The notchian client also loads certain shaders for given entities:
+
| {{Type|Identifier}}
 
+
| Name of the dimension being spawned into.
* Creeper &rarr; <code>shaders/post/creeper.json</code>
+
|-
* Spider (and cave spider) &rarr; <code>shaders/post/spider.json</code>
+
| Hashed seed
* Enderman &rarr; <code>shaders/post/invert.json</code>
+
| {{Type|Long}}
* Anything else &rarr; the current shader is unloaded
+
| First 8 bytes of the SHA-256 hash of the world's seed. Used client side for biome noise
 +
|-
 +
| Game mode
 +
  | {{Type|Unsigned Byte}}
 +
| 0: Survival, 1: Creative, 2: Adventure, 3: Spectator.
 +
|-
 +
| Previous Game mode
 +
| {{Type|Byte}}
 +
| -1: Undefined (null), 0: Survival, 1: Creative, 2: Adventure, 3: Spectator. The previous game mode. Vanilla client uses this for the debug (F3 + N & F3 + F4) game mode switch. (More information needed)
 +
|-
 +
| Is Debug
 +
| {{Type|Boolean}}
 +
| True if the world is a {{Minecraft Wiki|debug mode}} world; debug mode worlds cannot be modified and have predefined blocks.
 +
|-
 +
| Is Flat
 +
| {{Type|Boolean}}
 +
| True if the world is a {{Minecraft Wiki|superflat}} world; flat worlds have different void fog and a horizon at y=0 instead of y=63.
 +
|-
 +
| Has death location
 +
| {{Type|Boolean}}
 +
| If true, then the next two fields are present.
 +
|-
 +
| Death dimension Name
 +
| {{Type|Optional}} {{Type|Identifier}}
 +
| Name of the dimension the player died in.
 +
|-
 +
| Death location
 +
| {{Type|Optional}} {{Type|Position}}
 +
| The location that the player died at.
 +
|-
 +
| Portal cooldown
 +
| {{Type|VarInt}}
 +
| The number of ticks until the player can use the portal again.
 +
|-
 +
| Data kept
 +
| {{Type|Byte}}
 +
| Bit mask. 0x01: Keep attributes, 0x02: Keep metadata. Tells which data should be kept on the client side once the player has respawned.
 +
In the Notchian implementation, this is context dependent:
 +
* normal respawns (after death) keep no data;
 +
* exiting the end poem/credits keeps the attributes;
 +
* other dimension changes (portals or teleports) keep all data.
 +
|}
 +
 
 +
{{Warning2|Avoid changing player's dimension to same dimension they were already in unless they are dead. If you change the dimension to one they are already in, weird bugs can occur, such as the player being unable to attack other players in new world (until they die and respawn).
 +
 
 +
Before 1.16, if you must respawn a player in the same dimension without killing them, send two respawn packets, one to a different world and then another to the world you want. You do not need to complete the first respawn; it only matters that you send two packets.}}
 +
 
 +
==== Set Head Rotation ====
  
==== Set Held Item ====
+
Changes the direction an entity's head is facing.
  
Sent to change the player's slot selection.
+
While sending the Entity Look packet changes the vertical rotation of the head, sending this packet appears to be necessary to rotate the head horizontally.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 5,190: Line 5,585:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | 0x4F
+
  | rowspan="2"| 0x48
  | Play
+
  | rowspan="2"| Play
  | Client
+
  | rowspan="2"| Client
  | Slot
+
  | Entity ID
  | Byte
+
  | {{Type|VarInt}}
  | The slot which the player has selected (0–8).
+
|
 +
|-
 +
| Head Yaw
 +
| {{Type|Angle}}
 +
  | New angle, not a delta.
 
  |}
 
  |}
  
==== Set Center Chunk ====
+
==== Update Section Blocks ====
  
{{Need Info|Why is this even needed?  Is there a better name for it?  My guess is that it's something to do with logical behavior with latency, but it still seems weird.}}
+
Fired whenever 2 or more blocks are changed within the same chunk on the same tick.
  
Updates the client's location.  This is used to determine what chunks should remain loaded and if a chunk load should be ignored; chunks outside of the view distance may be unloaded.
+
{{Warning|Changing blocks in chunks not loaded by the client is unsafe (see note on [[#Block Update|Block Update]]).}}
 
 
Sent whenever the player moves across a chunk border horizontally, and also (according to testing) for any integer change in the vertical axis, even if it doesn't go across a chunk section border.
 
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 5,214: Line 5,611:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="2"| 0x50
+
  | rowspan="3"| 0x49
  | rowspan="2"| Play
+
  | rowspan="3"| Play
  | rowspan="2"| Client
+
  | rowspan="3"| Client
  | Chunk X
+
  | Chunk section position
  | VarInt
+
  | {{Type|Long}}
  | Chunk X coordinate of the player's position.
+
  | Chunk section coordinate (encoded chunk x and z with each 22 bits, and section y with 20 bits, from left to right).
 +
|-
 +
| Blocks array size
 +
| {{Type|VarInt}}
 +
| Number of elements in the following array.
 
  |-
 
  |-
  | Chunk Z
+
  | Blocks
  | VarInt
+
  | {{Type|Array}} of {{Type|VarLong}}
  | Chunk Z coordinate of the player's position.
+
  | Each entry is composed of the block state id, shifted left by 12, and the relative block position in the chunk section (4 bits for x, z, and y, from left to right).
 
  |}
 
  |}
  
==== Set Render Distance ====
+
Chunk section position is encoded:
 +
<syntaxhighlight lang="java">
 +
((sectionX & 0x3FFFFF) << 42) | (sectionY & 0xFFFFF) | ((sectionZ & 0x3FFFFF) << 20);
 +
</syntaxhighlight>
 +
and decoded:
 +
<syntaxhighlight lang="java">
 +
sectionX = long >> 42;
 +
sectionY = long << 44 >> 44;
 +
sectionZ = long << 22 >> 42;
 +
</syntaxhighlight>
  
Sent by the integrated singleplayer server when changing render distance.  This packet is sent by the server when the client reappears in the overworld after leaving the end.
+
Blocks are encoded:
 +
<syntaxhighlight lang="java">
 +
blockStateId << 12 | (blockLocalX << 8 | blockLocalZ << 4 | blockLocalY)
 +
//Uses the local position of the given block position relative to its respective chunk section
 +
</syntaxhighlight>
 +
and decoded:
 +
<syntaxhighlight lang="java">
 +
blockStateId = long >> 12;
 +
blockLocalX = (long >> 8) & 0xF;
 +
blockLocalY = long & 0xF;
 +
blockLocalZ = (long >> 4) & 0xF;
 +
</syntaxhighlight>
  
{| class="wikitable"
+
==== Select Advancements Tab ====
! Packet ID
 
! State
 
! Bound To
 
! Field Name
 
! Field Type
 
! Notes
 
|-
 
| 0x51
 
| Play
 
| Client
 
| View Distance
 
| VarInt
 
| Render distance (2-32).
 
|}
 
  
==== Set Default Spawn Position ====
+
Sent by the server to indicate that the client should switch advancement tab. Sent either when the client switches tab in the GUI or when an advancement in another tab is made.
 
 
Sent by the server after login to specify the coordinates of the spawn point (the point at which players spawn at, and which the compass points to). It can be sent at any time to update the point compasses point at.
 
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 5,258: Line 5,663:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="2"| 0x52
+
  | rowspan="2"| 0x4A
 
  | rowspan="2"| Play
 
  | rowspan="2"| Play
 
  | rowspan="2"| Client
 
  | rowspan="2"| Client
  | Location
+
  | Has id
  | Position
+
  | {{Type|Boolean}}
  | Spawn location.
+
  | Indicates if the next field is present.
 
  |-
 
  |-
  | Angle
+
  | Identifier
  | Float
+
  | {{Type|Optional}} {{Type|Identifier}}
  | The angle at which to respawn at.
+
| See below.
 +
  |}
 +
 
 +
The {{Type|Identifier}} can be one of the following:
 +
 
 +
{| class="wikitable"
 +
! Identifier
 +
|-
 +
| minecraft:story/root
 +
|-
 +
| minecraft:nether/root
 +
|-
 +
| minecraft:end/root
 +
|-
 +
| minecraft:adventure/root
 +
|-
 +
| minecraft:husbandry/root
 
  |}
 
  |}
  
==== Display Objective ====
+
If no or an invalid identifier is sent, the client will switch to the first tab in the GUI.
  
This is sent to the client when it should display a scoreboard.
+
==== Server Data ====
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 5,282: Line 5,703:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="2"| 0x53
+
  | rowspan="4"| 0x4B
  | rowspan="2"| Play
+
  | rowspan="4"| Play
  | rowspan="2"| Client
+
  | rowspan="4"| Client
  | Position
+
  | MOTD
  | VarInt
+
  | {{Type|Text Component}}
  | The position of the scoreboard. 0: list, 1: sidebar, 2: below name, 3 - 18: team specific sidebar, indexed as 3 + team color.
+
|
 +
|-
 +
| Has Icon
 +
| {{Type|Boolean}}
 +
|
 +
|-
 +
| Size
 +
| {{Type|Optional}} {{Type|VarInt}}
 +
  | Number of bytes in the following array. Only present if Has Icon is true.
 
  |-
 
  |-
  | Score Name
+
  | Icon
  | String (32767)
+
  | {{Type|Optional}} {{Type|Byte Array}}
  | The unique name for the scoreboard to be displayed.
+
  | Icon bytes in the PNG format. Only present is Has Icon is true.
 
  |}
 
  |}
  
==== Set Entity Metadata ====
+
==== Set Action Bar Text ====
  
Updates one or more [[Entity_metadata#Entity Metadata Format|metadata]] properties for an existing entity. Any properties not included in the Metadata field are left unchanged.
+
Displays a message above the hotbar. Equivalent to [[#System Chat Message|System Chat Message]] with Overlay set to true, except that [[Chat#Social Interactions (blocking)|chat message blocking]] isn't performed. Used by the Notchian server only to implement the <code>/title</code> command.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 5,306: Line 5,735:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="2"| 0x54
+
  | rowspan="1"| 0x4C
  | rowspan="2"| Play
+
  | rowspan="1"| Play
  | rowspan="2"| Client
+
  | rowspan="1"| Client
  | Entity ID
+
  | Action bar text
  | VarInt
+
  | {{Type|Text Component}}
|
 
|-
 
| Metadata
 
| [[Entity_metadata#Entity Metadata Format|Entity Metadata]]
 
|
 
 
  |}
 
  |}
  
==== Link Entities ====
+
==== Set Border Center ====
 
 
This packet is sent when an entity has been {{Minecraft Wiki|Lead|leashed}} to another entity.
 
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 5,330: Line 5,752:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="2"| 0x55
+
  | rowspan="2"| 0x4D
 
  | rowspan="2"| Play
 
  | rowspan="2"| Play
 
  | rowspan="2"| Client
 
  | rowspan="2"| Client
  | Attached Entity ID
+
  | X
  | Int
+
  | {{Type|Double}}
  | Attached entity's EID.
+
  |
 
  |-
 
  |-
  | Holding Entity ID
+
  | Z
  | Int
+
  | {{Type|Double}}
  | ID of the entity holding the lead. Set to -1 to detach.
+
  |
 
  |}
 
  |}
  
==== Set Entity Velocity ====
+
==== Set Border Lerp Size ====
 
 
Velocity is in units of 1/8000 of a block per server tick (50ms); for example, -1343 would move (-1343 / 8000) = −0.167875 blocks per tick (or −3.3575 blocks per second).
 
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 5,354: Line 5,774:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="4"| 0x56
+
  | rowspan="3"| 0x4E
  | rowspan="4"| Play
+
  | rowspan="3"| Play
  | rowspan="4"| Client
+
  | rowspan="3"| Client
  | Entity ID
+
  | Old Diameter
  | VarInt
+
  | {{Type|Double}}
  |
+
  | Current length of a single side of the world border, in meters.
 
  |-
 
  |-
  | Velocity X
+
  | New Diameter
  | Short
+
  | {{Type|Double}}
  | Velocity on the X axis.
+
  | Target length of a single side of the world border, in meters.
 
  |-
 
  |-
  | Velocity Y
+
  | Speed
  | Short
+
  | {{Type|VarLong}}
| Velocity on the Y axis.
+
  | Number of real-time ''milli''seconds until New Diameter is reached. It appears that Notchian server does not sync world border speed to game ticks, so it gets out of sync with server lag. If the world border is not moving, this is set to 0.
  |-
 
| Velocity Z
 
| Short
 
| Velocity on the Z axis.
 
 
  |}
 
  |}
  
==== Set Equipment ====
+
==== Set Border Size ====
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 5,380: Line 5,796:
 
  ! State
 
  ! State
 
  ! Bound To
 
  ! Bound To
  ! colspan="2"| Field Name
+
  ! Field Name
  ! colspan="2"| Field Type
+
  ! Field Type
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="3"| 0x57
+
  | rowspan="1"| 0x4F
  | rowspan="3"| Play
+
  | rowspan="1"| Play
  | rowspan="3"| Client
+
  | rowspan="1"| Client
  | colspan="2"| Entity ID
+
  | Diameter
| colspan="2"| VarInt
+
  | {{Type|Double}}
| Entity's ID.
+
  | Length of a single side of the world border, in meters.
|-
 
  | rowspan="2"| Equipment
 
| Slot
 
  | rowspan="2"| Array
 
| Byte Enum
 
| Equipment slot. 0: main hand, 1: off hand, 2–5: armor slot (2: boots, 3: leggings, 4: chestplate, 5: helmet).  Also has the top bit set if another entry follows, and otherwise unset if this is the last item in the array.
 
|-
 
| Item
 
| [[Slot Data|Slot]]
 
|
 
 
  |}
 
  |}
  
==== Set Experience ====
+
==== Set Border Warning Delay ====
 
 
Sent by the server when the client should change experience levels.
 
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 5,414: Line 5,818:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="3"| 0x58
+
  | rowspan="1"| 0x50
  | rowspan="3"| Play
+
  | rowspan="1"| Play
  | rowspan="3"| Client
+
  | rowspan="1"| Client
  | Experience bar
+
  | Warning Time
  | Float
+
  | {{Type|VarInt}}
| Between 0 and 1.
+
  | In seconds as set by <code>/worldborder warning time</code>.
|-
 
| Level
 
| VarInt
 
  |
 
|-
 
| Total Experience
 
| VarInt
 
| See {{Minecraft Wiki|Experience#Leveling up}} on the Minecraft Wiki for Total Experience to Level conversion.
 
 
  |}
 
  |}
  
==== Set Health ====
+
==== Set Border Warning Distance ====
 
 
Sent by the server to set the health of the player it is sent to.
 
 
 
Food {{Minecraft Wiki|Food#Hunger vs. Saturation|saturation}} acts as a food “overcharge”. Food values will not decrease while the saturation is over zero. New players logging in or respawning automatically get a saturation of 5.0. Eating food increases the saturation as well as the food bar.
 
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 5,444: Line 5,836:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="3"| 0x59
+
  | rowspan="1"| 0x51
  | rowspan="3"| Play
+
  | rowspan="1"| Play
  | rowspan="3"| Client
+
  | rowspan="1"| Client
  | Health
+
  | Warning Blocks
  | Float
+
  | {{Type|VarInt}}
| 0 or less = dead, 20 = full HP.
+
  | In meters.
|-
 
| Food
 
| VarInt
 
  | 0–20.
 
|-
 
| Food Saturation
 
| Float
 
| Seems to vary from 0.0 to 5.0 in integer increments.
 
 
  |}
 
  |}
  
==== Update Objectives ====
+
==== Set Camera ====
 +
 
 +
Sets the entity that the player renders from. This is normally used when the player left-clicks an entity while in spectator mode.
 +
 
 +
The player's camera will move with the entity and look where it is looking. The entity is often another player, but can be any type of entity.  The player is unable to move this entity (move packets will act as if they are coming from the other entity).
 +
 
 +
If the given entity is not loaded by the player, this packet is ignored.  To return control to the player, send this packet with their entity ID.
  
This is sent to the client when it should create a new {{Minecraft Wiki|scoreboard}} objective or remove one.
+
The Notchian server resets this (sends it back to the default entity) whenever the spectated entity is killed or the player sneaks, but only if they were spectating an entity. It also sends this packet whenever the player switches out of spectator mode (even if they weren't spectating an entity).
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 5,472: Line 5,862:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="4"| 0x5A
+
  | 0x52
  | rowspan="4"| Play
+
  | Play
  | rowspan="4"| Client
+
  | Client
  | Objective Name
+
  | Camera ID
  | String (32767)
+
  | {{Type|VarInt}}
| A unique name for the objective.
+
  | ID of the entity to set the client's camera to.
|-
 
| Mode
 
| Byte
 
  | 0 to create the scoreboard. 1 to remove the scoreboard. 2 to update the display text.
 
|-
 
| Objective Value
 
| Optional Chat
 
| Only if mode is 0 or 2. The text to be displayed for the score.
 
|-
 
| Type
 
| Optional VarInt Enum
 
| Only if mode is 0 or 2. 0 = "integer", 1 = "hearts".
 
 
  |}
 
  |}
  
==== Set Passengers ====
+
The notchian client also loads certain shaders for given entities:
 +
 
 +
* Creeper &rarr; <code>shaders/post/creeper.json</code>
 +
* Spider (and cave spider) &rarr; <code>shaders/post/spider.json</code>
 +
* Enderman &rarr; <code>shaders/post/invert.json</code>
 +
* Anything else &rarr; the current shader is unloaded
 +
 
 +
==== Set Held Item (clientbound) ====
 +
 
 +
Sent to change the player's slot selection.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 5,502: Line 5,889:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="3"| 0x5B
+
  | 0x53
  | rowspan="3"| Play
+
  | Play
  | rowspan="3"| Client
+
  | Client
  | Entity ID
+
  | Slot
  | VarInt
+
  | {{Type|Byte}}
  | Vehicle's EID.
+
  | The slot which the player has selected (0–8).
 +
|}
 +
 
 +
==== Set Center Chunk ====
 +
 
 +
Sets the center position of the client's chunk loading area. The area is square-shaped, spanning 2 &times; server view distance + 7 chunks on both axes (width, not radius!). Since the area's width is always an odd number, there is no ambiguity as to which chunk is the center.
 +
 
 +
The Notchian client ignores attempts to send chunks located outside the loading area, and immediately unloads any existing chunks no longer inside it.
 +
 
 +
The center chunk is normally the chunk the player is in, but apart from the implications on chunk loading, the (Notchian) client takes no issue with this not being the case. Indeed, as long as chunks are sent only within the default loading area centered on the world origin, it is not necessary to send this packet at all. This may be useful for servers with small bounded worlds, such as minigames, since it ensures chunks never need to be resent after the client has joined, saving on bandwidth.
 +
 
 +
The Notchian server sends this packet whenever the player moves across a chunk border horizontally, and also (according to testing) for any integer change in the vertical axis, even if it doesn't go across a chunk section border.
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 
  |-
 
  |-
  | Passenger Count
+
  | rowspan="2"| 0x54
  | VarInt
+
  | rowspan="2"| Play
  | Number of elements in the following array.
+
| rowspan="2"| Client
 +
| Chunk X
 +
| {{Type|VarInt}}
 +
  | Chunk X coordinate of the loading area center.
 
  |-
 
  |-
  | Passengers
+
  | Chunk Z
  | Array of VarInt
+
  | {{Type|VarInt}}
  | EIDs of entity's passengers.
+
  | Chunk Z coordinate of the loading area center.
 
  |}
 
  |}
  
==== Update Teams ====
+
==== Set Render Distance ====
  
Creates and updates teams.
+
Sent by the integrated singleplayer server when changing render distance.  This packet is sent by the server when the client reappears in the overworld after leaving the end.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 5,526: Line 5,935:
 
  ! State
 
  ! State
 
  ! Bound To
 
  ! Bound To
  ! colspan="2"| Field Name
+
  ! Field Name
 
  ! Field Type
 
  ! Field Type
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="23"| 0x5C
+
  | 0x55
  | rowspan="23"| Play
+
| Play
  | rowspan="23"| Client
+
  | Client
  | colspan="2"| Team Name
+
| View Distance
  | String (32767)
+
  | {{Type|VarInt}}
| A unique name for the team. (Shared with scoreboard).
+
  | Render distance (2-32).
 +
  |}
 +
 
 +
==== Set Default Spawn Position ====
 +
 
 +
Sent by the server after login to specify the coordinates of the spawn point (the point at which players spawn at, and which the compass points to). It can be sent at any time to update the point compasses point at.
 +
 
 +
The client uses this as the default position of the player upon spawning, though it's a good idea to always override this default by sending [[#Synchronize Player Position|Synchronize Player Position]]. When converting the position to floating point, 0.5 is added to the x and z coordinates and 1.0 to the y coordinate, so as to place the player centered on top of the specified block position.
 +
 
 +
Before receiving this packet, the client uses the default position 8, 64, 8, and angle 0.0 (resulting in a default player spawn position of 8.5, 65.0, 8.5).
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 
  |-
 
  |-
  | colspan="2"| Mode
+
  | rowspan="2"| 0x56
  | Byte
+
  | rowspan="2"| Play
  | Determines the layout of the remaining packet.
+
| rowspan="2"| Client
 +
| Location
 +
| {{Type|Position}}
 +
  | Spawn location.
 
  |-
 
  |-
  | rowspan="9"| 0: create team
+
  | Angle
  | Team Display Name
+
| {{Type|Float}}
  | Chat
+
| The angle at which to respawn at.
  |
+
|}
 +
 
 +
==== Display Objective ====
 +
 
 +
This is sent to the client when it should display a scoreboard.
 +
 
 +
{| class="wikitable"
 +
  ! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
  ! Field Type
 +
  ! Notes
 
  |-
 
  |-
  | Friendly Flags
+
  | rowspan="2"| 0x57
  | Byte
+
| rowspan="2"| Play
  | Bit mask. 0x01: Allow friendly fire, 0x02: can see invisible players on same team.
+
  | rowspan="2"| Client
 +
  | Position
 +
| {{Type|VarInt}}
 +
| The position of the scoreboard. 0: list, 1: sidebar, 2: below name, 3 - 18: team specific sidebar, indexed as 3 + team color.
 
  |-
 
  |-
  | Name Tag Visibility
+
  | Score Name
  | String Enum (40)
+
  | {{Type|String}} (32767)
  | <code>always</code>, <code>hideForOtherTeams</code>, <code>hideForOwnTeam</code>, <code>never</code>.
+
  | The unique name for the scoreboard to be displayed.
  |-
+
  |}
| Collision Rule
+
 
  | String Enum (40)
+
==== Set Entity Metadata ====
  | <code>always</code>, <code>pushOtherTeams</code>, <code>pushOwnTeam</code>, <code>never</code>.
+
 
  |-
+
Updates one or more [[Entity_metadata#Entity Metadata Format|metadata]] properties for an existing entity. Any properties not included in the Metadata field are left unchanged.
  | Team Color
+
 
  | VarInt Enum
+
{| class="wikitable"
  | Used to color the name of players on the team; see below.
+
  ! Packet ID
 +
  ! State
 +
  ! Bound To
 +
  ! Field Name
 +
  ! Field Type
 +
  ! Notes
 
  |-
 
  |-
  | Team Prefix
+
  | rowspan="2"| 0x58
| Chat
+
  | rowspan="2"| Play
  | Displayed before the names of players that are part of this team.
+
  | rowspan="2"| Client
|-
+
  | Entity ID
  | Team Suffix
+
  | {{Type|VarInt}}
| Chat
 
  | Displayed after the names of players that are part of this team.
 
  |-
 
| Entity Count
 
| VarInt
 
| Number of elements in the following array.
 
|-
 
| Entities
 
| Array of String (32767)
 
| Identifiers for the entities in this team.  For players, this is their username; for other entities, it is their UUID.
 
|-
 
| 1: remove team
 
| ''no fields''
 
| ''no fields''
 
 
  |
 
  |
 
  |-
 
  |-
  | rowspan="7"| 2: update team info
+
  | Metadata
  | Team Display Name
+
  | [[Entity_metadata#Entity Metadata Format|Entity Metadata]]
| Chat
 
 
  |
 
  |
 +
|}
 +
 +
==== Link Entities ====
 +
 +
This packet is sent when an entity has been {{Minecraft Wiki|Lead|leashed}} to another entity.
 +
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 
  |-
 
  |-
  | Friendly Flags
+
  | rowspan="2"| 0x59
  | Byte
+
  | rowspan="2"| Play
  | Bit mask. 0x01: Allow friendly fire, 0x02: can see invisible entities on same team.
+
| rowspan="2"| Client
 +
| Attached Entity ID
 +
| {{Type|Int}}
 +
  | Attached entity's EID.
 
  |-
 
  |-
  | Name Tag Visibility
+
  | Holding Entity ID
  | String Enum (40)
+
| {{Type|Int}}
  | <code>always</code>, <code>hideForOtherTeams</code>, <code>hideForOwnTeam</code>, <code>never</code>
+
  | ID of the entity holding the lead. Set to -1 to detach.
 +
  |}
 +
 
 +
==== Set Entity Velocity ====
 +
 
 +
Velocity is in units of 1/8000 of a block per server tick (50ms); for example, -1343 would move (-1343 / 8000) = −0.167875 blocks per tick (or −3.3575 blocks per second).
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 
  |-
 
  |-
  | Collision Rule
+
  | rowspan="4"| 0x5A
  | String Enum (40)
+
  | rowspan="4"| Play
  | <code>always</code>, <code>pushOtherTeams</code>, <code>pushOwnTeam</code>, <code>never</code>
+
| rowspan="4"| Client
 +
| Entity ID
 +
| {{Type|VarInt}}
 +
  |
 
  |-
 
  |-
  | Team Color
+
  | Velocity X
  | VarInt Enum
+
  | {{Type|Short}}
  | Used to color the name of players on the team; see below.
+
  | Velocity on the X axis.
 
  |-
 
  |-
  | Team Prefix
+
  | Velocity Y
  | Chat
+
  | {{Type|Short}}
  | Displayed before the names of players that are part of this team.
+
  | Velocity on the Y axis.
 
  |-
 
  |-
  | Team Suffix
+
  | Velocity Z
  | Chat
+
  | {{Type|Short}}
| Displayed after the names of players that are part of this team.
+
  | Velocity on the Z axis.
|-
 
| rowspan="2"| 3: add entities to team
 
| Entity Count
 
| VarInt
 
  | Number of elements in the following array.
 
|-
 
| Entities
 
| Array of String (32767)
 
| Identifiers for the added entities.  For players, this is their username; for other entities, it is their UUID.
 
|-
 
| rowspan="2"| 4: remove entities from team
 
| Entity Count
 
| VarInt
 
| Number of elements in the following array.
 
|-
 
| Entities
 
| Array of String (32767)
 
| Identifiers for the removed entities.  For players, this is their username; for other entities, it is their UUID.
 
 
  |}
 
  |}
  
Team Color: The color of a team defines how the names of the team members are visualized; any formatting code can be used. The following table lists all the possible values.
+
==== Set Equipment ====
  
 
{| class="wikitable"
 
{| class="wikitable"
  ! ID
+
  ! Packet ID
  ! Formatting
+
  ! State
 +
! Bound To
 +
! colspan="2"| Field Name
 +
! colspan="2"| Field Type
 +
! Notes
 
  |-
 
  |-
  | 0-15
+
  | rowspan="3"| 0x5B
  | Color formatting, same values as [[Chat]] colors.
+
| rowspan="3"| Play
 +
| rowspan="3"| Client
 +
| colspan="2"| Entity ID
 +
| colspan="2"| {{Type|VarInt}}
 +
| Entity's ID.
 +
|-
 +
  | rowspan="2"| Equipment
 +
| Slot
 +
| rowspan="2"| {{Type|Array}}
 +
| {{Type|Byte}} {{Type|Enum}}
 +
| Equipment slot (see below).  Also has the top bit set if another entry follows, and otherwise unset if this is the last item in the array.
 
  |-
 
  |-
  | 16
+
  | Item
  | Obfuscated
+
  | {{Type|Slot}}
 +
|
 +
|}
 +
 
 +
Equipment slot can be one of the following:
 +
 
 +
{| class="wikitable"
 +
! ID
 +
! Equipment slot
 +
|-
 +
| 0
 +
| Main hand
 +
|-
 +
| 1
 +
| Off hand
 
  |-
 
  |-
  | 17
+
  | 2
  | Bold
+
  | Boots
 
  |-
 
  |-
  | 18
+
  | 3
  | Strikethrough
+
  | Leggings
 
  |-
 
  |-
  | 19
+
  | 4
  | Underlined
+
  | Chestplate
 
  |-
 
  |-
  | 20
+
  | 5
  | Italic
+
  | Helmet
 
  |-
 
  |-
  | 21
+
  | 6
  | Reset
+
  | Body
 
  |}
 
  |}
  
==== Update Score ====
+
==== Set Experience ====
  
This is sent to the client when it should update a scoreboard item.
+
Sent by the server when the client should change experience levels.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 5,671: Line 6,147:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="4"| 0x5D
+
  | rowspan="3"| 0x5C
  | rowspan="4"| Play
+
  | rowspan="3"| Play
  | rowspan="4"| Client
+
  | rowspan="3"| Client
  | Entity Name
+
  | Experience bar
  | String (32767)
+
  | {{Type|Float}}
  | The entity whose score this is.  For players, this is their username; for other entities, it is their UUID.
+
  | Between 0 and 1.
 
  |-
 
  |-
  | Action
+
  | Level
  | VarInt Enum
+
  | {{Type|VarInt}}
  | 0 to create/update an item. 1 to remove an item.
+
  |
 
  |-
 
  |-
  | Objective Name
+
  | Total Experience
  | String (32767)
+
  | {{Type|VarInt}}
| The name of the objective the score belongs to.
+
  | See {{Minecraft Wiki|Experience#Leveling up}} on the Minecraft Wiki for Total Experience to Level conversion.
  |-
 
| Value
 
| Optional VarInt
 
| The score to be displayed next to the entry. Only sent when Action does not equal 1.
 
 
  |}
 
  |}
  
==== Set Simulation Distance ====
+
==== Set Health ====
 +
 
 +
Sent by the server to set the health of the player it is sent to.
 +
 
 +
Food {{Minecraft Wiki|Food#Hunger and saturation|saturation}} acts as a food “overcharge”. Food values will not decrease while the saturation is over zero. New players logging in or respawning automatically get a saturation of 5.0. Eating food increases the saturation as well as the food bar.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 5,701: Line 6,177:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | 0x5E
+
  | rowspan="3"| 0x5D
  | Play
+
  | rowspan="3"| Play
  | Client
+
  | rowspan="3"| Client
  | Simulation Distance
+
  | Health
  | VarInt
+
| {{Type|Float}}
  | The distance that the client will process specific things, such as entities.
+
| 0 or less = dead, 20 = full HP.
 +
|-
 +
| Food
 +
  | {{Type|VarInt}}
 +
| 0–20.
 +
|-
 +
| Food Saturation
 +
| {{Type|Float}}
 +
  | Seems to vary from 0.0 to 5.0 in integer increments.
 
  |}
 
  |}
  
==== Set Subtitle Text ====
+
==== Update Objectives ====
 +
 
 +
This is sent to the client when it should create a new {{Minecraft Wiki|scoreboard}} objective or remove one.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 5,715: Line 6,201:
 
  ! State
 
  ! State
 
  ! Bound To
 
  ! Bound To
  ! Field Name
+
  ! colspan="2"| Field Name
 
  ! Field Type
 
  ! Field Type
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="1"| 0x5F
+
  | rowspan="10"| 0x5E
  | rowspan="1"| Play
+
  | rowspan="10"| Play
  | rowspan="1"| Client
+
  | rowspan="10"| Client
  | Subtitle Text
+
| colspan="2"| Objective Name
  | [[Chat]]
+
| {{Type|String}} (32767)
  |
+
| A unique name for the objective.
 +
|-
 +
| colspan="2"| Mode
 +
| {{Type|Byte}}
 +
| 0 to create the scoreboard. 1 to remove the scoreboard. 2 to update the display text.
 +
|-
 +
| colspan="2"| Objective Value
 +
  | {{Type|Optional}} {{Type|Text Component}}
 +
| Only if mode is 0 or 2.The text to be displayed for the score.
 +
|-
 +
| colspan="2"| Type
 +
| {{Type|Optional}} {{Type|VarInt}} {{Type|Enum}}
 +
| Only if mode is 0 or 2. 0 = "integer", 1 = "hearts".
 +
|-
 +
| colspan="2"| Has Number Format
 +
| {{Type|Optional}} {{Type|Boolean}}
 +
| Only if mode is 0 or 2. Whether this objective has a set number format for the scores.
 +
|-
 +
| colspan="2"| Number Format
 +
| {{Type|Optional}} {{Type|VarInt}} {{Type|Enum}}
 +
| Only if mode is 0 or 2 and the previous boolean is true. Determines how the score number should be formatted.
 +
|-
 +
! Number Format
 +
! Field Name
 +
!
 +
!
 +
|-
 +
| 0: blank
 +
| colspan="2"| ''no fields''
 +
| Show nothing.
 +
|-
 +
| 1: styled
 +
| Styling
 +
  | [[NBT#Specification:compound_tag|Compound Tag]]
 +
  | The styling to be used when formatting the score number. Contains the [[Text formatting#Styling fields|text component styling fields]].
 +
|-
 +
| 2: fixed
 +
| Content
 +
| {{Type|Text Component}}
 +
| The text to be used as placeholder.
 
  |}
 
  |}
  
==== Update Time ====
+
==== Set Passengers ====
 
 
Time is based on ticks, where 20 ticks happen every second. There are 24000 ticks in a day, making Minecraft days exactly 20 minutes long.
 
 
 
The time of day is based on the timestamp modulo 24000. 0 is sunrise, 6000 is noon, 12000 is sunset, and 18000 is midnight.
 
 
 
The default SMP server increments the time by <code>20</code> every second.
 
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 5,743: Line 6,262:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="2"| 0x60
+
  | rowspan="3"| 0x5F
  | rowspan="2"| Play
+
  | rowspan="3"| Play
  | rowspan="2"| Client
+
  | rowspan="3"| Client
  | World Age
+
  | Entity ID
  | Long
+
  | {{Type|VarInt}}
  | In ticks; not changed by server commands.
+
| Vehicle's EID.
 +
|-
 +
| Passenger Count
 +
| {{Type|VarInt}}
 +
  | Number of elements in the following array.
 
  |-
 
  |-
  | Time of day
+
  | Passengers
  | Long
+
  | {{Type|Array}} of {{Type|VarInt}}
  | The world (or region) time, in ticks. If negative the sun will stop moving at the Math.abs of the time.
+
  | EIDs of entity's passengers.
 
  |}
 
  |}
  
==== Set Title Text ====
+
==== Update Teams ====
 +
 
 +
Creates and updates teams.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 5,761: Line 6,286:
 
  ! State
 
  ! State
 
  ! Bound To
 
  ! Bound To
  ! Field Name
+
  ! colspan="2"| Field Name
 
  ! Field Type
 
  ! Field Type
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="1"| 0x61
+
  | rowspan="23"| 0x60
  | rowspan="1"| Play
+
  | rowspan="23"| Play
  | rowspan="1"| Client
+
  | rowspan="23"| Client
  | Title Text
+
  | colspan="2"| Team Name
  | [[Chat]]
+
| {{Type|String}} (32767)
 +
| A unique name for the team. (Shared with scoreboard).
 +
|-
 +
| colspan="2"| Method
 +
| {{Type|Byte}}
 +
| Determines the layout of the remaining packet.
 +
|-
 +
| rowspan="9"| 0: create team
 +
| Team Display Name
 +
  | {{Type|Text Component}}
 
  |
 
  |
|}
 
 
==== Set Title Animation Times ====
 
 
{| class="wikitable"
 
! Packet ID
 
! State
 
! Bound To
 
! Field Name
 
! Field Type
 
! Notes
 
 
  |-
 
  |-
  | rowspan="3"| 0x62
+
  | Friendly Flags
  | rowspan="3"| Play
+
  | {{Type|Byte}}
  | rowspan="3"| Client
+
  | Bit mask. 0x01: Allow friendly fire, 0x02: can see invisible players on same team.
  | Fade In
+
|-
  | Int
+
  | Name Tag Visibility
  | Ticks to spend fading in.
+
  | {{Type|String}} {{Type|Enum}} (40)
 +
  | <code>always</code>, <code>hideForOtherTeams</code>, <code>hideForOwnTeam</code>, <code>never</code>.
 
  |-
 
  |-
  | Stay
+
  | Collision Rule
  | Int
+
  | {{Type|String}} {{Type|Enum}} (40)
  | Ticks to keep the title displayed.
+
  | <code>always</code>, <code>pushOtherTeams</code>, <code>pushOwnTeam</code>, <code>never</code>.
 
  |-
 
  |-
  | Fade Out
+
  | Team Color
  | Int
+
  | {{Type|VarInt}} {{Type|Enum}}
| Ticks to spend fading out, not when to start fading out.
+
| Used to color the name of players on the team; see below.
|}
 
 
 
==== Entity Sound Effect ====
 
 
 
Plays a sound effect from an entity, either by hardcoded ID or Identifier. Sound IDs and names can be found [https://pokechu22.github.io/Burger/1.20.1.html#sounds here].
 
 
 
{{Warning|Numeric sound effect IDs are liable to change between versions}}
 
 
 
{| class="wikitable"
 
! Packet ID
 
! State
 
! Bound To
 
! Field Name
 
! Field Type
 
! Notes
 
 
  |-
 
  |-
  | rowspan="9"| 0x63
+
  | Team Prefix
  | rowspan="9"| Play
+
  | {{Type|Text Component}}
  | rowspan="9"| Client
+
  | Displayed before the names of players that are part of this team.
| Sound ID
 
| VarInt
 
| Represents the <code>Sound ID + 1</code>. If the value is 0, the packet contains a sound specified by Identifier.
 
 
  |-
 
  |-
  | Sound Name
+
  | Team Suffix
  | Optional Identifier
+
  | {{Type|Text Component}}
  | Only present if Sound ID is 0
+
  | Displayed after the names of players that are part of this team.
 
  |-
 
  |-
  | Has Fixed Range
+
  | Entity Count
  | Optional Boolean
+
  | {{Type|VarInt}}
  | Only present if Sound ID is 0.
+
  | Number of elements in the following array.
 
  |-
 
  |-
  | Range
+
  | Entities
  | Optional Float
+
  | {{Type|Array}} of {{Type|String}} (32767)
  | The fixed range of the sound. Only present if previous boolean is true and Sound ID is 0.
+
  | Identifiers for the entities in this team. For players, this is their username; for other entities, it is their UUID.
 
  |-
 
  |-
  | Sound Category
+
  | 1: remove team
  | VarInt Enum
+
  | ''no fields''
  | The category that this sound will be played from ([https://gist.github.com/konwboj/7c0c380d3923443e9d55 current categories]).
+
| ''no fields''
 +
  |
 
  |-
 
  |-
  | Entity ID
+
  | rowspan="7"| 2: update team info
  | VarInt
+
  | Team Display Name
 +
| {{Type|Text Component}}
 
  |
 
  |
 
  |-
 
  |-
  | Volume
+
  | Friendly Flags
  | Float
+
  | {{Type|Byte}}
  | 1.0 is 100%, capped between 0.0 and 1.0 by Notchian clients.
+
  | Bit mask. 0x01: Allow friendly fire, 0x02: can see invisible entities on same team.
 +
|-
 +
| Name Tag Visibility
 +
| {{Type|String}} {{Type|Enum}} (40)
 +
| <code>always</code>, <code>hideForOtherTeams</code>, <code>hideForOwnTeam</code>, <code>never</code>
 
  |-
 
  |-
  | Pitch
+
  | Collision Rule
  | Float
+
  | {{Type|String}} {{Type|Enum}} (40)
  | Float between 0.5 and 2.0 by Notchian clients.
+
  | <code>always</code>, <code>pushOtherTeams</code>, <code>pushOwnTeam</code>, <code>never</code>
 
  |-
 
  |-
  | Seed
+
  | Team Color
  | Long
+
  | {{Type|VarInt}} {{Type|Enum}}
  | Seed used to pick sound variant.
+
  | Used to color the name of players on the team; see below.
  |}
+
|-
 
+
| Team Prefix
==== Sound Effect ====
+
| {{Type|Text Component}}
 +
| Displayed before the names of players that are part of this team.
 +
  |-
 +
| Team Suffix
 +
| {{Type|Text Component}}
 +
| Displayed after the names of players that are part of this team.
 +
|-
 +
| rowspan="2"| 3: add entities to team
 +
| Entity Count
 +
| {{Type|VarInt}}
 +
| Number of elements in the following array.
 +
|-
 +
| Entities
 +
| {{Type|Array}} of {{Type|String}} (32767)
 +
| Identifiers for the added entities.  For players, this is their username; for other entities, it is their UUID.
 +
|-
 +
| rowspan="2"| 4: remove entities from team
 +
| Entity Count
 +
| {{Type|VarInt}}
 +
| Number of elements in the following array.
 +
|-
 +
| Entities
 +
| {{Type|Array}} of {{Type|String}} (32767)
 +
| Identifiers for the removed entities.  For players, this is their username; for other entities, it is their UUID.
 +
|}
 +
 
 +
Team Color: The color of a team defines how the names of the team members are visualized; any formatting code can be used. The following table lists all the possible values.
 +
 
 +
{| class="wikitable"
 +
! ID
 +
! Formatting
 +
|-
 +
| 0-15
 +
| Color formatting, same values as in [[Text formatting#Colors]].
 +
|-
 +
| 16
 +
| Obfuscated
 +
|-
 +
| 17
 +
| Bold
 +
|-
 +
| 18
 +
| Strikethrough
 +
|-
 +
| 19
 +
| Underlined
 +
|-
 +
| 20
 +
| Italic
 +
|-
 +
| 21
 +
| Reset
 +
|}
  
Plays a sound effect at the given location, either by hardcoded ID or Identifier. Sound IDs and names can be found [https://pokechu22.github.io/Burger/1.20.1.html#sounds here].
+
==== Update Score ====
  
{{Warning|Numeric sound effect IDs are liable to change between versions}}
+
This is sent to the client when it should update a scoreboard item.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 5,863: Line 6,427:
 
  ! State
 
  ! State
 
  ! Bound To
 
  ! Bound To
  ! Field Name
+
  ! colspan="2"| Field Name
 
  ! Field Type
 
  ! Field Type
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="11"| 0x64
+
  | rowspan="11"| 0x61
 
  | rowspan="11"| Play
 
  | rowspan="11"| Play
 
  | rowspan="11"| Client
 
  | rowspan="11"| Client
  | Sound ID
+
  | colspan="2"| Entity Name
  | VarInt
+
  | {{Type|String}} (32767)
  | Represents the <code>Sound ID + 1</code>. If the value is 0, the packet contains a sound specified by Identifier.
+
  | The entity whose score this is. For players, this is their username; for other entities, it is their UUID.
 
  |-
 
  |-
  | Sound Name
+
  | colspan="2"| Objective Name
  | Optional Identifier
+
  | {{Type|String}} (32767)
  | Only present if Sound ID is 0
+
  | The name of the objective the score belongs to.
 
  |-
 
  |-
  | Has Fixed Range
+
  | colspan="2"| Value
  | Optional Boolean
+
  | {{Type|VarInt}}
  | Only present if Sound ID is 0.
+
  | The score to be displayed next to the entry.
 
  |-
 
  |-
  | Range
+
  | colspan="2"| Has Display Name
  | Optional Float
+
  | {{Type|Boolean}}
  | The fixed range of the sound. Only present if previous boolean is true and Sound ID is 0.
+
  | Whether this score has a custom display name.
 
  |-
 
  |-
  | Sound Category
+
  | colspan="2"| Display Name
  | VarInt Enum
+
  | {{Type|Optional}} {{Type|Text Component}}
  | The category that this sound will be played from ([https://gist.github.com/konwboj/7c0c380d3923443e9d55 current categories]).
+
  | The custom display name. Only present if the previous boolean is true.
 
  |-
 
  |-
  | Effect Position X
+
  | colspan="2"| Has Number Format
  | Int
+
  | {{Type|Boolean}}
  | Effect X multiplied by 8 ([[Data types#Fixed-point numbers|fixed-point number]] with only 3 bits dedicated to the fractional part).
+
  | Whether this score has a set number format. This overrides the number format set on the objective, if any.
 
  |-
 
  |-
  | Effect Position Y
+
  | colspan="2"| Number Format
  | Int
+
  | {{Type|Optional}} {{Type|VarInt}} {{Type|Enum}}
  | Effect Y multiplied by 8 ([[Data types#Fixed-point numbers|fixed-point number]] with only 3 bits dedicated to the fractional part).
+
  | Determines how the score number should be formatted. Only present if the previous boolean is true.
 
  |-
 
  |-
  | Effect Position Z
+
  ! Number Format
  | Int
+
  ! Field Name
  | Effect Z multiplied by 8 ([[Data types#Fixed-point numbers|fixed-point number]] with only 3 bits dedicated to the fractional part).
+
  !
 +
!
 
  |-
 
  |-
  | Volume
+
  | 0: blank
  | Float
+
  | colspan="2"| ''no fields''
  | 1.0 is 100%, capped between 0.0 and 1.0 by Notchian clients.
+
  | Show nothing.
 
  |-
 
  |-
  | Pitch
+
  | 1: styled
  | Float
+
  | Styling
  | Float between 0.5 and 2.0 by Notchian clients.
+
  | [[NBT#Specification:compound_tag|Compound Tag]]
 +
| The styling to be used when formatting the score number. Contains the [[Text formatting#Styling fields|text component styling fields]].
 
  |-
 
  |-
  | Seed
+
  | 2: fixed
  | Long
+
  | Content
  | Seed used to pick sound variant.
+
  | {{Type|Text Component}}
 +
| The text to be used as placeholder.
 
  |}
 
  |}
  
==== Start Configuration ====
+
==== Set Simulation Distance ====
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 +
|-
 +
| 0x62
 +
| Play
 +
| Client
 +
| Simulation Distance
 +
| {{Type|VarInt}}
 +
| The distance that the client will process specific things, such as entities.
 +
|}
  
Sent during gameplay in order to redo the configuration process. The client must respond with [[#Acknowledge Configuration|Acknowledge Configuration]] for the process to start.
+
==== Set Subtitle Text ====
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 5,927: Line 6,510:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="1"| 0x65
+
  | rowspan="1"| 0x63
 
  | rowspan="1"| Play
 
  | rowspan="1"| Play
 
  | rowspan="1"| Client
 
  | rowspan="1"| Client
  | colspan="3"| ''no fields''
+
  | Subtitle Text
 +
| {{Type|Text Component}}
 +
|
 
  |}
 
  |}
  
This packet switches the connection state to [[#Configuration|configuration]].
+
==== Update Time ====
 +
 
 +
Time is based on ticks, where 20 ticks happen every second. There are 24000 ticks in a day, making Minecraft days exactly 20 minutes long.
 +
 
 +
The time of day is based on the timestamp modulo 24000. 0 is sunrise, 6000 is noon, 12000 is sunset, and 18000 is midnight.
  
==== Stop Sound ====
+
The default SMP server increments the time by <code>20</code> every second.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 5,945: Line 6,534:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="3"| 0x66
+
  | rowspan="2"| 0x64
  | rowspan="3"| Play
+
  | rowspan="2"| Play
  | rowspan="3"| Client
+
  | rowspan="2"| Client
  | Flags
+
  | World Age
  | Byte
+
  | {{Type|Long}}
  | Controls which fields are present.
+
  | In ticks; not changed by server commands.
 
  |-
 
  |-
  | Source
+
  | Time of day
  | Optional VarInt Enum
+
  | {{Type|Long}}
  | Only if flags is 3 or 1 (bit mask 0x1). See below. If not present, then sounds from all sources are cleared.
+
  | The world (or region) time, in ticks. If negative the sun will stop moving at the Math.abs of the time.
|-
 
| Sound
 
| Optional Identifier
 
| Only if flags is 2 or 3 (bit mask 0x2).  A sound effect name, see [[#Custom Sound Effect|Custom Sound Effect]]. If not present, then all sounds are cleared.
 
 
  |}
 
  |}
  
Categories:
+
==== Set Title Text ====
  
 
{| class="wikitable"
 
{| class="wikitable"
  ! Name !! Value
+
  ! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 
  |-
 
  |-
  | master || 0
+
  | rowspan="1"| 0x65
|-
+
  | rowspan="1"| Play
  | music || 1
+
  | rowspan="1"| Client
|-
+
  | Title Text
  | record || 2
+
  | {{Type|Text Component}}
  |-
+
  |
  | weather || 3
 
  |-
 
| block || 4
 
|-
 
| hostile || 5
 
|-
 
| neutral || 6
 
|-
 
| player || 7
 
|-
 
| ambient || 8
 
|-
 
| voice || 9
 
 
  |}
 
  |}
  
==== System Chat Message ====
+
==== Set Title Animation Times ====
 
 
Sends the client a raw system message.
 
 
 
Identifying the difference between Chat/System Message is important as it helps respect the user's chat visibility options. See [[Chat#Processing chat|processing chat]] for more info about these positions.
 
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 6,001: Line 6,574:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="2"| 0x67
+
  | rowspan="3"| 0x66
  | rowspan="2"| Play
+
  | rowspan="3"| Play
  | rowspan="2"| Client
+
  | rowspan="3"| Client
  | Content
+
  | Fade In
  | [[Chat]]
+
  | {{Type|Int}}
  | Limited to 262144 bytes.
+
| Ticks to spend fading in.
 +
|-
 +
| Stay
 +
| {{Type|Int}}
 +
  | Ticks to keep the title displayed.
 
  |-
 
  |-
  | Overlay
+
  | Fade Out
  | Boolean
+
  | {{Type|Int}}
  | Whether the message is an actionbar or chat message.
+
  | Ticks to spend fading out, not when to start fading out.
 
  |}
 
  |}
  
==== Set Tab List Header And Footer ====
+
==== Entity Sound Effect ====
 +
 
 +
Plays a sound effect from an entity, either by hardcoded ID or Identifier. Sound IDs and names can be found [https://pokechu22.github.io/Burger/1.21.html#sounds here].
  
This packet may be used by custom servers to display additional information above/below the player list. It is never sent by the Notchian server.
+
{{Warning|Numeric sound effect IDs are liable to change between versions}}
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 6,025: Line 6,604:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="2"| 0x68
+
  | rowspan="9"| 0x67
  | rowspan="2"| Play
+
  | rowspan="9"| Play
  | rowspan="2"| Client
+
  | rowspan="9"| Client
  | Header
+
  | Sound ID
  | [[Chat]]
+
  | {{Type|VarInt}}
  | To remove the header, send a empty text component: <code>{"text":""}</code>.
+
  | Represents the <code>Sound ID + 1</code>. If the value is 0, the packet contains a sound specified by Identifier.
 +
|-
 +
| Sound Name
 +
| {{Type|Optional}} {{Type|Identifier}}
 +
| Only present if Sound ID is 0
 +
|-
 +
| Has Fixed Range
 +
| {{Type|Optional}} {{Type|Boolean}}
 +
| Only present if Sound ID is 0.
 +
|-
 +
| Range
 +
| {{Type|Optional}} {{Type|Float}}
 +
| The fixed range of the sound. Only present if previous boolean is true and Sound ID is 0.
 +
|-
 +
| Sound Category
 +
| {{Type|VarInt}} {{Type|Enum}}
 +
| The category that this sound will be played from ([https://gist.github.com/konwboj/7c0c380d3923443e9d55 current categories]).
 +
|-
 +
| Entity ID
 +
| {{Type|VarInt}}
 +
|
 +
|-
 +
| Volume
 +
| {{Type|Float}}
 +
| 1.0 is 100%, capped between 0.0 and 1.0 by Notchian clients.
 +
|-
 +
| Pitch
 +
| {{Type|Float}}
 +
| Float between 0.5 and 2.0 by Notchian clients.
 
  |-
 
  |-
  | Footer
+
  | Seed
  | [[Chat]]
+
  | {{Type|Long}}
  | To remove the footer, send a empty text component: <code>{"text":""}</code>.
+
  | Seed used to pick sound variant.
 
  |}
 
  |}
  
==== Tag Query Response ====
+
==== Sound Effect ====
 +
 
 +
Plays a sound effect at the given location, either by hardcoded ID or Identifier. Sound IDs and names can be found [https://pokechu22.github.io/Burger/1.21.html#sounds here].
  
Sent in response to [[#Query Block Entity Tag|Query Block Entity Tag]] or [[#Query Entity Tag|Query Entity Tag]].
+
{{Warning|Numeric sound effect IDs are liable to change between versions}}
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 6,049: Line 6,658:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="2"| 0x69
+
  | rowspan="11"| 0x68
  | rowspan="2"| Play
+
  | rowspan="11"| Play
  | rowspan="2"| Client
+
  | rowspan="11"| Client
  | Transaction ID
+
  | Sound ID
  | VarInt
+
| {{Type|VarInt}}
  | Can be compared to the one sent in the original query packet.
+
| Represents the <code>Sound ID + 1</code>. If the value is 0, the packet contains a sound specified by Identifier.
 +
|-
 +
| Sound Name
 +
| {{Type|Optional}} {{Type|Identifier}}
 +
| Only present if Sound ID is 0
 +
|-
 +
| Has Fixed Range
 +
| {{Type|Optional}} {{Type|Boolean}}
 +
| Only present if Sound ID is 0.
 +
|-
 +
| Range
 +
| {{Type|Optional}} {{Type|Float}}
 +
| The fixed range of the sound. Only present if previous boolean is true and Sound ID is 0.
 +
|-
 +
  | Sound Category
 +
| {{Type|VarInt}} {{Type|Enum}}
 +
  | The category that this sound will be played from ([https://gist.github.com/konwboj/7c0c380d3923443e9d55 current categories]).
 +
|-
 +
| Effect Position X
 +
| {{Type|Int}}
 +
| Effect X multiplied by 8 ([[Data types#Fixed-point numbers|fixed-point number]] with only 3 bits dedicated to the fractional part).
 +
|-
 +
| Effect Position Y
 +
| {{Type|Int}}
 +
| Effect Y multiplied by 8 ([[Data types#Fixed-point numbers|fixed-point number]] with only 3 bits dedicated to the fractional part).
 +
|-
 +
| Effect Position Z
 +
| {{Type|Int}}
 +
| Effect Z multiplied by 8 ([[Data types#Fixed-point numbers|fixed-point number]] with only 3 bits dedicated to the fractional part).
 +
|-
 +
| Volume
 +
| {{Type|Float}}
 +
| 1.0 is 100%, capped between 0.0 and 1.0 by Notchian clients.
 +
|-
 +
| Pitch
 +
| {{Type|Float}}
 +
| Float between 0.5 and 2.0 by Notchian clients.
 
  |-
 
  |-
  | NBT
+
  | Seed
  | [[NBT|NBT Tag]]
+
  | {{Type|Long}}
  | The NBT of the block or entity.  May be a TAG_END (0) in which case no NBT is present.
+
  | Seed used to pick sound variant.
 
  |}
 
  |}
  
==== Pickup Item ====
+
==== Start Configuration ====
  
Sent by the server when someone picks up an item lying on the ground — its sole purpose appears to be the animation of the item flying towards you. It doesn't destroy the entity in the client memory, and it doesn't add it to your inventory. The server only checks for items to be picked up after each [[#Set Player Position|Set Player Position]] (and [[#Set Player Position And Rotation|Set Player Position And Rotation]]) packet sent by the client. The collector entity can be any entity; it does not have to be a player. The collected entity also can be any entity, but the Notchian server only uses this for items, experience orbs, and the different varieties of arrows.
+
Sent during gameplay in order to redo the configuration process. The client must respond with [[#Acknowledge Configuration|Acknowledge Configuration]] for the process to start.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 6,073: Line 6,718:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="3"| 0x6A
+
  | rowspan="1"| 0x69
  | rowspan="3"| Play
+
  | rowspan="1"| Play
  | rowspan="3"| Client
+
  | rowspan="1"| Client
  | Collected Entity ID
+
  | colspan="3"| ''no fields''
| VarInt
 
|
 
|-
 
| Collector Entity ID
 
| VarInt
 
|
 
|-
 
| Pickup Item Count
 
| VarInt
 
| Seems to be 1 for XP orbs, otherwise the number of items in the stack.
 
 
  |}
 
  |}
  
==== Teleport Entity ====
+
This packet switches the connection state to [[#Configuration|configuration]].
  
This packet is sent by the server when an entity moves more than 8 blocks.
+
==== Stop Sound ====
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 6,101: Line 6,736:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="7"| 0x6B
+
  | rowspan="3"| 0x6A
  | rowspan="7"| Play
+
  | rowspan="3"| Play
  | rowspan="7"| Client
+
  | rowspan="3"| Client
  | Entity ID
+
  | Flags
  | VarInt
+
  | {{Type|Byte}}
  |
+
| Controls which fields are present.
 +
|-
 +
| Source
 +
| {{Type|Optional}} {{Type|VarInt}} {{Type|Enum}}
 +
  | Only if flags is 3 or 1 (bit mask 0x1). See below. If not present, then sounds from all sources are cleared.
 +
|-
 +
| Sound
 +
| {{Type|Optional}} {{Type|Identifier}}
 +
| Only if flags is 2 or 3 (bit mask 0x2).  A sound effect name, see [[#Custom Sound Effect|Custom Sound Effect]]. If not present, then all sounds are cleared.
 +
|}
 +
 
 +
Categories:
 +
 
 +
{| class="wikitable"
 +
! Name !! Value
 +
|-
 +
| master || 0
 +
|-
 +
| music || 1
 +
|-
 +
| record || 2
 +
|-
 +
| weather || 3
 
  |-
 
  |-
  | X
+
  | block || 4
| Double
 
|
 
 
  |-
 
  |-
  | Y
+
  | hostile || 5
| Double
 
|
 
 
  |-
 
  |-
  | Z
+
  | neutral || 6
| Double
 
|
 
 
  |-
 
  |-
  | Yaw
+
  | player || 7
| Angle
 
| (Y Rot)New angle, not a delta.
 
 
  |-
 
  |-
  | Pitch
+
  | ambient || 8
| Angle
 
| (X Rot)New angle, not a delta.
 
 
  |-
 
  |-
  | On Ground
+
  | voice || 9
| Boolean
 
|
 
 
  |}
 
  |}
  
==== Update Advancements ====
+
==== Store Cookie (play) ====
 +
 
 +
Stores some arbitrary data on the client, which persists between server transfers. The Notchian client only accepts cookies of up to 5 kiB in size.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 6,143: Line 6,790:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="9"| 0x6C
+
  | rowspan="3"| 0x6B
  | rowspan="9"| Play
+
  | rowspan="3"| Play
  | rowspan="9"| Client
+
  | rowspan="3"| Client
  | colspan="2"| Reset/Clear
+
  | colspan="2"| Key
  | colspan="2"| Boolean
+
  | colspan="2"| {{Type|Identifier}}
  | Whether to reset/clear the current advancements.
+
| The identifier of the cookie.
 +
|-
 +
| colspan="2"| Payload Length
 +
| colspan="2"| {{Type|VarInt}}
 +
  | Length of the following byte array.
 
  |-
 
  |-
  | colspan="2"| Mapping size
+
  | colspan="2"| Payload
  | colspan="2"| VarInt
+
  | colspan="2"| {{Type|Byte Array}} (5120)
  | Size of the following array.
+
  | The data of the cookie.
 +
|}
 +
 
 +
==== System Chat Message ====
 +
 
 +
{{Main|Chat}}
 +
 
 +
Sends the client a raw system message.
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 
  |-
 
  |-
  | rowspan="2"| Advancement mapping
+
  | rowspan="2"| 0x6C
  | Key
+
  | rowspan="2"| Play
  | rowspan="2"| Array
+
  | rowspan="2"| Client
  | Identifier
+
  | Content
  | The identifier of the advancement.
+
| {{Type|Text Component}}
 +
  | Limited to 262144 bytes.
 
  |-
 
  |-
  | Value
+
  | Overlay
  | Advancement
+
  | {{Type|Boolean}}
| See below
+
  | Whether the message is an actionbar or chat message. See also [[#Set Action Bar Text]].
|-
 
| colspan="2"| List size
 
| colspan="2"| VarInt
 
| Size of the following array.
 
|-
 
| colspan="2"| Identifiers
 
| colspan="2"| Array of Identifier
 
| The identifiers of the advancements that should be removed.
 
|-
 
| colspan="2"| Progress size
 
| colspan="2"| VarInt
 
| Size of the following array.
 
|-
 
| rowspan="2"| Progress mapping
 
| Key
 
| rowspan="2"| Array
 
  | Identifier
 
| The identifier of the advancement.
 
|-
 
| Value
 
| Advancement progress
 
| See below.
 
 
  |}
 
  |}
  
Advancement structure:
+
==== Set Tab List Header And Footer ====
 +
 
 +
This packet may be used by custom servers to display additional information above/below the player list. It is never sent by the Notchian server.
  
 
{| class="wikitable"
 
{| class="wikitable"
  ! colspan="2"| Field Name
+
  ! Packet ID
  ! colspan="2"| Field Type
+
! State
 +
! Bound To
 +
! Field Name
 +
  ! Field Type
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | colspan="2"| Has parent
+
  | rowspan="2"| 0x6D
  | colspan="2"| Boolean
+
  | rowspan="2"| Play
  | Indicates whether the next field exists.
+
  | rowspan="2"| Client
 +
| Header
 +
| {{Type|Text Component}}
 +
| To remove the header, send a empty text component: <code>{"text":""}</code>.
 
  |-
 
  |-
  | colspan="2"| Parent id
+
  | Footer
| colspan="2"| Optional Identifier
+
| {{Type|Text Component}}
  | The identifier of the parent advancement.
+
| To remove the footer, send a empty text component: <code>{"text":""}</code>.
 +
|}
 +
 
 +
==== Tag Query Response ====
 +
 
 +
Sent in response to [[#Query Block Entity Tag|Query Block Entity Tag]] or [[#Query Entity Tag|Query Entity Tag]].
 +
 
 +
{| class="wikitable"
 +
  ! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 
  |-
 
  |-
  | colspan="2"| Has display
+
  | rowspan="2"| 0x6E
  | colspan="2"| Boolean
+
  | rowspan="2"| Play
  | Indicates whether the next field exists.
+
  | rowspan="2"| Client
 +
| Transaction ID
 +
| {{Type|VarInt}}
 +
| Can be compared to the one sent in the original query packet.
 
  |-
 
  |-
  | colspan="2"| Display data
+
  | NBT
  | colspan="2"| Optional advancement display
+
  | {{Type|NBT}}
  | See below.
+
  | The NBT of the block or entityMay be a TAG_END (0) in which case no NBT is present.
|-
 
| colspan="2"| Array length
 
| colspan="2"| VarInt
 
| Number of arrays in the following array.
 
|-
 
| rowspan="2"| Requirements
 
| Array length 2
 
| rowspan="2"| Array
 
| VarInt
 
| Number of elements in the following array.
 
  |-
 
| Requirement
 
| Array of String (32767)
 
| Array of required criteria.
 
|-
 
| colspan="2"| Sends telemetry data
 
| colspan="2"| Boolean
 
| Whether the client should include this achievement in the telemetry data when it's completed.
 
The Notchian client only sends data for advancements on the <code>minecraft</code> namespace.
 
 
  |}
 
  |}
  
Advancement display:
+
==== Pickup Item ====
 +
 
 +
Sent by the server when someone picks up an item lying on the ground — its sole purpose appears to be the animation of the item flying towards you. It doesn't destroy the entity in the client memory, and it doesn't add it to your inventory. The server only checks for items to be picked up after each [[#Set Player Position|Set Player Position]] (and [[#Set Player Position And Rotation|Set Player Position And Rotation]]) packet sent by the client. The collector entity can be any entity; it does not have to be a player. The collected entity also can be any entity, but the Notchian server only uses this for items, experience orbs, and the different varieties of arrows.
  
 
{| class="wikitable"
 
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 
  ! Field Name
 
  ! Field Name
 
  ! Field Type
 
  ! Field Type
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | Title
+
  | rowspan="3"| 0x6F
  | Chat
+
| rowspan="3"| Play
 +
| rowspan="3"| Client
 +
| Collected Entity ID
 +
| {{Type|VarInt}}
 +
  |
 +
|-
 +
| Collector Entity ID
 +
| {{Type|VarInt}}
 
  |
 
  |
 
  |-
 
  |-
  | Description
+
  | Pickup Item Count
  | Chat
+
  | {{Type|VarInt}}
 +
| Seems to be 1 for XP orbs, otherwise the number of items in the stack.
 +
|}
 +
 
 +
==== Teleport Entity ====
 +
 
 +
This packet is sent by the server when an entity moves more than 8 blocks.
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 +
|-
 +
| rowspan="7"| 0x70
 +
| rowspan="7"| Play
 +
| rowspan="7"| Client
 +
| Entity ID
 +
| {{Type|VarInt}}
 
  |
 
  |
 
  |-
 
  |-
  | Icon
+
  | X
  | [[Slot]]
+
  | {{Type|Double}}
 
  |
 
  |
 
  |-
 
  |-
  | Frame type
+
  | Y
  | VarInt Enum
+
  | {{Type|Double}}
  | 0 = <code>task</code>, 1 = <code>challenge</code>, 2 = <code>goal</code>.
+
  |
 
  |-
 
  |-
  | Flags
+
  | Z
  | Int
+
  | {{Type|Double}}
  | 0x01: has background texture; 0x02: <code>show_toast</code>; 0x04: <code>hidden</code>.
+
  |
 
  |-
 
  |-
  | Background texture
+
  | Yaw
  | Optional Identifier
+
  | {{Type|Angle}}
  | Background texture location.  Only if flags indicates it.
+
  | (Y Rot)New angle, not a delta.
 
  |-
 
  |-
  | X coord
+
  | Pitch
  | Float
+
  | {{Type|Angle}}
  |
+
  | (X Rot)New angle, not a delta.
 
  |-
 
  |-
  | Y coord
+
  | On Ground
  | Float
+
  | {{Type|Boolean}}
 
  |
 
  |
 
  |}
 
  |}
  
Advancement progress:
+
==== Set Ticking State ====
 +
 
 +
Used to adjust the ticking rate of the client, and whether it's frozen.
  
 
{| class="wikitable"
 
{| class="wikitable"
  ! colspan="2"| Field Name
+
  ! Packet ID
  ! colspan="2"| Field Type
+
! State
 +
! Bound To
 +
! Field Name
 +
  ! Field Type
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | colspan="2"| Size
+
  | rowspan="2" | 0x71
  | colspan="2"| VarInt
+
  | rowspan="2" | Play
| Size of the following array.
+
  | rowspan="2" | Client
|-
+
  | Tick rate
  | rowspan="2"| Criteria
+
  | {{Type|Float}}
  | Criterion identifier
+
  |
  | rowspan="2"| Array
 
| Identifier
 
  | The identifier of the criterion.
 
 
  |-
 
  |-
  | Criterion progress
+
  | Is frozen
  | Criterion progress
+
  | {{Type|Boolean}}
 
  |
 
  |
 
  |}
 
  |}
  
Criterion progress:
+
==== Step Tick ====
 +
 
 +
Advances the client processing by the specified number of ticks. Has no effect unless client ticking is frozen.
  
 
{| class="wikitable"
 
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 
  ! Field Name
 
  ! Field Name
 
  ! Field Type
 
  ! Field Type
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | Achieved
+
  | 0x72
  | Boolean
+
  | Play
  | If true, next field is present.
+
  | Client
  |-
+
  | Tick steps
  | Date of achieving
+
  | {{Type|VarInt}}
| Optional Long
+
  |
  | As returned by [https://docs.oracle.com/javase/6/docs/api/java/util/Date.html#getTime() <code>Date.getTime</code>].
 
 
  |}
 
  |}
  
==== Update Attributes ====
+
==== Transfer (play) ====
  
Sets {{Minecraft Wiki|Attribute|attributes}} on the given entity.
+
Notifies the client that it should transfer to the given server. Cookies previously stored are preserved between server transfers.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 6,320: Line 7,008:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="6"| 0x6D
+
  | rowspan="2"| 0x73
  | rowspan="6"| Play
+
  | rowspan="2"| Play
  | rowspan="6"| Client
+
  | rowspan="2"| Client
  | colspan="2"| Entity ID
+
  | colspan="2"| Host
  | colspan="2"| VarInt
+
  | colspan="2"| {{Type|String}}
  |
+
  | The hostname of IP of the server.
 
  |-
 
  |-
  | colspan="2"| Number Of Properties
+
  | colspan="2"| Port
  | colspan="2"| VarInt
+
  | colspan="2"| {{Type|VarInt}}
| Number of elements in the following array.
+
  | The port of the server.
|-
 
| rowspan="4"| Property
 
| Key
 
| rowspan="4"| Array
 
| Identifier
 
| See below.
 
|-
 
| Value
 
| Double
 
| See below.
 
|-
 
| Number Of Modifiers
 
| VarInt
 
  | Number of elements in the following array.
 
|-
 
| Modifiers
 
| Array of Modifier Data
 
| See {{Minecraft Wiki|Attribute#Modifiers}}. Modifier Data defined below.
 
 
  |}
 
  |}
  
Known Key values (see also {{Minecraft Wiki|Attribute#Modifiers}}):
+
==== Update Advancements ====
  
 
{| class="wikitable"
 
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! colspan="2"| Field Name
 +
! colspan="2"| Field Type
 +
! Notes
 
  |-
 
  |-
  ! Key
+
  | rowspan="9"| 0x74
  ! Default
+
  | rowspan="9"| Play
  ! Min
+
  | rowspan="9"| Client
  ! Max
+
  | colspan="2"| Reset/Clear
  ! Label
+
  | colspan="2"| {{Type|Boolean}}
 +
| Whether to reset/clear the current advancements.
 
  |-
 
  |-
  | generic.max_health
+
  | colspan="2"| Mapping size
  | 20.0
+
  | colspan="2"| {{Type|VarInt}}
| 1.0
+
  | Size of the following array.
| 1024.0
 
  | Max Health.
 
 
  |-
 
  |-
  | generic.follow_range
+
  | rowspan="2"| Advancement mapping
  | 32.0
+
  | Key
  | 0.0
+
  | rowspan="2"| {{Type|Array}}
  | 2048.0
+
  | {{Type|Identifier}}
  | Follow Range.
+
  | The identifier of the advancement.
 
  |-
 
  |-
  | generic.knockback_resistance
+
  | Value
  | 0.0
+
  | Advancement
  | 0.0
+
  | See below
| 1.0
 
| Knockback Resistance.
 
 
  |-
 
  |-
  | generic.movement_speed
+
  | colspan="2"| List size
  | 0.7
+
  | colspan="2"| {{Type|VarInt}}
| 0.0
+
  | Size of the following array.
| 1024.0
 
  | Movement Speed.
 
 
  |-
 
  |-
  | generic.flying_speed
+
  | colspan="2"| Identifiers
  | 0.4
+
  | colspan="2"| {{Type|Array}} of {{Type|Identifier}}
| 0.0
+
  | The identifiers of the advancements that should be removed.
| 1024.0
 
  | Flying Speed.
 
 
  |-
 
  |-
  | generic.attack_damage
+
  | colspan="2"| Progress size
  | 2.0
+
  | colspan="2"| {{Type|VarInt}}
| 0.0
+
  | Size of the following array.
| 2048.0
 
  | Attack Damage.
 
 
  |-
 
  |-
  | generic.attack_knockback
+
  | rowspan="2"| Progress mapping
  | 0.0
+
  | Key
  | 0.0
+
  | rowspan="2"| {{Type|Array}}
  | 5.0
+
  | {{Type|Identifier}}
  | &mdash;
+
  | The identifier of the advancement.
 
  |-
 
  |-
  | generic.attack_speed
+
  | Value
  | 4.0
+
| Advancement progress
  | 0.0
+
  | See below.
  | 1024.0
+
  |}
  | Attack Speed.
+
 
 +
Advancement structure:
 +
 
 +
{| class="wikitable"
 +
  ! colspan="2"| Field Name
 +
  ! colspan="2"| Field Type
 +
! Notes
 
  |-
 
  |-
  | generic.armor
+
  | colspan="2"| Has parent
  | 0.0
+
  | colspan="2"| {{Type|Boolean}}
| 0.0
+
  | Indicates whether the next field exists.
| 30.0
 
  | Armor.
 
 
  |-
 
  |-
  | generic.armor_toughness
+
  | colspan="2"| Parent id
  | 0.0
+
  | colspan="2"| {{Type|Optional}} {{Type|Identifier}}
| 0.0
+
  | The identifier of the parent advancement.
| 20.0
 
  | Armor Toughness.
 
 
  |-
 
  |-
  | generic.luck
+
  | colspan="2"| Has display
  | 0.0
+
  | colspan="2"| {{Type|Boolean}}
| -1024.0
+
  | Indicates whether the next field exists.
| 1024.0
 
  | Luck.
 
 
  |-
 
  |-
  | zombie.spawn_reinforcements
+
  | colspan="2"| Display data
  | 0.0
+
  | colspan="2"| {{Type|Optional}} Advancement display
| 0.0
+
  | See below.
| 1.0
 
  | Spawn Reinforcements Chance.
 
 
  |-
 
  |-
  | horse.jump_strength
+
  | colspan="2"| Array length
  | 0.7
+
  | colspan="2"| {{Type|VarInt}}
| 0.0
+
  | Number of arrays in the following array.
| 2.0
 
  | Jump Strength.
 
 
  |-
 
  |-
  | generic.reachDistance
+
  | rowspan="2"| Requirements
  | 5.0
+
  | Array length 2
  | 0.0
+
  | rowspan="2"| {{Type|Array}}
  | 1024.0
+
  | {{Type|VarInt}}
  | Player Reach Distance (Forge only).
+
  | Number of elements in the following array.
 
  |-
 
  |-
  | forge.swimSpeed
+
  | Requirement
  | 1.0
+
| {{Type|Array}} of {{Type|String}} (32767)
  | 0.0
+
| Array of required criteria.
  | 1024.0
+
  |-
  | Swimming Speed (Forge only).
+
  | colspan="2"| Sends telemetry data
 +
  | colspan="2"| {{Type|Boolean}}
 +
  | Whether the client should include this achievement in the telemetry data when it's completed.
 +
The Notchian client only sends data for advancements on the <code>minecraft</code> namespace.
 
  |}
 
  |}
  
''Modifier Data'' structure:
+
Advancement display:
  
 
{| class="wikitable"
 
{| class="wikitable"
|-
 
 
  ! Field Name
 
  ! Field Name
 
  ! Field Type
 
  ! Field Type
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | UUID
+
  | Title
  | UUID
+
  | {{Type|Text Component}}
 +
|
 +
|-
 +
| Description
 +
| {{Type|Text Component}}
 +
|
 +
|-
 +
| Icon
 +
| {{Type|Slot}}
 
  |
 
  |
 
  |-
 
  |-
  | Amount
+
  | Frame type
  | Double
+
  | {{Type|VarInt}} {{Type|Enum}}
  | May be positive or negative.
+
| 0 = <code>task</code>, 1 = <code>challenge</code>, 2 = <code>goal</code>.
 +
|-
 +
| Flags
 +
| {{Type|Int}}
 +
| 0x01: has background texture; 0x02: <code>show_toast</code>; 0x04: <code>hidden</code>.
 +
|-
 +
| Background texture
 +
| {{Type|Optional}} {{Type|Identifier}}
 +
  | Background texture location.  Only if flags indicates it.
 +
|-
 +
| X coord
 +
| {{Type|Float}}
 +
|
 
  |-
 
  |-
  | Operation
+
  | Y coord
  | Byte
+
  | {{Type|Float}}
  | See below.
+
  |
 
  |}
 
  |}
  
The operation controls how the base value of the modifier is changed.
+
Advancement progress:
 
 
* 0: Add/subtract amount
 
* 1: Add/subtract amount percent of the current value
 
* 2: Multiply by amount percent
 
 
 
All of the 0's are applied first, and then the 1's, and then the 2's.
 
 
 
==== Entity Effect ====
 
  
 
{| class="wikitable"
 
{| class="wikitable"
  ! Packet ID
+
  ! colspan="2"| Field Name
! State
+
  ! colspan="2"| Field Type
! Bound To
 
! Field Name
 
  ! Field Type
 
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="7"| 0x6E
+
  | colspan="2"| Size
  | rowspan="7"| Play
+
  | colspan="2"| {{Type|VarInt}}
| rowspan="7"| Client
+
  | Size of the following array.
| Entity ID
 
| VarInt
 
  |
 
 
  |-
 
  |-
  | Effect ID
+
  | rowspan="2"| Criteria
  | VarInt
+
  | Criterion identifier
  | See {{Minecraft Wiki|Status effect#Effect list|this table}}.
+
  | rowspan="2"| {{Type|Array}}
 +
| {{Type|Identifier}}
 +
| The identifier of the criterion.
 
  |-
 
  |-
  | Amplifier
+
  | Criterion progress
  | Byte
+
  | Criterion progress
  | Notchian client displays effect level as Amplifier + 1.
+
  |
|-
 
| Duration
 
| VarInt
 
| Duration in ticks.
 
|-
 
| Flags
 
| Byte
 
| Bit field, see below.
 
|-
 
| Has Factor Data
 
| Boolean
 
| Used in DARKNESS effect
 
|-
 
| Factor Codec
 
| NBT Tag
 
| See below
 
 
  |}
 
  |}
  
Within flags:
+
Criterion progress:
 
 
* 0x01: Is ambient - was the effect spawned from a beacon?  All beacon-generated effects are ambient.  Ambient effects use a different icon in the HUD (blue border rather than gray).  If all effects on an entity are ambient, the [[Entity_metadata#Living Entity|"Is potion effect ambient" living metadata field]] should be set to true.  Usually should not be enabled.
 
* 0x02: Show particles - should all particles from this effect be hidden?  Effects with particles hidden are not included in the calculation of the effect color, and are not rendered on the HUD (but are still rendered within the inventory).  Usually should be enabled.
 
* 0x04: Show icon - should the icon be displayed on the client?  Usually should be enabled.
 
  
Factor Data
 
 
{| class="wikitable"
 
{| class="wikitable"
  !Name
+
  ! Field Name
  !Type
+
  ! Field Type
  !style="width: 250px;" colspan="2"| Notes
+
  ! Notes
 
  |-
 
  |-
  | padding_duration
+
  | Achieved
  | TAG_INT
+
  | {{Type|Boolean}}
  |
+
  | If true, next field is present.
 
  |-
 
  |-
  | factor_start
+
  | Date of achieving
  | TAG_FLOAT
+
  | {{Type|Optional}} {{Type|Long}}
|
+
  | As returned by [https://docs.oracle.com/javase/6/docs/api/java/util/Date.html#getTime() <code>Date.getTime</code>].
|-
 
| factor_target
 
| TAG_FLOAT
 
|
 
|-
 
| factor_current
 
| TAG_FLOAT
 
|
 
|-
 
| effect_changed_timestamp
 
| TAG_INT
 
|-
 
| factor_previous_frame
 
| TAG_FLOAT
 
|-
 
| had_effect_last_tick
 
  | TAG_BOOLEAN
 
 
  |}
 
  |}
  
==== Update Recipes ====
+
==== Update Attributes ====
 +
 
 +
Sets {{Minecraft Wiki|Attribute|attributes}} on the given entity.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 6,570: Line 7,207:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="4"| 0x6F
+
  | rowspan="6"| 0x75
  | rowspan="4"| Play
+
  | rowspan="6"| Play
  | rowspan="4"| Client
+
  | rowspan="6"| Client
  | colspan="2"| Num Recipes
+
  | colspan="2"| Entity ID
  | colspan="2"| VarInt
+
  | colspan="2"| {{Type|VarInt}}
 +
|
 +
|-
 +
| colspan="2"| Number Of Properties
 +
| colspan="2"| {{Type|VarInt}}
 
  | Number of elements in the following array.
 
  | Number of elements in the following array.
 
  |-
 
  |-
  | rowspan="3"| Recipe
+
  | rowspan="4"| Property
  | Type
+
  | Id
  | rowspan="3"| Array
+
  | rowspan="4"| {{Type|Array}}
  | Identifier
+
  | {{Type|VarInt}} {{Type|Enum}}
  | The recipe type, see below.
+
| See below.
 +
|-
 +
| Value
 +
| {{Type|Double}}
 +
  | See below.
 
  |-
 
  |-
  | Recipe ID
+
  | Number Of Modifiers
  | Identifier
+
  | {{Type|VarInt}}
  |
+
  | Number of elements in the following array.
 
  |-
 
  |-
  | Data
+
  | Modifiers
  | Varies
+
  | {{Type|Array}} of Modifier Data
  | Additional data for the recipe.
+
  | See {{Minecraft Wiki|Attribute#Modifiers}}. Modifier Data defined below.
 
  |}
 
  |}
  
Recipe types:
+
Known Id values (see also {{Minecraft Wiki|Attribute#Modifiers}}):
  
 
{| class="wikitable"
 
{| class="wikitable"
! Type
 
! Description
 
! Data
 
 
  |-
 
  |-
  | <code>minecraft:crafting_shapeless</code>
+
  ! Id
  | Shapeless crafting recipe. All items in the ingredient list must be present, but in any order/slot.
+
  ! Key
  | As follows:
+
  ! Default
  {| class="wikitable"
+
! Min
    ! Name
+
! Max
    ! Type
+
! Label
    ! Description
 
    |-
 
    | Group
 
    | String (32767)
 
    | Used to group similar recipes together in the recipe book. Tag is present in recipe JSON.
 
    |-
 
    |Category
 
    |VarInt Enum
 
    |Building = 0, Redstone = 1, Equipment = 2, Misc = 3
 
    |-
 
    | Ingredient count
 
    | VarInt
 
    | Number of elements in the following array.
 
    |-
 
    | Ingredients
 
    | Array of Ingredient.
 
    |
 
    |-
 
    | Result
 
    | [[Slot]]
 
    |
 
    |}
 
 
  |-
 
  |-
  | <code>minecraft:crafting_shaped</code>
+
  | 0
  | Shaped crafting recipe. All items must be present in the same pattern (which may be flipped horizontally or translated).
+
  | generic.armor
  | As follows:
+
  | 0.0
  {| class="wikitable"
+
| 0.0
    ! Name
+
| 30.0
    ! Type
+
| Armor.
    ! Description
 
    |-
 
    | Width
 
    | VarInt
 
    |
 
    |-
 
    | Height
 
    | VarInt
 
    |
 
    |-
 
    | Group
 
    | String (32767)
 
    | Used to group similar recipes together in the recipe book. Tag is present in recipe JSON.
 
    |-
 
    |Category
 
    |VarInt Enum
 
    |Building = 0, Redstone = 1, Equipment = 2, Misc = 3
 
    |-
 
    | Ingredients
 
    | Array of Ingredient
 
    | Length is <code>width * height</code>. Indexed by <code>x + (y * width)</code>.
 
    |-
 
    | Result
 
    | [[Slot]]
 
    |-
 
    | Show notification
 
    | Boolean
 
    | Show a toast when the recipe is [[Protocol#Update_Recipe_Book|added]].
 
    |}
 
 
  |-
 
  |-
  | <code>minecraft:crafting_special_armordye</code>
+
  | 1
  | Recipe for dying leather armor
+
  | generic.armor_toughness
  | rowspan="14" | As follows:
+
  | 0.0
  {| class="wikitable"
+
| 0.0
    ! Name
+
| 20.0
    ! Type
+
| Armor Toughness.
    ! Description
 
    |-
 
    |Category
 
    |VarInt Enum
 
    |Building = 0, Redstone = 1, Equipment = 2, Misc = 3
 
    |}
 
 
  |-
 
  |-
  | <code>minecraft:crafting_special_bookcloning</code>
+
  | 2
  | Recipe for copying contents of written books
+
  | generic.attack_damage
 +
| 2.0
 +
| 0.0
 +
| 2048.0
 +
| Attack Damage.
 
  |-
 
  |-
  | <code>minecraft:crafting_special_mapcloning</code>
+
  | 3
  | Recipe for copying maps
+
  | generic.attack_knockback
 +
| 0.0
 +
| 0.0
 +
| 5.0
 +
| Attack Knockback.
 
  |-
 
  |-
  | <code>minecraft:crafting_special_mapextending</code>
+
  | 4
  | Recipe for adding paper to maps
+
  | generic.attack_speed
 +
| 4.0
 +
| 0.0
 +
| 1024.0
 +
| Attack Speed.
 
  |-
 
  |-
  | <code>minecraft:crafting_special_firework_rocket</code>
+
  | 5
  | Recipe for making firework rockets
+
  | generic.block_break_speed
 +
| 1.0
 +
| 0.0
 +
| 1024.0
 +
| Block Break Speed.
 
  |-
 
  |-
  | <code>minecraft:crafting_special_firework_star</code>
+
  | 6
  | Recipe for making firework stars
+
  | generic.block_interaction_range
 +
| 4.5
 +
| 0.0
 +
| 64.0
 +
| Block Interaction Range.
 
  |-
 
  |-
  | <code>minecraft:crafting_special_firework_star_fade</code>
+
  | 7
  | Recipe for making firework stars fade between multiple colors
+
  | generic.entity_interaction_range
 +
| 3.0
 +
| 0.0
 +
| 64.0
 +
| Entity Interaction Range.
 
  |-
 
  |-
  | <code>minecraft:crafting_special_repairitem</code>
+
  | 8
  | Recipe for repairing items via crafting
+
  | generic.fall_damage_multiplier
 +
| 1.0
 +
| 0.0
 +
| 100.0
 +
| Fall Damage Multiplier.
 
  |-
 
  |-
  | <code>minecraft:crafting_special_tippedarrow</code>
+
  | 9
  | Recipe for crafting tipped arrows
+
  | generic.flying_speed
 +
| 0.4
 +
| 0.0
 +
| 1024.0
 +
| Flying Speed.
 
  |-
 
  |-
  | <code>minecraft:crafting_special_bannerduplicate</code>
+
  | 10
  | Recipe for copying banner patterns
+
  | generic.follow_range
 +
| 32.0
 +
| 0.0
 +
| 2048.0
 +
| Follow Range.
 
  |-
 
  |-
  | <code>minecraft:crafting_special_shielddecoration</code>
+
  | 11
  | Recipe for applying a banner's pattern to a shield
+
  | generic.gravity
 +
| 0.08
 +
| -1.0
 +
| 1.0
 +
| Gravity.
 
  |-
 
  |-
  | <code>minecraft:crafting_special_shulkerboxcoloring</code>
+
  | 12
  | Recipe for recoloring a shulker box
+
  | generic.jump_strength
 +
| 0.42
 +
| 0.0
 +
| 32.0
 +
| Jump Strength.
 
  |-
 
  |-
  | <code>minecraft:crafting_special_suspiciousstew</code>
+
  | 13
  | Recipe for crafting suspicious stews
+
  | generic.knockback_resistance
 +
| 0.0
 +
| 0.0
 +
| 1.0
 +
| Knockback Resistance.
 
  |-
 
  |-
  | <code>minecraft:crafting_decorated_pot</code>
+
  | 14
  | Recipe for crafting decorated pots
+
  | generic.luck
 +
| 0.0
 +
| -1024.0
 +
| 1024.0
 +
| Luck.
 
  |-
 
  |-
  | <code>minecraft:smelting</code>
+
  | 15
  | Smelting recipe
+
  | generic.max_absorption
  | rowspan="4"| As follows:
+
  | 0.0
  {| class="wikitable"
+
| 0.0
    ! Name
+
| 2048.0
    ! Type
+
| Max Absorption.
    ! Description
 
    |-
 
    | Group
 
    | String (32767)
 
    | Used to group similar recipes together in the recipe book.
 
    |-
 
    |Category
 
    |VarInt Enum
 
    |Food = 0, Blocks = 1, Misc = 2
 
    |-
 
    | Ingredient
 
    | Ingredient
 
    |
 
    |-
 
    | Result
 
    | [[Slot]]
 
    |
 
    |-
 
    | Experience
 
    | Float
 
    |
 
    |-
 
    | Cooking time
 
    | VarInt
 
    |
 
    |}
 
 
  |-
 
  |-
  | <code>minecraft:blasting</code>
+
  | 16
  | Blast furnace recipe
+
  | generic.max_health
 +
| 20.0
 +
| 1.0
 +
| 1024.0
 +
| Max Health.
 
  |-
 
  |-
  | <code>minecraft:smoking</code>
+
  | 17
  | Smoker recipe
+
  | generic.movement_speed
  |-
+
  | 0.7
  | <code>minecraft:campfire_cooking</code>
+
  | 0.0
  | Campfire recipe
+
  | 1024.0
 +
| Movement Speed.
 
  |-
 
  |-
  | <code>minecraft:stonecutting</code>
+
  | 18
  | Stonecutter recipe
+
  | generic.safe_fall_distance
  | As follows:
+
  | 3.0
  {| class="wikitable"
+
| -1024.0
    ! Name
+
| 1024.0
    ! Type
+
| Safe Fall Distance.
    ! Description
 
    |-
 
    | Group
 
    | String (32767)
 
    | Used to group similar recipes together in the recipe book. Tag is present in recipe JSON.
 
    |-
 
    | Ingredient
 
    | Ingredient
 
    |
 
    |-
 
    | Result
 
    | [[Slot]]
 
    |
 
    |}
 
 
  |-
 
  |-
  | <code>minecraft:smithing_transform</code>
+
  | 19
  | Recipe for smithing netherite gear
+
  | generic.scale
  | As follows:
+
  | 1.0
  {| class="wikitable"
+
| 0.0625
    ! Name
+
| 16.0
    ! Type
+
| Scale.
    ! Description
 
    |-
 
    | Template
 
    | Ingredient
 
    | The smithing template.
 
    |-
 
    | Base
 
    | Ingredient
 
    | The base item.
 
    |-
 
    | Addition
 
    | Ingredient
 
    | The additional ingredient.
 
    |-
 
    | Result
 
    | [[Slot]]
 
    |
 
    |}
 
 
  |-
 
  |-
  | <code>minecraft:smithing_trim</code>
+
  | 20
  | Recipe for applying armor trims
+
  | zombie.spawn_reinforcements
  | As follows:
+
| 0.0
  {| class="wikitable"
+
  | 0.0
    ! Name
+
| 1.0
    ! Type
+
| Spawn Reinforcements Chance.
    ! Description
+
|-
    |-
+
| 21
    | Template
+
| generic.step_height
    | Ingredient
+
| 0.6
    | The smithing template.
+
| 0.0
    |-
+
| 10.0
    | Base
+
| Step Height.
    | Ingredient
+
|-
    | The base item.
+
| 22
    |-
+
| generic.submerged_mining_speed
    | Addition
+
| 0.2
    | Ingredient
+
| 0.0
    | The additional ingredient.
+
| 20.0
    |}
+
| Submerged Mining Speed.
 +
|-
 +
| 23
 +
| generic.sweeping_damage_ratio
 +
| 0.0
 +
| 0.0
 +
| 1.0
 +
| Sweeping Damage Ratio.
 +
|-
 +
| 24
 +
| generic.water_movement_efficiency
 +
| 0.0
 +
| 0.0
 +
| 1.0
 +
| Water Movement Efficiency.
 
  |}
 
  |}
  
Ingredient is defined as:
+
''Modifier Data'' structure:
  
 
{| class="wikitable"
 
{| class="wikitable"
! Name
 
! Type
 
! Description
 
 
  |-
 
  |-
  | Count
+
! Field Name
  | VarInt
+
! Field Type
  | Number of elements in the following array.
+
! Notes
 +
|-
 +
  | Id
 +
  | {{Type|Identifier}}
 +
|
 +
|-
 +
| Amount
 +
| {{Type|Double}}
 +
  | May be positive or negative.
 
  |-
 
  |-
  | Items
+
  | Operation
  | Array of [[Slot]]
+
  | {{Type|Byte}}
  | Any item in this array may be used for the recipe.  The count of each item should be 1.
+
  | See below.
 
  |}
 
  |}
  
==== Update Tags ====
+
The operation controls how the base value of the modifier is changed.
 +
 
 +
* 0: Add/subtract amount
 +
* 1: Add/subtract amount percent of the current value
 +
* 2: Multiply by amount percent
 +
 
 +
All of the 0's are applied first, and then the 1's, and then the 2's.
 +
 
 +
==== Entity Effect ====
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 6,848: Line 7,459:
 
  ! State
 
  ! State
 
  ! Bound To
 
  ! Bound To
  ! colspan="2"| Field Name
+
  ! Field Name
  ! colspan="2"| Field Type
+
  ! Field Type
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="3"| 0x70
+
  | rowspan="5"| 0x76
  | rowspan="3"| Play
+
  | rowspan="5"| Play
  | rowspan="3"| Client
+
  | rowspan="5"| Client
  | colspan="2"| Length of the array
+
  | Entity ID
  | colspan="2"| VarInt
+
  | {{Type|VarInt}}
 
  |
 
  |
 
  |-
 
  |-
  | rowspan="2"| Array of tags
+
  | Effect ID
  | Tag type
+
  | {{Type|VarInt}}
  | rowspan="2"| Array
+
  | See {{Minecraft Wiki|Status effect#Effect list|this table}}.
| Identifier
 
| Tag identifier (Vanilla required tags are <code>minecraft:block</code>, <code>minecraft:item</code>, <code>minecraft:fluid</code>, <code>minecraft:entity_type</code>, and <code>minecraft:game_event</code>)
 
 
  |-
 
  |-
  | Array of Tag
+
  | Amplifier
  | (See below)
+
  | {{Type|VarInt}}
|
+
  | Notchian client displays effect level as Amplifier + 1.
|}
 
 
 
Tags look like:
 
 
 
{| class="wikitable"
 
! colspan="2"| Field Name
 
  ! colspan="2"| Field Type
 
! Notes
 
 
  |-
 
  |-
  | colspan="2"| Length
+
  | Duration
  | colspan="2"| VarInt
+
  | {{Type|VarInt}}
  | Number of elements in the following array
+
  | Duration in ticks. (-1 for infinite)
 
  |-
 
  |-
  | rowspan="3"| Tags
+
  | Flags
| Tag name
+
  | {{Type|Byte}}
| rowspan="3"| Array
+
  | Bit field, see below.
| Identifier
 
|
 
|-
 
| Count
 
| VarInt
 
| Number of elements in the following array
 
|-
 
  | Entries
 
| Array of VarInt
 
  | Numeric ID of the given type (block, item, etc.).
 
 
  |}
 
  |}
  
More information on tags is available at: https://minecraft.wiki/w/Tag
+
{{Need Info|What exact effect does the blend bit flag have on the client? What happens if it is used on effects besides DARKNESS?}}
  
And a list of all tags is here: https://minecraft.wiki/w/Tag#List_of_tags
+
Within flags:
  
=== Serverbound ===
+
* 0x01: Is ambient - was the effect spawned from a beacon?  All beacon-generated effects are ambient.  Ambient effects use a different icon in the HUD (blue border rather than gray).  If all effects on an entity are ambient, the [[Entity_metadata#Living Entity|"Is potion effect ambient" living metadata field]] should be set to true.  Usually should not be enabled.
 +
* 0x02: Show particles - should all particles from this effect be hidden?  Effects with particles hidden are not included in the calculation of the effect color, and are not rendered on the HUD (but are still rendered within the inventory).  Usually should be enabled.
 +
* 0x04: Show icon - should the icon be displayed on the client?  Usually should be enabled.
 +
* 0x08: Blend - should the effect's hard-coded blending be applied?  Currently only used in the DARKNESS effect to apply extra void fog and adjust the gamma value for lighting.
  
==== Confirm Teleportation ====
 
  
Sent by client as confirmation of [[#Synchronize Player Position|Synchronize Player Position]].
+
==== Update Recipes ====
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 6,910: Line 7,503:
 
  ! State
 
  ! State
 
  ! Bound To
 
  ! Bound To
  ! Field Name
+
  ! colspan="2"| Field Name
  ! Field Type
+
  ! colspan="2"| Field Type
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | 0x00
+
  | rowspan="4"| 0x77
  | Play
+
  | rowspan="4"| Play
  | Server
+
  | rowspan="4"| Client
  | Teleport ID
+
  | colspan="2"| Num Recipes
  | VarInt
+
  | colspan="2"| {{Type|VarInt}}
  | The ID given by the [[#Synchronize Player Position|Synchronize Player Position]] packet.
+
  | Number of elements in the following array.
  |}
+
  |-
 
+
| rowspan="3"| Recipe
==== Query Block Entity Tag ====
+
  | Recipe ID
 
+
  | rowspan="3"| {{Type|Array}}
Used when <kbd>F3</kbd>+<kbd>I</kbd> is pressed while looking at a block.
+
  | {{Type|Identifier}}
 
+
  |
{| class="wikitable"
 
  ! Packet ID
 
  ! State
 
  ! Bound To
 
! Field Name
 
! Field Type
 
  ! Notes
 
 
  |-
 
  |-
  | rowspan="2"| 0x01
+
  | Type ID
  | rowspan="2"| Play
+
  | {{Type|VarInt}} {{Type|Enum}}
| rowspan="2"| Server
+
  | The recipe type, see below.
  | Transaction ID
 
| VarInt
 
| An incremental ID so that the client can verify that the response matches.
 
 
  |-
 
  |-
  | Location
+
  | Data
  | Position
+
  | Varies
  | The location of the block to check.
+
  | Additional data for the recipe.
 
  |}
 
  |}
  
==== Change Difficulty ====
+
Recipe types:
 
 
Must have at least op level 2 to use.  Appears to only be used on singleplayer; the difficulty buttons are still disabled in multiplayer.
 
  
 
{| class="wikitable"
 
{| class="wikitable"
  ! Packet ID
+
  ! ID
  ! State
+
  ! Type
! Bound To
+
  ! Description
! Field Name
+
  ! Data
  ! Field Type
 
  ! Notes
 
 
  |-
 
  |-
  | 0x02
+
  | 0
  | Play
+
  | <code>minecraft:crafting_shaped</code>
  | Server
+
  | Shaped crafting recipe. All items must be present in the same pattern (which may be flipped horizontally or translated).
  | New difficulty
+
  | As follows:
| Byte
+
  {| class="wikitable"
| 0: peaceful, 1: easy, 2: normal, 3: hard .
+
    ! Name
|}
+
    ! Type
 
+
    ! Description
==== Acknowledge Message ====
+
    |-
 
+
    | Group
{| class="wikitable"
+
    | {{Type|String}} (32767)
! Packet ID
+
    | Used to group similar recipes together in the recipe book. Tag is present in recipe JSON.
! State
+
    |-
! Bound To
+
    |Category
! Field Name
+
    |{{Type|VarInt}} {{Type|Enum}}
! Field Type
+
    |Building = 0, Redstone = 1, Equipment = 2, Misc = 3
! Notes
+
    |-
 +
    | Width
 +
    | {{Type|VarInt}}
 +
    |
 +
    |-
 +
    | Height
 +
    | {{Type|VarInt}}
 +
    |
 +
    |-
 +
    | Ingredients
 +
    | {{Type|Array}} of Ingredient
 +
    | Length is <code>width * height</code>. Indexed by <code>x + (y * width)</code>.
 +
    |-
 +
    | Result
 +
    | {{Type|Slot}}
 +
    |-
 +
    | Show notification
 +
    | {{Type|Boolean}}
 +
    | Show a toast when the recipe is [[Protocol#Update_Recipe_Book|added]].
 +
    |}
 
  |-
 
  |-
  | rowspan="1"| 0x03
+
  | 1
  | rowspan="1"| Play
+
| <code>minecraft:crafting_shapeless</code>
| rowspan="1"| Server
+
| Shapeless crafting recipe. All items in the ingredient list must be present, but in any order/slot.
| Message Count
+
  | As follows:
| VarInt
+
  {| class="wikitable"
|  
+
    ! Name
|}
+
    ! Type
 
+
    ! Description
==== Chat Command ====
+
    |-
 
+
    | Group
{| class="wikitable"
+
    | {{Type|String}} (32767)
! Packet ID
+
    | Used to group similar recipes together in the recipe book. Tag is present in recipe JSON.
! State
+
    |-
! Bound To
+
    |Category
! colspan="2"| Field Name
+
    |{{Type|VarInt}} {{Type|Enum}}
! colspan="2"| Field Type
+
    |Building = 0, Redstone = 1, Equipment = 2, Misc = 3
! Notes
+
    |-
 +
    | Ingredient count
 +
    | {{Type|VarInt}}
 +
    | Number of elements in the following array.
 +
    |-
 +
    | Ingredients
 +
    | {{Type|Array}} of Ingredient.
 +
    |
 +
    |-
 +
    | Result
 +
    | {{Type|Slot}}
 +
    |
 +
    |}
 
  |-
 
  |-
  | rowspan="8"| 0x04
+
  | 2
  | rowspan="8"| Play
+
| <code>minecraft:crafting_special_armordye</code>
  | rowspan="8"| Server
+
  | Recipe for dying leather armor
| colspan="2"| Command
+
  | rowspan="14" | As follows:
| colspan="2"| String (256)
+
  {| class="wikitable"
| colspan="2"| The command typed by the client.
+
    ! Name
 +
    ! Type
 +
    ! Description
 +
    |-
 +
    |Category
 +
    |{{Type|VarInt}} {{Type|Enum}}
 +
    |Building = 0, Redstone = 1, Equipment = 2, Misc = 3
 +
    |}
 
  |-
 
  |-
  | colspan="2"| Timestamp
+
  | 3
  | colspan="2"| Long
+
  | <code>minecraft:crafting_special_bookcloning</code>
  | colspan="2"| The timestamp that the command was executed.
+
  | Recipe for copying contents of written books
 
  |-
 
  |-
  | colspan="2"| Salt
+
  | 4
  | colspan="2"| Long
+
  | <code>minecraft:crafting_special_mapcloning</code>
  | colspan="2"| The salt for the following argument signatures.
+
  | Recipe for copying maps
 
  |-
 
  |-
  | colspan="2"| Array length
+
  | 5
  | colspan="2"| VarInt
+
  | <code>minecraft:crafting_special_mapextending</code>
  | colspan="2"| Number of entries in the following array. The maximum length in Notchian server is 8.
+
  | Recipe for adding paper to maps
 
  |-
 
  |-
  | rowspan="2"| Array of argument signatures
+
  | 6
| Argument name
+
  | <code>minecraft:crafting_special_firework_rocket</code>
| rowspan="2"| Array (8)
+
  | Recipe for making firework rockets
  | String (16)
 
  | The name of the argument that is signed by the following signature.
 
 
  |-
 
  |-
  | Signature
+
  | 7
  | Byte Array (256)
+
  | <code>minecraft:crafting_special_firework_star</code>
  | The signature that verifies the argument. Always 256 bytes and is not length-prefixed.
+
  | Recipe for making firework stars
 
  |-
 
  |-
  | colspan="2"| Message Count
+
  | 8
  | colspan="2"| VarInt
+
  | <code>minecraft:crafting_special_firework_star_fade</code>
  | colspan="2"|
+
  | Recipe for making firework stars fade between multiple colors
 
  |-
 
  |-
  | colspan="2"| Acknowledged
+
  | 9
  | colspan="2"| Fixed BitSet (20)
+
  | <code>minecraft:crafting_special_tippedarrow</code>
| colspan="2"|
+
  | Recipe for crafting tipped arrows
|}
 
 
 
==== Chat Message ====
 
 
 
Used to send a chat message to the server.  The message may not be longer than 256 characters or else the server will kick the client.
 
 
 
The server will broadcast the same chat message to all players on the server (including the player that sent the message), prepended with player's name.  Specifically, it will respond with a translate [[chat]] component, "<code>chat.type.text</code>" with the first parameter set to the display name of the player (including some chat component logic to support clicking the name to send a PM) and the second parameter set to the message. See [[Chat#Processing chat|processing chat]] for more information.
 
 
 
{| class="wikitable"
 
! Packet ID
 
! State
 
! Bound To
 
! Field Name
 
! Field Type
 
! Notes
 
 
  |-
 
  |-
  | rowspan="7"| 0x05
+
  | 10
| rowspan="7"| Play
+
  | <code>minecraft:crafting_special_bannerduplicate</code>
| rowspan="7"| Server
+
  | Recipe for copying banner patterns
| Message
 
  | String (256)
 
  |
 
 
  |-
 
  |-
  | Timestamp
+
  | 11
  | Long
+
  | <code>minecraft:crafting_special_shielddecoration</code>
  |
+
  | Recipe for applying a banner's pattern to a shield
 
  |-
 
  |-
  | Salt
+
  | 12
  | Long
+
  | <code>minecraft:crafting_special_shulkerboxcoloring</code>
  | The salt used to verify the signature hash.
+
  | Recipe for recoloring a shulker box
 
  |-
 
  |-
  | Has Signature
+
  | 13
  | Boolean
+
  | <code>minecraft:crafting_special_suspiciousstew</code>
  | Whether the next field is present.
+
  | Recipe for crafting suspicious stews
 
  |-
 
  |-
  | Signature
+
  | 14
  | Optional Byte Array (256)
+
  | <code>minecraft:crafting_special_repairitem</code>
  | The signature used to verify the chat message's authentication. When present, always 256 bytes and not length-prefixed.
+
| Recipe for repairing items via crafting
 +
  |-
 +
| 22
 +
| <code>minecraft:crafting_decorated_pot</code>
 +
| Recipe for crafting decorated pots
 
  |-
 
  |-
  | Message Count
+
  | 15
  | VarInt
+
  | <code>minecraft:smelting</code>
|
+
| Smelting recipe
 +
| rowspan="4"| As follows:
 +
  {| class="wikitable"
 +
    ! Name
 +
    ! Type
 +
    ! Description
 +
    |-
 +
    | Group
 +
    | {{Type|String}} (32767)
 +
    | Used to group similar recipes together in the recipe book.
 +
    |-
 +
    |Category
 +
    |{{Type|VarInt}} {{Type|Enum}}
 +
    |Food = 0, Blocks = 1, Misc = 2
 +
    |-
 +
    | Ingredient
 +
    | Ingredient
 +
    |
 +
    |-
 +
    | Result
 +
    | {{Type|Slot}}
 +
    |
 +
    |-
 +
    | Experience
 +
    | {{Type|Float}}
 +
    |
 +
    |-
 +
    | Cooking time
 +
    | {{Type|VarInt}}
 +
    |
 +
    |}
 
  |-
 
  |-
  | Acknowledged
+
  | 16
  | Fixed BitSet (20)
+
  | <code>minecraft:blasting</code>
  |  
+
  | Blast furnace recipe
|}
 
 
 
==== Player Session ====
 
 
 
{| class="wikitable"
 
! Packet ID
 
! State
 
! Bound To
 
! colspan="2"| Field Name
 
! Field Type
 
! Notes
 
 
  |-
 
  |-
  | rowspan="6"| 0x06
+
  | 17
| rowspan="6"| Play
+
  | <code>minecraft:smoking</code>
| rowspan="6"| Server
+
  | Smoker recipe
| colspan="2"| Session Id
 
  | UUID
 
  |
 
 
  |-
 
  |-
  | rowspan="5"| Public Key
+
  | 18
  | Expires At
+
  | <code>minecraft:campfire_cooking</code>
  | Long
+
  | Campfire recipe
| The time the play session key expires in [https://en.wikipedia.org/wiki/Unix_time epoch] milliseconds.
 
 
  |-
 
  |-
  | Public Key Length
+
  | 19
  | VarInt
+
  | <code>minecraft:stonecutting</code>
  | Length of the proceeding public key. Maximum length in Notchian server is 512 bytes.
+
  | Stonecutter recipe
 +
| As follows:
 +
  {| class="wikitable"
 +
    ! Name
 +
    ! Type
 +
    ! Description
 +
    |-
 +
    | Group
 +
    | {{Type|String}} (32767)
 +
    | Used to group similar recipes together in the recipe book. Tag is present in recipe JSON.
 +
    |-
 +
    | Ingredient
 +
    | Ingredient
 +
    |
 +
    |-
 +
    | Result
 +
    | {{Type|Slot}}
 +
    |
 +
    |}
 
  |-
 
  |-
  | Public Key
+
  | 20
  | Byte Array (512)
+
  | <code>minecraft:smithing_transform</code>
  | A byte array of an X.509-encoded public key.
+
| Recipe for smithing netherite gear
|-
+
  | As follows:
| Key Signature Length
+
  {| class="wikitable"
| VarInt
+
    ! Name
| Length of the proceeding key signature array. Maximum length in Notchian server is 4096 bytes.
+
    ! Type
|-
+
    ! Description
  | Key Signature
+
    |-
  | Byte Array (4096)
+
    | Template
  | The signature consists of the player UUID, the key expiration timestamp, and the public key data. These values are hashed using [https://en.wikipedia.org/wiki/SHA-1 SHA-1] and signed using Mojang's private [https://en.wikipedia.org/wiki/RSA_(cryptosystem) RSA] key.
+
    | Ingredient
  |}
+
    | The smithing template.
 
+
    |-
==== Chunk Batch Received ====
+
    | Base
 
+
    | Ingredient
Notifies the server that the chunk batch has been received by the client. The server uses the value sent in this packet to adjust the number of chunks to be sent in a batch.
+
    | The base item.
 +
    |-
 +
    | Addition
 +
    | Ingredient
 +
    | The additional ingredient.
 +
    |-
 +
    | Result
 +
    | {{Type|Slot}}
 +
    |
 +
    |}
 +
  |-
 +
  | 21
 +
  | <code>minecraft:smithing_trim</code>
 +
  | Recipe for applying armor trims
 +
| As follows:
 +
  {| class="wikitable"
 +
    ! Name
 +
    ! Type
 +
    ! Description
 +
    |-
 +
    | Template
 +
    | Ingredient
 +
    | The smithing template.
 +
    |-
 +
    | Base
 +
    | Ingredient
 +
    | The base item.
 +
    |-
 +
    | Addition
 +
    | Ingredient
 +
    | The additional ingredient.
 +
    |}
 +
|}
  
The Notchian server will stop sending further chunk data until the client acknowledges the sent chunk batch. After the first acknowledgement, the server adjusts this number to allow up to 10 unacknowledged batches.
+
Ingredient is defined as:
  
 
{| class="wikitable"
 
{| class="wikitable"
  ! Packet ID
+
  ! Name
  ! State
+
  ! Type
  ! Bound To
+
  ! Description
  ! Field Name
+
|-
  ! Field Type
+
  | Count
  ! Notes
+
  | {{Type|VarInt}}
 +
  | Number of elements in the following array.
 
  |-
 
  |-
  | rowspan="1"| 0x07
+
  | Items
  | rowspan="1"| Play
+
  | {{Type|Array}} of {{Type|Slot}}
| rowspan="1"| Server
+
  | Any item in this array may be used for the recipe. The count of each item should be 1.
  | Chunks per tick
 
  | Float
 
| Desired chunks per tick.
 
 
  |}
 
  |}
  
==== Client Status ====
+
==== Update Tags (play) ====
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 7,145: Line 7,809:
 
  ! State
 
  ! State
 
  ! Bound To
 
  ! Bound To
  ! Field Name
+
  ! colspan="2"| Field Name
  ! Field Type
+
  ! colspan="2"| Field Type
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | 0x08
+
  | rowspan="3"| 0x78
  | Play
+
  | rowspan="3"| Play
  | Server
+
  | rowspan="3"| Client
  | Action ID
+
  | colspan="2"| Length of the array
  | VarInt Enum
+
  | colspan="2"| {{Type|VarInt}}
  | See below
+
|
 +
|-
 +
| rowspan="2"| Array of tags
 +
| Registry
 +
| rowspan="2"| {{Type|Array}}
 +
| {{Type|Identifier}}
 +
| Registry identifier (Vanilla expects tags for the registries <code>minecraft:block</code>, <code>minecraft:item</code>, <code>minecraft:fluid</code>, <code>minecraft:entity_type</code>, and <code>minecraft:game_event</code>)
 +
|-
 +
| Array of Tag
 +
  | (See below)
 +
|
 
  |}
 
  |}
  
''Action ID'' values:
+
Tag arrays look like:
  
 
{| class="wikitable"
 
{| class="wikitable"
 +
! colspan="2"| Field Name
 +
! colspan="2"| Field Type
 +
! Notes
 
  |-
 
  |-
  ! Action ID
+
  | colspan="2"| Length
  ! Action
+
  | colspan="2"| {{Type|VarInt}}
  ! Notes
+
  | Number of elements in the following array
 +
|-
 +
| rowspan="3"| Tags
 +
| Tag name
 +
| rowspan="3"| {{Type|Array}}
 +
| {{Type|Identifier}}
 +
|
 
  |-
 
  |-
  | 0
+
  | Count
  | Perform respawn
+
  | {{Type|VarInt}}
  | Sent when the client is ready to complete login and when the client is ready to respawn after death.
+
  | Number of elements in the following array
 
  |-
 
  |-
  | 1
+
  | Entries
  | Request stats
+
  | {{Type|Array}} of {{Type|VarInt}}
  | Sent when the client opens the Statistics menu.
+
  | Numeric IDs of the given type (block, item, etc.). This list replaces the previous list of IDs for the given tag. If some preexisting tags are left unmentioned, a warning is printed.
 
  |}
 
  |}
  
==== Client Information (play) ====
+
See {{Minecraft Wiki|Tag}} on the Minecraft Wiki for more information, including a list of vanilla tags.
  
Sent when the player connects, or when settings are changed.
+
==== Projectile Power ====
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 7,186: Line 7,869:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="8"| 0x09
+
  | rowspan="2"| 0x79
  | rowspan="8"| Play
+
  | rowspan="2"| Play
  | rowspan="8"| Server
+
  | rowspan="2"| Client
  | Locale
+
  | Entity ID
  | String (16)
+
  | {{Type|VarInt}}
  | e.g. <code>en_GB</code>.
+
  |
 
  |-
 
  |-
  | View Distance
+
  | Power
  | Byte
+
  | {{Type|Double}}
| Client-side render distance, in chunks.
+
  |
|-
+
  |}
| Chat Mode
 
| VarInt Enum
 
| 0: enabled, 1: commands only, 2: hidden.  See [[Chat#Processing chat|processing chat]] for more information.
 
|-
 
| Chat Colors
 
| Boolean
 
| “Colors” multiplayer setting. Can the chat be colored?
 
|-
 
| Displayed Skin Parts
 
| Unsigned Byte
 
| Bit mask, see below.
 
|-
 
| Main Hand
 
| VarInt Enum
 
| 0: Left, 1: Right.
 
|-
 
| Enable text filtering
 
| Boolean
 
| Enables filtering of text on signs and written book titles. Currently always false (i.e. the filtering is disabled)
 
|-
 
| Allow server listings
 
| Boolean
 
  | Servers usually list online players, this option should let you not show up in that list.
 
  |}
 
  
''Displayed Skin Parts'' flags:
+
==== Custom Report Details ====
 
 
* Bit 0 (0x01): Cape enabled
 
* Bit 1 (0x02): Jacket enabled
 
* Bit 2 (0x04): Left Sleeve enabled
 
* Bit 3 (0x08): Right Sleeve enabled
 
* Bit 4 (0x10): Left Pants Leg enabled
 
* Bit 5 (0x20): Right Pants Leg enabled
 
* Bit 6 (0x40): Hat enabled
 
  
The most significant bit (bit 7, 0x80) appears to be unused.
+
Contains a list of key-value text entries that are included in any crash or disconnection report generated during connection to the server.
 
 
==== Command Suggestions Request ====
 
 
 
Sent when the client needs to tab-complete a <code>minecraft:ask_server</code> suggestion type.
 
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 7,242: Line 7,889:
 
  ! State
 
  ! State
 
  ! Bound To
 
  ! Bound To
  ! Field Name
+
  ! colspan="2"| Field Name
  ! Field Type
+
  ! colspan="2"| Field Type
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="2"| 0x0A
+
  | rowspan="3"| 0x7A
  | rowspan="2"| Play
+
  | rowspan="3"| Play
  | rowspan="2"| Server
+
  | rowspan="3"| Client
  | Transaction Id
+
  | colspan="2"| Details Count
  | VarInt
+
  | colspan="2"| {{Type|VarInt}} (32)
  | The id of the transaction that the server will send back to the client in the response of this packet. Client generates this and increments it each time it sends another tab completion that doesn't get a response.
+
  | The number of details in the following array.
 +
|-
 +
| rowspan="2"| Details
 +
| Title
 +
| rowspan="2"| {{Type|Array}}
 +
| {{Type|String}} (128)
 +
|
 
  |-
 
  |-
  | Text
+
  | Description
  | String (32500)
+
  | {{Type|String}} (4096)
  | All text behind the cursor without the <code>/</code> (e.g. to the left of the cursor in left-to-right languages like English).
+
  |
|}
+
|}
  
==== Acknowledge Configuration ====
+
==== Server Links ====
  
Sent by the client upon receiving a [[#Start Configuration|Start Configuration]] packet from the server.
+
This packet contains a list of links that the Notchian client will display in the menu available from the pause menu. Link labels can be built-in or custom (i.e., any text).
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 7,266: Line 7,919:
 
  ! State
 
  ! State
 
  ! Bound To
 
  ! Bound To
  ! Field Name
+
  ! colspan="2"| Field Name
  ! Field Type
+
  ! colspan="2"| Field Type
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="1"| 0x0B
+
  | rowspan="4"| 0x7B
  | rowspan="1"| Play
+
  | rowspan="4"| Play
  | rowspan="1"| Server
+
  | rowspan="4"| Client
  | colspan="3"| ''no fields''
+
| colspan="2"| Links Count
 +
  | colspan="2"| {{Type|VarInt}}
 +
| The number of links in the following array.
 +
|-
 +
| rowspan="3"| Links
 +
| Is built-in
 +
| rowspan="3"| {{Type|Array}}
 +
| {{Type|Boolean}}
 +
| Determines if the following label is built-in (from enum) or custom (text component).
 +
|-
 +
| Label
 +
| {{Type|VarInt}} {{Type|Enum}} / {{Type|Text Component}}
 +
| See below.
 +
|-
 +
| URL
 +
| {{Type|String}}
 +
| Valid URL.
 +
|}
 +
 
 +
{| class="wikitable"
 +
! ID
 +
! Name
 +
! Notes
 +
|-
 +
| 0
 +
| Bug Report
 +
| Displayed on connection error screen; included as a comment in the disconnection report.
 +
|-
 +
| 1
 +
| Community Guidelines
 +
|
 +
|-
 +
| 2
 +
| Support
 +
|
 +
|-
 +
| 3
 +
| Status
 +
|
 +
|-
 +
| 4
 +
| Feedback
 +
|
 +
|-
 +
| 5
 +
| Community
 +
|
 +
|-
 +
| 6
 +
| Website
 +
|
 +
|-
 +
| 7
 +
| Forums
 +
|
 +
|-
 +
| 8
 +
| News
 +
|
 +
|-
 +
| 9
 +
| Announcements
 +
|
 +
|-
 
  |}
 
  |}
  
This packet switches the connection state to [[#Configuration|configuration]].
+
=== Serverbound ===
  
==== Click Container Button ====
+
==== Confirm Teleportation ====
  
Used when clicking on window buttons.  Until 1.14, this was only used by enchantment tables.
+
Sent by client as confirmation of [[#Synchronize Player Position|Synchronize Player Position]].
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 7,290: Line 8,006:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="2"| 0x0C
+
  | ''protocol:''<br/><code>0x00</code><br/><br/>''resource:''<br/><code>accept_teleportation</code>
  | rowspan="2"| Play
+
  | Play
  | rowspan="2"| Server
+
  | Server
  | Window ID
+
  | Teleport ID
  | Byte
+
  | {{Type|VarInt}}
  | The ID of the window sent by [[#Open Screen|Open Screen]].
+
  | The ID given by the [[#Synchronize Player Position|Synchronize Player Position]] packet.
|-
 
| Button ID
 
| Byte
 
| Meaning depends on window type; see below.
 
 
  |}
 
  |}
 +
 +
==== Query Block Entity Tag ====
 +
 +
Used when <kbd>F3</kbd>+<kbd>I</kbd> is pressed while looking at a block.
  
 
{| class="wikitable"
 
{| class="wikitable"
  ! Window type
+
  ! Packet ID
  ! ID
+
! State
  ! Meaning
+
  ! Bound To
 +
! Field Name
 +
! Field Type
 +
  ! Notes
 
  |-
 
  |-
  | rowspan="3"| Enchantment Table
+
  | rowspan="2"| 0x01
  | 0 || Topmost enchantment.
+
  | rowspan="2"| Play
 +
| rowspan="2"| Server
 +
| Transaction ID
 +
| {{Type|VarInt}}
 +
| An incremental ID so that the client can verify that the response matches.
 
  |-
 
  |-
  | 1 || Middle enchantment.
+
  | Location
|-
+
  | {{Type|Position}}
| 2 || Bottom enchantment.
+
  | The location of the block to check.
|-
 
| rowspan="4"| Lectern
 
| 1 || Previous page (which does give a redstone output).
 
|-
 
| 2 || Next page.
 
|-
 
| 3 || Take Book.
 
|-
 
  | 100+page || Opened page number - 100 + number.
 
|-
 
  | Stonecutter
 
| colspan="2"| Recipe button number - 4*row + col.  Depends on the item.
 
|-
 
| Loom
 
| colspan="2"| Recipe button number - 4*row + col.  Depends on the item.
 
 
  |}
 
  |}
  
==== Click Container ====
+
==== Change Difficulty ====
  
This packet is sent by the client when the player clicks on a slot in a window.
+
Must have at least op level 2 to use.  Appears to only be used on singleplayer; the difficulty buttons are still disabled in multiplayer.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 7,338: Line 8,046:
 
  ! State
 
  ! State
 
  ! Bound To
 
  ! Bound To
  ! colspan="2"| Field Name
+
  ! Field Name
  ! colspan="2"| Field Type
+
  ! Field Type
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="9"| 0x0D
+
  | 0x02
  | rowspan="9"| Play
+
| Play
  | rowspan="9"| Server
+
  | Server
  | colspan="2"| Window ID
+
| New difficulty
  | colspan="2"| Unsigned Byte
+
  | {{Type|Byte}}
| colspan="2"| The ID of the window which was clicked. 0 for player inventory.
+
  | 0: peaceful, 1: easy, 2: normal, 3: hard .
 +
  |}
 +
 
 +
==== Acknowledge Message ====
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 
  |-
 
  |-
  | colspan="2"| State ID
+
  | rowspan="1"| 0x03
| colspan="2"| VarInt
+
  | rowspan="1"| Play
| colspan="2"| The last recieved State ID from either a [[#Set Container Slot|Set Container Slot]] or a [[#Set Container Content|Set Container Content]] packet
+
  | rowspan="1"| Server
|-
+
  | Message Count
| colspan="2"| Slot
+
  | {{Type|VarInt}}
| colspan="2"| Short
+
  |  
| colspan="2"| The clicked slot number, see below.
 
|-
 
| colspan="2"| Button
 
| colspan="2"| Byte
 
| colspan="2"| The button used in the click, see below.
 
|-
 
| colspan="2"| Mode
 
| colspan="2"| VarInt Enum
 
| colspan="2"| Inventory operation mode, see below.
 
|-
 
| colspan="2"| Length of the array
 
| colspan="2"| VarInt
 
| colspan="2"| Maximum value for Notchian server is 128 slots.
 
|-
 
  | rowspan="2"| Array of slots
 
| Slot number
 
  | rowspan="2"| Array (128)
 
| Short
 
  |
 
  |-
 
| Slot data
 
| Slot
 
| New data for this slot
 
|-
 
| colspan="2"| Carried item
 
| colspan="2"| [[Slot Data|Slot]]
 
  | colspan="2"| Item carried by the cursor. Has to be empty (item ID = -1) for drop mode, otherwise nothing will happen.
 
 
  |}
 
  |}
  
See [[Inventory]] for further information about how slots are indexed.
+
==== Chat Command ====
  
When right-clicking on a stack of items, half the stack will be picked up and half left in the slot. If the stack is an odd number, the half left in the slot will be smaller of the amounts.
+
{{Main|Chat}}
 
 
The distinct type of click performed by the client is determined by the combination of the Mode and Button fields.
 
  
 
{| class="wikitable"
 
{| class="wikitable"
  ! Mode
+
  ! Packet ID
  ! Button
+
  ! State
  ! Slot
+
  ! Bound To
  ! Trigger
+
  ! colspan="2"| Field Name
 +
! colspan="2"| Field Type
 +
! Notes
 
  |-
 
  |-
  ! rowspan="4"| 0
+
  | 0x04
  | 0
+
| Play
  | Normal
+
| Server
  | Left mouse click
+
| colspan="2"| Command
 +
  | colspan="2"| {{Type|String}} (32767)
 +
  | colspan="2"| The command typed by the client.
 +
  |}
 +
 
 +
==== Signed Chat Command ====
 +
 
 +
{{Main|Chat}}
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! colspan="2"| Field Name
 +
! colspan="2"| Field Type
 +
! Notes
 
  |-
 
  |-
  | 1
+
  | rowspan="8"| 0x05
  | Normal
+
| rowspan="8"| Play
  | Right mouse click
+
| rowspan="8"| Server
 +
| colspan="2"| Command
 +
  | colspan="2"| {{Type|String}} (32767)
 +
  | colspan="2"| The command typed by the client.
 
  |-
 
  |-
  | 0
+
  | colspan="2"| Timestamp
  | -999
+
  | colspan="2"| {{Type|Long}}
  | Left click outside inventory (drop cursor stack)
+
  | colspan="2"| The timestamp that the command was executed.
 
  |-
 
  |-
  | 1
+
  | colspan="2"| Salt
  | -999
+
  | colspan="2"| {{Type|Long}}
  | Right click outside inventory (drop cursor single item)
+
  | colspan="2"| The salt for the following argument signatures.
 
  |-
 
  |-
  ! rowspan="2"| 1
+
  | colspan="2"| Array length
  | 0
+
  | colspan="2"| {{Type|VarInt}}
  | Normal
+
  | colspan="2"| Number of entries in the following array. The maximum length in Notchian server is 8.
| Shift + left mouse click
 
 
  |-
 
  |-
  | 1
+
  | rowspan="2"| Array of argument signatures
  | Normal
+
| Argument name
  | Shift + right mouse click ''(identical behavior)''
+
  | rowspan="2"| {{Type|Array}} (8)
 +
  | {{Type|String}} (16)
 +
| The name of the argument that is signed by the following signature.
 
  |-
 
  |-
  ! rowspan="7"| 2
+
  | Signature
  | 0
+
  | {{Type|Byte Array}} (256)
| Normal
+
  | The signature that verifies the argument. Always 256 bytes and is not length-prefixed.
  | Number key 1
 
 
  |-
 
  |-
  | 1
+
  | colspan="2"| Message Count
  | Normal
+
| colspan="2"| {{Type|VarInt}}
  | Number key 2
+
  | colspan="2"|
 +
  |-
 +
| colspan="2"| Acknowledged
 +
| colspan="2"| {{Type|Fixed BitSet}} (20)
 +
| colspan="2"|
 +
|}
 +
 
 +
==== Chat Message ====
 +
 
 +
{{Main|Chat}}
 +
 
 +
Used to send a chat message to the server.  The message may not be longer than 256 characters or else the server will kick the client.
 +
 
 +
The server will broadcast a [[#Player Chat Message|Player Chat Message]] packet with Chat Type <code>minecraft:chat</code> to all players that haven't disabled chat (including the player that sent the message). See [[Chat#Processing chat]] for more information.
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 
  |-
 
  |-
  | 2
+
  | rowspan="7"| ''protocol:''<br/><code>0x06</code><br/><br/>''resource:''<br/><code>chat</code>
  | Normal
+
  | rowspan="7"| Play
  | Number key 3
+
| rowspan="7"| Server
 +
| Message
 +
| {{Type|String}} (256)
 +
  |
 
  |-
 
  |-
  |
+
  | Timestamp
  |
+
  | {{Type|Long}}
  |
+
  |
 
  |-
 
  |-
  | 8
+
  | Salt
  | Normal
+
  | {{Type|Long}}
  | Number key 9
+
  | The salt used to verify the signature hash.
 
  |-
 
  |-
  |
+
  | Has Signature
  |
+
  | {{Type|Boolean}}
  | Button is used as the slot index (impossible in vanilla clients)
+
  | Whether the next field is present.
 
  |-
 
  |-
  | 40
+
  | Signature
  | Normal
+
  | {{Type|Optional}} {{Type|Byte Array}} (256)
  | Offhand swap key F
+
  | The signature used to verify the chat message's authentication. When present, always 256 bytes and not length-prefixed.
 
  |-
 
  |-
  ! 3
+
  | Message Count
  | 2
+
  | {{Type|VarInt}}
| Normal
+
  |
  | Middle click, only defined for creative players in non-player inventories.
 
 
  |-
 
  |-
  ! rowspan="2"| 4
+
| Acknowledged
  | 0
+
| {{Type|Fixed BitSet}} (20)
  | Normal*
+
|
| Drop key (Q) (* Clicked item is always empty)
+
|}
 +
 
 +
==== Player Session ====
 +
 
 +
{| class="wikitable"
 +
  ! Packet ID
 +
! State
 +
! Bound To
 +
! colspan="2"| Field Name
 +
  ! Field Type
 +
  ! Notes
 
  |-
 
  |-
  | 1
+
  | rowspan="6"| 0x07
  | Normal*
+
| rowspan="6"| Play
  | Control + Drop key (Q) (* Clicked item is always empty)
+
| rowspan="6"| Server
 +
  | colspan="2"| Session Id
 +
| {{Type|UUID}}
 +
  |
 
  |-
 
  |-
  ! rowspan="9"| 5
+
  | rowspan="5"| Public Key
  | 0
+
  | Expires At
  | -999
+
  | {{Type|Long}}
  | Starting left mouse drag
+
  | The time the play session key expires in [https://en.wikipedia.org/wiki/Unix_time epoch] milliseconds.
 
  |-
 
  |-
  | 4
+
  | Public Key Length
  | -999
+
  | {{Type|VarInt}}
  | Starting right mouse drag
+
  | Length of the proceeding public key. Maximum length in Notchian server is 512 bytes.
 
  |-
 
  |-
  | 8
+
  | Public Key
  | -999
+
  | {{Type|Byte Array}} (512)
  | Starting middle mouse drag, only defined for creative players in non-player inventories.
+
  | A byte array of an X.509-encoded public key.
 
  |-
 
  |-
  | 1
+
  | Key Signature Length
  | Normal
+
  | {{Type|VarInt}}
  | Add slot for left-mouse drag
+
  | Length of the proceeding key signature array. Maximum length in Notchian server is 4096 bytes.
 
  |-
 
  |-
  | 5
+
  | Key Signature
  | Normal
+
  | {{Type|Byte Array}} (4096)
| Add slot for right-mouse drag
+
  | The signature consists of the player UUID, the key expiration timestamp, and the public key data. These values are hashed using [https://en.wikipedia.org/wiki/SHA-1 SHA-1] and signed using Mojang's private [https://en.wikipedia.org/wiki/RSA_(cryptosystem) RSA] key.
  |-
+
  |}
| 9
+
 
| Normal
+
==== Chunk Batch Received ====
| Add slot for middle-mouse drag, only defined for creative players in non-player inventories.
+
 
|-
+
Notifies the server that the chunk batch has been received by the client. The server uses the value sent in this packet to adjust the number of chunks to be sent in a batch.
| 2
 
| -999
 
  | Ending left mouse drag
 
|-
 
| 6
 
| -999
 
| Ending right mouse drag
 
|-
 
| 10
 
| -999
 
| Ending middle mouse drag, only defined for creative players in non-player inventories.
 
|-
 
! rowspan="2"| 6
 
| 0
 
| Normal
 
| Double click
 
|-
 
| 1
 
| Normal
 
| Pickup all but check items in reverse order (impossible in vanilla clients)
 
|}
 
  
Starting from version 1.5, “painting mode” is available for use in inventory windows. It is done by picking up stack of something (more than 1 item), then holding mouse button (left, right or middle) and dragging held stack over empty (or same type in case of right button) slots. In that case client sends the following to server after mouse button release (omitting first pickup packet which is sent as usual):
+
The Notchian server will stop sending further chunk data until the client acknowledges the sent chunk batch. After the first acknowledgement, the server adjusts this number to allow up to 10 unacknowledged batches.
 
 
# packet with mode 5, slot -999, button (0 for left | 4 for right);
 
# packet for every slot painted on, mode is still 5, button (1 | 5);
 
# packet with mode 5, slot -999, button (2 | 6);
 
 
 
If any of the painting packets other than the “progress” ones are sent out of order (for example, a start, some slots, then another start; or a left-click in the middle) the painting status will be reset.
 
 
 
==== Close Container ====
 
 
 
This packet is sent by the client when closing a window.
 
 
 
Notchian clients send a Close Window packet with Window ID 0 to close their inventory even though there is never an [[#Open Screen|Open Screen]] packet for the inventory.
 
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 7,534: Line 8,247:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | 0x0E
+
  | rowspan="1"| ''protocol:''<br/><code>0x08</code><br/><br/>''resource:''<br/><code>chunk_batch_received</code>
  | Play
+
  | rowspan="1"| Play
  | Server
+
  | rowspan="1"| Server
  | Window ID
+
  | Chunks per tick
  | Unsigned Byte
+
  | {{Type|Float}}
  | This is the ID of the window that was closed. 0 for player inventory.
+
  | Desired chunks per tick.
 
  |}
 
  |}
  
==== Serverbound Plugin Message (play) ====
+
==== Client Status ====
 
 
{{Main|Plugin channels}}
 
 
 
Mods and plugins can use this to send their data. Minecraft itself uses some [[plugin channel]]s. These internal channels are in the <code>minecraft</code> namespace.
 
 
 
More documentation on this: [https://dinnerbone.com/blog/2012/01/13/minecraft-plugin-channels-messaging/ https://dinnerbone.com/blog/2012/01/13/minecraft-plugin-channels-messaging/]
 
 
 
Note that the length of Data is known only from the packet length, since the packet has no length field of any kind.
 
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 7,560: Line 8,265:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="2"| 0x0F
+
  | ''protocol:''<br/><code>0x09</code><br/><br/>''resource:''<br/><code>client_command</code>
  | rowspan="2"| Play
+
  | Play
  | rowspan="2"| Server
+
  | Server
  | Channel
+
  | Action ID
  | Identifier
+
  | {{Type|VarInt}} {{Type|Enum}}
| Name of the [[plugin channel]] used to send the data.
+
  | See below
|-
 
| Data
 
  | Byte Array (32767)
 
| Any data, depending on the channel. <code>minecraft:</code> channels are documented [[plugin channel|here]]. The length of this array must be inferred from the packet length.
 
 
  |}
 
  |}
  
In Notchian server, the maximum data length is 32767 bytes.
+
''Action ID'' values:
 
 
==== Edit Book ====
 
  
 
{| class="wikitable"
 
{| class="wikitable"
  ! Packet ID
+
  |-
  ! State
+
  ! Action ID
! Bound To
+
  ! Action
! Field Name
 
  ! Field Type
 
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="5"| 0x10
+
  | 0
  | rowspan="5"| Play
+
  | Perform respawn
  | rowspan="5"| Server
+
  | Sent when the client is ready to complete login and when the client is ready to respawn after death.
| Slot
 
| VarInt
 
| The hotbar slot where the written book is located
 
 
  |-
 
  |-
  | Count
+
  | 1
  | VarInt
+
  | Request stats
  | Number of elements in the following array. Maximum array size is 200.
+
  | Sent when the client opens the Statistics menu.
|-
 
| Entries
 
| Array (200) of Strings (8192)
 
| Text from each page. Maximum string length is 8192 chars.
 
|-
 
| Has title
 
| Boolean
 
| If true, the next field is present. true if book is being signed, false if book is being edited.
 
|-
 
| Title
 
| Optional String (128)
 
| Title of book.
 
 
  |}
 
  |}
  
==== Query Entity Tag ====
+
==== Client Information (play) ====
  
Used when <kbd>F3</kbd>+<kbd>I</kbd> is pressed while looking at an entity.
+
Sent when the player connects, or when settings are changed.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 7,620: Line 8,302:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="2"| 0x11
+
  | rowspan="8"| 0x0A
  | rowspan="2"| Play
+
  | rowspan="8"| Play
  | rowspan="2"| Server
+
  | rowspan="8"| Server
  | Transaction ID
+
  | Locale
  | VarInt
+
  | {{Type|String}} (16)
  | An incremental ID so that the client can verify that the response matches.
+
  | e.g. <code>en_GB</code>.
 
  |-
 
  |-
  | Entity ID
+
  | View Distance
  | VarInt
+
  | {{Type|Byte}}
  | The ID of the entity to query.
+
| Client-side render distance, in chunks.
 +
|-
 +
| Chat Mode
 +
| {{Type|VarInt}} {{Type|Enum}}
 +
| 0: enabled, 1: commands only, 2: hidden.  See [[Chat#Client chat mode]] for more information.
 +
|-
 +
| Chat Colors
 +
| {{Type|Boolean}}
 +
| “Colors” multiplayer setting. Can the chat be colored?
 +
|-
 +
| Displayed Skin Parts
 +
| {{Type|Unsigned Byte}}
 +
| Bit mask, see below.
 +
|-
 +
| Main Hand
 +
| {{Type|VarInt}} {{Type|Enum}}
 +
| 0: Left, 1: Right.
 +
|-
 +
| Enable text filtering
 +
  | {{Type|Boolean}}
 +
| Enables filtering of text on signs and written book titles. Currently always false (i.e. the filtering is disabled)
 +
|-
 +
| Allow server listings
 +
| {{Type|Boolean}}
 +
| Servers usually list online players, this option should let you not show up in that list.
 
  |}
 
  |}
  
==== Interact ====
+
''Displayed Skin Parts'' flags:
  
This packet is sent from the client to the server when the client attacks or right-clicks another entity (a player, minecart, etc).
+
* Bit 0 (0x01): Cape enabled
 +
* Bit 1 (0x02): Jacket enabled
 +
* Bit 2 (0x04): Left Sleeve enabled
 +
* Bit 3 (0x08): Right Sleeve enabled
 +
* Bit 4 (0x10): Left Pants Leg enabled
 +
* Bit 5 (0x20): Right Pants Leg enabled
 +
* Bit 6 (0x40): Hat enabled
  
A Notchian server only accepts this packet if the entity being attacked/used is visible without obstruction and within a 4-unit radius of the player's position.
+
The most significant bit (bit 7, 0x80) appears to be unused.
  
The target X, Y, and Z fields represent the difference between the vector location of the cursor at the time of the packet and the entity's position.
+
==== Command Suggestions Request ====
  
Note that middle-click in creative mode is interpreted by the client and sent as a [[#Set Creative Mode Slot|Set Creative Mode Slot]] packet instead.
+
Sent when the client needs to tab-complete a <code>minecraft:ask_server</code> suggestion type.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 7,650: Line 8,362:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="7"| 0x12
+
  | rowspan="2"| 0x0B
  | rowspan="7"| Play
+
  | rowspan="2"| Play
  | rowspan="7"| Server
+
  | rowspan="2"| Server
  | Entity ID
+
  | Transaction Id
  | VarInt
+
  | {{Type|VarInt}}
  | The ID of the entity to interact.
+
  | The id of the transaction that the server will send back to the client in the response of this packet. Client generates this and increments it each time it sends another tab completion that doesn't get a response.
 
  |-
 
  |-
  | Type
+
  | Text
  | VarInt Enum
+
  | {{Type|String}} (32500)
| 0: interact, 1: attack, 2: interact at.
+
  | All text behind the cursor without the <code>/</code> (e.g. to the left of the cursor in left-to-right languages like English).
|-
+
  |}
| Target X
+
 
| Optional Float
+
==== Acknowledge Configuration ====
| Only if Type is interact at.
+
 
|-
+
Sent by the client upon receiving a [[#Start Configuration|Start Configuration]] packet from the server.
  | Target Y
 
| Optional Float
 
| Only if Type is interact at.
 
|-
 
| Target Z
 
| Optional Float
 
| Only if Type is interact at.
 
|-
 
| Hand
 
| Optional VarInt Enum
 
| Only if Type is interact or interact at; 0: main hand, 1: off hand.
 
|-
 
| Sneaking
 
| Boolean
 
| If the client is sneaking.
 
  |}
 
 
 
==== Jigsaw Generate ====
 
 
 
Sent when Generate is pressed on the {{Minecraft Wiki|Jigsaw Block}} interface.
 
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 7,694: Line 8,386:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="3"| 0x13
+
  | rowspan="1"| 0x0C
  | rowspan="3"| Play
+
  | rowspan="1"| Play
  | rowspan="3"| Server
+
  | rowspan="1"| Server
  | Location
+
  | colspan="3"| ''no fields''
| Position
 
| Block entity location.
 
|-
 
| Levels
 
| VarInt
 
| Value of the levels slider/max depth to generate.
 
|-
 
| Keep Jigsaws
 
| Boolean
 
|
 
 
  |}
 
  |}
  
==== Serverbound Keep Alive (play) ====
+
This packet switches the connection state to [[#Configuration|configuration]].
 +
 
 +
==== Click Container Button ====
  
The server will frequently send out a keep-alive (see [[#Clientbound Keep Alive (play)|Clientbound Keep Alive]]), each containing a random ID. The client must respond with the same packet.
+
Used when clicking on window buttons.  Until 1.14, this was only used by enchantment tables.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 7,722: Line 8,406:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | 0x14
+
  | rowspan="2"| 0x0D
  | Play
+
  | rowspan="2"| Play
  | Server
+
  | rowspan="2"| Server
  | Keep Alive ID
+
  | Window ID
  | Long
+
| {{Type|Byte}}
  |
+
| The ID of the window sent by [[#Open Screen|Open Screen]].
 +
|-
 +
| Button ID
 +
  | {{Type|Byte}}
 +
  | Meaning depends on window type; see below.
 
  |}
 
  |}
 
==== Lock Difficulty ====
 
 
Must have at least op level 2 to use.  Appears to only be used on singleplayer; the difficulty buttons are still disabled in multiplayer.
 
  
 
{| class="wikitable"
 
{| class="wikitable"
  ! Packet ID
+
  ! Window type
  ! State
+
! ID
  ! Bound To
+
  ! Meaning
  ! Field Name
+
|-
  ! Field Type
+
| rowspan="3"| Enchantment Table
  ! Notes
+
| 0 || Topmost enchantment.
 +
|-
 +
| 1 || Middle enchantment.
 +
|-
 +
| 2 || Bottom enchantment.
 +
|-
 +
| rowspan="4"| Lectern
 +
| 1 || Previous page (which does give a redstone output).
 +
|-
 +
  | 2 || Next page.
 +
|-
 +
| 3 || Take Book.
 +
|-
 +
| 100+page || Opened page number - 100 + number.
 +
  |-
 +
  | Stonecutter
 +
  | colspan="2"| Recipe button number - 4*row + col.  Depends on the item.
 
  |-
 
  |-
  | 0x15
+
  | Loom
  | Play
+
  | colspan="2"| Recipe button number - 4*row + col. Depends on the item.
| Server
 
| Locked
 
  | Boolean
 
|
 
 
  |}
 
  |}
  
==== Set Player Position ====
+
==== Click Container ====
  
Updates the player's XYZ position on the server.
+
This packet is sent by the client when the player clicks on a slot in a window.
 
 
Checking for moving too fast is achieved like this:
 
 
 
* Each server tick, the player's current position is stored
 
* When a player moves, the changes in x, y, and z coordinates are compared with the positions from the previous tick (&Delta;x, &Delta;y, &Delta;z)
 
* Total movement distance squared is computed as &Delta;x&sup2; + &Delta;y&sup2; + &Delta;z&sup2;
 
* The expected movement distance squared is computed as velocityX&sup2; + velocityY&sup2; + velocityZ&sup2;
 
* If the total movement distance squared value minus the expected movement distance squared value is more than 100 (300 if the player is using an elytra), they are moving too fast.
 
 
 
If the player is moving too fast, it will be logged that "<player> moved too quickly! " followed by the change in x, y, and z, and the player will be teleported back to their current (before this packet) serverside position.
 
 
 
Also, if the absolute value of X or the absolute value of Z is a value greater than 3.2×10<sup>7</sup>, or X, Y, or Z are not finite (either positive infinity, negative infinity, or NaN), the client will be kicked for “Invalid move player packet received”.
 
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 7,770: Line 8,454:
 
  ! State
 
  ! State
 
  ! Bound To
 
  ! Bound To
  ! Field Name
+
  ! colspan="2"| Field Name
  ! Field Type
+
  ! colspan="2"| Field Type
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="4"| 0x16
+
  | rowspan="9"| 0x0E
  | rowspan="4"| Play
+
  | rowspan="9"| Play
  | rowspan="4"| Server
+
  | rowspan="9"| Server
  | X
+
  | colspan="2"| Window ID
  | Double
+
  | colspan="2"| {{Type|Unsigned Byte}}
  | Absolute position.
+
  | colspan="2"| The ID of the window which was clicked. 0 for player inventory. The server ignores any packets targeting a Window ID other than the current one, including ignoring 0 when any other window is open.
 
  |-
 
  |-
  | Feet Y
+
  | colspan="2"| State ID
  | Double
+
  | colspan="2"| {{Type|VarInt}}
  | Absolute feet position, normally Head Y - 1.62.
+
  | colspan="2"| The last received State ID from either a [[#Set Container Slot|Set Container Slot]] or a [[#Set Container Content|Set Container Content]] packet.
 
  |-
 
  |-
  | Z
+
  | colspan="2"| Slot
  | Double
+
  | colspan="2"| {{Type|Short}}
  | Absolute position.
+
  | colspan="2"| The clicked slot number, see below.
 
  |-
 
  |-
  | On Ground
+
  | colspan="2"| Button
| Boolean
+
  | colspan="2"| {{Type|Byte}}
  | True if the client is on the ground, false otherwise.
+
| colspan="2"| The button used in the click, see below.
|}
 
 
 
==== Set Player Position and Rotation ====
 
 
 
A combination of [[#Set Player Rotation|Move Player Rotation]] and [[#Set Player Position|Move Player Position]].
 
 
 
{| class="wikitable"
 
! Packet ID
 
! State
 
! Bound To
 
! Field Name
 
! Field Type
 
! Notes
 
 
  |-
 
  |-
  | rowspan="6"| 0x17
+
  | colspan="2"| Mode
  | rowspan="6"| Play
+
  | colspan="2"| {{Type|VarInt}} {{Type|Enum}}
  | rowspan="6"| Server
+
  | colspan="2"| Inventory operation mode, see below.
| X
 
| Double
 
| Absolute position.
 
 
  |-
 
  |-
  | Feet Y
+
  | colspan="2"| Length of the array
  | Double
+
  | colspan="2"| {{Type|VarInt}}
  | Absolute feet position, normally Head Y - 1.62.
+
  | colspan="2"| Maximum value for Notchian server is 128 slots.
 
  |-
 
  |-
  | Z
+
  | rowspan="2"| Array of changed slots
  | Double
+
| Slot number
  | Absolute position.
+
| rowspan="2"| {{Type|Array}} (128)
 +
  | {{Type|Short}}
 +
  |
 
  |-
 
  |-
  | Yaw
+
  | Slot data
  | Float
+
  | {{Type|Slot}}
  | Absolute rotation on the X Axis, in degrees.
+
  | New data for this slot, in the client's opinion; see below.
 
  |-
 
  |-
  | Pitch
+
  | colspan="2"| Carried item
| Float
+
  | colspan="2"| [[Slot Data|Slot]]
  | Absolute rotation on the Y Axis, in degrees.
+
  | colspan="2"| Item carried by the cursor. Has to be empty (item ID = -1) for drop mode, otherwise nothing will happen.
|-
 
| On Ground
 
  | Boolean
 
| True if the client is on the ground, false otherwise.
 
 
  |}
 
  |}
  
==== Set Player Rotation ====
+
See [[Inventory]] for further information about how slots are indexed.
[[File:Minecraft-trig-yaw.png|thumb|The unit circle for yaw]]
 
[[File:Yaw.png|thumb|The unit circle of yaw, redrawn]]
 
  
Updates the direction the player is looking in.
+
After performing the action, the server compares the results to the slot change information included in the packet, as applied on top of the server's view of the container's state prior to the action. For any slots that do not match, it sends [[#Set Container Slot|Set Container Slot]] packets containing the correct results. If State ID does not match the last ID sent by the server, it will instead send a full [[#Set Container Content|Set Container Content]] to resynchronize the client.
  
Yaw is measured in degrees, and does not follow classical trigonometry rules. The unit circle of yaw on the XZ-plane starts at (0, 1) and turns counterclockwise, with 90 at (-1, 0), 180 at (0,-1) and 270 at (1, 0). Additionally, yaw is not clamped to between 0 and 360 degrees; any number is valid, including negative numbers and numbers greater than 360.
+
When right-clicking on a stack of items, half the stack will be picked up and half left in the slot. If the stack is an odd number, the half left in the slot will be smaller of the amounts.
  
Pitch is measured in degrees, where 0 is looking straight ahead, -90 is looking straight up, and 90 is looking straight down.
+
The distinct type of click performed by the client is determined by the combination of the Mode and Button fields.
  
The yaw and pitch of player (in degrees), standing at point (x0, y0, z0) and looking towards point (x, y, z) can be calculated with:
+
{| class="wikitable"
 
+
  ! Mode
dx = x-x0
+
  ! Button
dy = y-y0
+
  ! Slot
dz = z-z0
+
  ! Trigger
r = sqrt( dx*dx + dy*dy + dz*dz )
 
yaw = -atan2(dx,dz)/PI*180
 
if yaw < 0 then
 
    yaw = 360 + yaw
 
pitch = -arcsin(dy/r)/PI*180
 
 
 
You can get a unit vector from a given yaw/pitch via:
 
 
 
x = -cos(pitch) * sin(yaw)
 
y = -sin(pitch)
 
z =  cos(pitch) * cos(yaw)
 
 
 
{| class="wikitable"
 
  ! Packet ID
 
! State
 
! Bound To
 
  ! Field Name
 
  ! Field Type
 
  ! Notes
 
 
  |-
 
  |-
  | rowspan="3"| 0x18
+
  ! rowspan="4"| 0
| rowspan="3"| Play
+
  | 0
| rowspan="3"| Server
+
  | Normal
  | Yaw
+
  | Left mouse click
  | Float
 
  | Absolute rotation on the X Axis, in degrees.
 
 
  |-
 
  |-
  | Pitch
+
  | 1
  | Float
+
  | Normal
  | Absolute rotation on the Y Axis, in degrees.
+
  | Right mouse click
 
  |-
 
  |-
  | On Ground
+
  | 0
  | Boolean
+
  | -999
  | True if the client is on the ground, false otherwise.
+
  | Left click outside inventory (drop cursor stack)
|}
 
 
 
==== Set Player On Ground ====
 
 
 
This packet as well as [[#Set Player Position|Set Player Position]], [[#Set Player Rotation|Set Player Rotation]], and [[#Set Player Position and Rotation|Set Player Position and Rotation]] are called the “serverbound movement packets”. Vanilla clients will send Move Player Position once every 20 ticks even for a stationary player.
 
 
 
This packet is used to indicate whether the player is on ground (walking/swimming), or airborne (jumping/falling).
 
 
 
When dropping from sufficient height, fall damage is applied when this state goes from false to true. The amount of damage applied is based on the point where it last changed from true to false. Note that there are several movement related packets containing this state.
 
 
 
{| class="wikitable"
 
! Packet ID
 
! State
 
! Bound To
 
! Field Name
 
! Field Type
 
! Notes
 
 
  |-
 
  |-
  | 0x19
+
  | 1
  | Play
+
  | -999
  | Server
+
  | Right click outside inventory (drop cursor single item)
  | On Ground
+
  |-
  | Boolean
+
  ! rowspan="2"| 1
  | True if the client is on the ground, false otherwise.
+
  | 0
  |}
+
  | Normal
 
+
| Shift + left mouse click
==== Move Vehicle ====
 
 
 
Sent when a player moves in a vehicle. Fields are the same as in [[#Set Player Position and Rotation|Set Player Position and Rotation]]. Note that all fields use absolute positioning and do not allow for relative positioning.
 
 
 
{| class="wikitable"
 
! Packet ID
 
! State
 
! Bound To
 
! Field Name
 
! Field Type
 
! Notes
 
 
  |-
 
  |-
  | rowspan="5"| 0x1A
+
  | 1
| rowspan="5"| Play
+
  | Normal
| rowspan="5"| Server
+
  | Shift + right mouse click ''(identical behavior)''
| X
 
  | Double
 
  | Absolute position (X coordinate).
 
 
  |-
 
  |-
  | Y
+
  ! rowspan="7"| 2
  | Double
+
  | 0
  | Absolute position (Y coordinate).
+
  | Normal
 +
| Number key 1
 
  |-
 
  |-
  | Z
+
  | 1
  | Double
+
  | Normal
  | Absolute position (Z coordinate).
+
  | Number key 2
 
  |-
 
  |-
  | Yaw
+
  | 2
  | Float
+
  | Normal
  | Absolute rotation on the vertical axis, in degrees.
+
  | Number key 3
 
  |-
 
  |-
  | Pitch
+
  |
  | Float
+
  |
  | Absolute rotation on the horizontal axis, in degrees.
+
  |
|}
 
 
 
==== Paddle Boat ====
 
 
 
Used to ''visually'' update whether boat paddles are turning.  The server will update the [[Entity_metadata#Boat|Boat entity metadata]] to match the values here.
 
 
 
{| class="wikitable"
 
! Packet ID
 
! State
 
! Bound To
 
! Field Name
 
! Field Type
 
! Notes
 
 
  |-
 
  |-
  | rowspan="2"| 0x1B
+
  | 8
| rowspan="2"| Play
+
  | Normal
| rowspan="2"| Server
+
  | Number key 9
| Left paddle turning
 
  | Boolean
 
  |
 
 
  |-
 
  |-
  | Right paddle turning
+
  |
  | Boolean
+
  |
  |
+
  | Button is used as the slot index (impossible in vanilla clients)
|}
 
 
 
Right paddle turning is set to true when the left button or forward button is held, left paddle turning is set to true when the right button or forward button is held.
 
 
 
==== Pick Item ====
 
 
 
Used to swap out an empty space on the hotbar with the item in the given inventory slot.  The Notchian client uses this for pick block functionality (middle click) to retrieve items from the inventory.
 
 
 
{| class="wikitable"
 
! Packet ID
 
! State
 
! Bound To
 
! Field Name
 
! Field Type
 
! Notes
 
 
  |-
 
  |-
  | 0x1C
+
  | 40
  | Play
+
  | Normal
  | Server
+
  | Offhand swap key F
| Slot to use
 
| VarInt
 
| See [[Inventory]].
 
|}
 
 
 
The server will first search the player's hotbar for an empty slot, starting from the current slot and looping around to the slot before it.  If there are no empty slots, it will start a second search from the current slot and find the first slot that does not contain an enchanted item.  If there still are no slots that meet that criteria, then the server will use the currently selected slot.
 
 
 
After finding the appropriate slot, the server swaps the items and then send 3 packets:
 
 
 
* [[#Set Container Slot|Set Container Slot]], with window ID set to -2 and slot set to the newly chosen slot and the item set to the item that is now in that slot (which was previously at the slot the client requested)
 
* Set Slot, with window ID set to -2 and slot set to the slot the player requested, with the item that is now in that slot and was previously on the hotbar slot
 
* [[#Set Held Item|Set Held Item]], with the slot set to the newly chosen slot.
 
 
 
==== Ping Request (play) ====
 
 
 
{| class="wikitable"
 
! Packet ID
 
! State
 
! Bound To
 
! Field Name
 
! Field Type
 
! Notes
 
 
  |-
 
  |-
  | 0x1D
+
  ! 3
  | Play
+
  | 2
  | Server
+
  | Normal
  | Payload
+
  | Middle click, only defined for creative players in non-player inventories.
| Long
 
| May be any number. Notchian clients use a system-dependent time value which is counted in milliseconds.
 
|}
 
 
 
==== Place Recipe ====
 
 
 
This packet is sent when a player clicks a recipe in the crafting book that is craftable (white border).
 
 
 
{| class="wikitable"
 
! Packet ID
 
! State
 
! Bound To
 
! Field Name
 
! Field Type
 
! Notes
 
 
  |-
 
  |-
  | rowspan="3"| 0x1E
+
  ! rowspan="2"| 4
| rowspan="3"| Play
+
  | 0
| rowspan="3"| Server
+
  | Normal*
  | Window ID
+
  | Drop key (Q) (* Clicked item is always empty)
  | Byte
 
  |
 
 
  |-
 
  |-
  | Recipe
+
  | 1
  | Identifier
+
  | Normal*
  | A recipe ID.
+
  | Control + Drop key (Q) (* Clicked item is always empty)
 
  |-
 
  |-
  | Make all
+
  ! rowspan="9"| 5
  | Boolean
+
  | 0
  | Affects the amount of items processed; true if shift is down when clicked.
+
  | -999
  |}
+
  | Starting left mouse drag
 
 
==== Player Abilities ====
 
 
 
The vanilla client sends this packet when the player starts/stops flying with the Flags parameter changed accordingly.
 
 
 
{| class="wikitable"
 
! Packet ID
 
! State
 
! Bound To
 
! Field Name
 
! Field Type
 
! Notes
 
 
  |-
 
  |-
  | 0x1F
+
  | 4
  | Play
+
  | -999
  | Server
+
  | Starting right mouse drag
  | Flags
+
  |-
  | Byte
+
  | 8
  | Bit mask. 0x02: is flying.
+
  | -999
 +
| Starting middle mouse drag, only defined for creative players in non-player inventories.
 +
|-
 +
| 1
 +
| Normal
 +
| Add slot for left-mouse drag
 +
|-
 +
| 5
 +
| Normal
 +
| Add slot for right-mouse drag
 +
|-
 +
| 9
 +
| Normal
 +
| Add slot for middle-mouse drag, only defined for creative players in non-player inventories.
 +
|-
 +
| 2
 +
| -999
 +
| Ending left mouse drag
 +
|-
 +
| 6
 +
| -999
 +
| Ending right mouse drag
 +
|-
 +
| 10
 +
| -999
 +
| Ending middle mouse drag, only defined for creative players in non-player inventories.
 +
|-
 +
! rowspan="2"| 6
 +
| 0
 +
| Normal
 +
| Double click
 +
|-
 +
| 1
 +
| Normal
 +
| Pickup all but check items in reverse order (impossible in vanilla clients)
 
  |}
 
  |}
  
==== Player Action ====
+
Starting from version 1.5, “painting mode” is available for use in inventory windows. It is done by picking up stack of something (more than 1 item), then holding mouse button (left, right or middle) and dragging held stack over empty (or same type in case of right button) slots. In that case client sends the following to server after mouse button release (omitting first pickup packet which is sent as usual):
 +
 
 +
# packet with mode 5, slot -999, button (0 for left | 4 for right);
 +
# packet for every slot painted on, mode is still 5, button (1 | 5);
 +
# packet with mode 5, slot -999, button (2 | 6);
 +
 
 +
If any of the painting packets other than the “progress” ones are sent out of order (for example, a start, some slots, then another start; or a left-click in the middle) the painting status will be reset.
 +
 
 +
==== Close Container ====
 +
 
 +
This packet is sent by the client when closing a window.
  
Sent when the player mines a block. A Notchian server only accepts digging packets with coordinates within a 6-unit radius between the center of the block and 1.5 units from the player's feet (''not'' their eyes).
+
Notchian clients send a Close Window packet with Window ID 0 to close their inventory even though there is never an [[#Open Screen|Open Screen]] packet for the inventory.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 8,077: Line 8,652:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="4"| 0x20
+
  | 0x0F
  | rowspan="4"| Play
+
  | Play
  | rowspan="4"| Server
+
  | Server
  | Status
+
  | Window ID
  | VarInt Enum
+
  | {{Type|Unsigned Byte}}
  | The action the player is taking against the block (see below).
+
  | This is the ID of the window that was closed. 0 for player inventory.
 +
|}
 +
 
 +
==== Change Container Slot State ====
 +
 
 +
This packet is sent by the client when toggling the state of a Crafter.
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 
  |-
 
  |-
  | Location
+
  | rowspan="3"| 0x10
  | Position
+
  | rowspan="3"| Play
  | Block position.
+
| rowspan="3"| Server
 +
| Slot ID
 +
| {{Type|VarInt}}
 +
  | This is the ID of the slot that was changed.
 
  |-
 
  |-
  | Face
+
  | Window ID
  | Byte Enum
+
  | {{Type|VarInt}}
  | The face being hit (see below).
+
  | This is the ID of the window that was changed.
 
  |-
 
  |-
  | Sequence
+
  | State
  | VarInt
+
  | {{Type|Boolean}}
 +
| The new state of the slot. True for enabled, false for disabled.
 
  |}
 
  |}
  
Status can be one of seven values:
+
==== Cookie Response (play) ====
 +
 
 +
Response to a [[#Cookie_Request_(play)|Cookie Request (play)]] from the server. The Notchian server only accepts responses of up to 5 kiB in size.
  
 
{| class="wikitable"
 
{| class="wikitable"
  ! Value
+
  ! Packet ID
  ! Meaning
+
  ! State
 +
! Bound To
 +
! colspan="2"| Field Name
 +
! colspan="2"| Field Type
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | 0
+
  | rowspan="4"| 0x11
| Started digging
+
  | rowspan="4"| Play
  |
+
  | rowspan="4"| Server
|-
+
  | colspan="2"| Key
  | 1
+
  | colspan="2"| {{Type|Identifier}}
| Cancelled digging
+
  | The identifier of the cookie.
  | Sent when the player lets go of the Mine Block key (default: left click).
 
|-
 
  | 2
 
| Finished digging
 
  | Sent when the client thinks it is finished.
 
 
  |-
 
  |-
  | 3
+
  | colspan="2"| Has Payload
| Drop item stack
+
  | colspan="2"| {{Type|Boolean}}
| Triggered by using the Drop Item key (default: Q) with the modifier to drop the entire selected stack (default: Control or Command, depending on OS). Location is always set to 0/0/0, Face is always set to -Y.
+
  | The payload is only present if the cookie exists on the client.
  |-
 
| 4
 
| Drop item
 
  | Triggered by using the Drop Item key (default: Q). Location is always set to 0/0/0, Face is always set to -Y.
 
 
  |-
 
  |-
  | 5
+
  | colspan="2"| Payload Length
  | Shoot arrow / finish eating
+
  | colspan="2"| {{Type|Optional}} {{Type|VarInt}}
  | Indicates that the currently held item should have its state updated such as eating food, pulling back bows, using buckets, etc. Location is always set to 0/0/0, Face is always set to -Y.
+
  | Length of the following byte array.
 
  |-
 
  |-
  | 6
+
  | colspan="2"| Payload
  | Swap item in hand
+
  | colspan="2"| {{Type|Optional}} {{Type|Byte Array}} (5120)
  | Used to swap or assign an item to the second hand. Location is always set to 0/0/0, Face is always set to -Y.
+
  | The data of the cookie, if any.
 
  |}
 
  |}
  
The Face field can be one of the following values, representing the face being hit:
+
==== Serverbound Plugin Message (play) ====
 +
 
 +
{{Main|Plugin channels}}
 +
 
 +
Mods and plugins can use this to send their data. Minecraft itself uses some [[plugin channel]]s. These internal channels are in the <code>minecraft</code> namespace.
 +
 
 +
More documentation on this: [https://dinnerbone.com/blog/2012/01/13/minecraft-plugin-channels-messaging/ https://dinnerbone.com/blog/2012/01/13/minecraft-plugin-channels-messaging/]
 +
 
 +
Note that the length of Data is known only from the packet length, since the packet has no length field of any kind.
  
 
{| class="wikitable"
 
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 
  |-
 
  |-
  ! Value
+
  | rowspan="2"| 0x12
  ! Offset
+
  | rowspan="2"| Play
  ! Face
+
  | rowspan="2"| Server
 +
| Channel
 +
| {{Type|Identifier}}
 +
| Name of the [[plugin channel]] used to send the data.
 
  |-
 
  |-
  | 0
+
  | Data
  | -Y
+
  | {{Type|Byte Array}} (32767)
| Bottom
+
  | Any data, depending on the channel. <code>minecraft:</code> channels are documented [[plugin channel|here]]. The length of this array must be inferred from the packet length.
|-
 
| 1
 
| +Y
 
| Top
 
|-
 
| 2
 
| -Z
 
| North
 
|-
 
| 3
 
| +Z
 
  | South
 
|-
 
| 4
 
| -X
 
| West
 
|-
 
| 5
 
| +X
 
| East
 
 
  |}
 
  |}
  
==== Player Command ====
+
In Notchian server, the maximum data length is 32767 bytes.
 +
 
 +
==== Debug Sample Subscription ====
 +
 
 +
Subscribes to the specified type of debug sample data, which is then sent periodically to the client via [[#Debug_Sample|Debug Sample]].
 +
 
 +
The subscription is retained for 10 seconds (the Notchian server checks that both 10.001 real-time seconds and 201 ticks have elapsed), after which the client is automatically unsubscribed. The Notchian client resends this packet every 5 seconds to keep up the subscription.
  
Sent by the client to indicate that it has performed certain actions: sneaking (crouching), sprinting, exiting a bed, jumping with a horse, and opening a horse's inventory while riding it.
+
The Notchian server only allows subscriptions from players that are server operators.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 8,177: Line 8,768:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="3"| 0x21
+
  | 0x13
  | rowspan="3"| Play
+
  | Play
  | rowspan="3"| Server
+
  | Server
  | Entity ID
+
  | Sample Type
  | VarInt
+
  | {{Type|VarInt}} {{Type|Enum}}
| Player ID
+
  | The type of debug sample to subscribe to. Can be one of the following:
|-
+
* 0 - Tick time
| Action ID
 
| VarInt Enum
 
  | The ID of the action, see below.
 
|-
 
| Jump Boost
 
| VarInt
 
| Only used by the “start jump with horse” action, in which case it ranges from 0 to 100. In all other cases it is 0.
 
 
  |}
 
  |}
  
Action ID can be one of the following values:
+
==== Edit Book ====
  
 
{| class="wikitable"
 
{| class="wikitable"
  ! ID
+
  ! Packet ID
  ! Action
+
  ! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 
  |-
 
  |-
  | 0
+
  | rowspan="5"| 0x14
  | Start sneaking
+
| rowspan="5"| Play
 +
| rowspan="5"| Server
 +
| Slot
 +
| {{Type|VarInt}}
 +
  | The hotbar slot where the written book is located
 
  |-
 
  |-
  | 1
+
  | Count
  | Stop sneaking
+
  | {{Type|VarInt}}
 +
| Number of elements in the following array. Maximum array size is 200.
 
  |-
 
  |-
  | 2
+
  | Entries
  | Leave bed
+
  | {{Type|Array}} (200) of {{Type|String}} (8192)
 +
| Text from each page. Maximum string length is 8192 chars.
 
  |-
 
  |-
  | 3
+
  | Has title
  | Start sprinting
+
  | {{Type|Boolean}}
 +
| If true, the next field is present. true if book is being signed, false if book is being edited.
 
  |-
 
  |-
  | 4
+
  | Title
  | Stop sprinting
+
  | {{Type|Optional}} {{Type|String}} (128)
|-
+
  | Title of book.
| 5
 
| Start jump with horse
 
|-
 
| 6
 
| Stop jump with horse
 
|-
 
| 7
 
| Open horse inventory
 
|-
 
| 8
 
  | Start flying with elytra
 
 
  |}
 
  |}
  
Leave bed is only sent when the “Leave Bed” button is clicked on the sleep GUI, not when waking up in the morning.
+
==== Query Entity Tag ====
  
Open horse inventory is only sent when pressing the inventory key (default: E) while on a horse — all other methods of opening a horse's inventory (involving right-clicking or shift-right-clicking it) do not use this packet.
+
Used when <kbd>F3</kbd>+<kbd>I</kbd> is pressed while looking at an entity.
 
 
==== Player Input ====
 
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 8,241: Line 8,823:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="3"| 0x22
+
  | rowspan="2"| 0x15
  | rowspan="3"| Play
+
  | rowspan="2"| Play
  | rowspan="3"| Server
+
  | rowspan="2"| Server
  | Sideways
+
  | Transaction ID
  | Float
+
  | {{Type|VarInt}}
  | Positive to the left of the player.
+
  | An incremental ID so that the client can verify that the response matches.
 
  |-
 
  |-
  | Forward
+
  | Entity ID
  | Float
+
  | {{Type|VarInt}}
| Positive forward.
+
  | The ID of the entity to query.
|-
 
| Flags
 
| Unsigned Byte
 
  | Bit mask. 0x1: jump, 0x2: unmount.
 
 
  |}
 
  |}
  
Also known as 'Input' packet.
+
==== Interact ====
  
==== Pong (play) ====
+
This packet is sent from the client to the server when the client attacks or right-clicks another entity (a player, minecart, etc).
  
Response to the clientbound packet ([[#Ping (play)|Ping]]) with the same id.
+
A Notchian server only accepts this packet if the entity being attacked/used is visible without obstruction and within a 4-unit radius of the player's position.
  
{| class="wikitable"
+
The target X, Y, and Z fields represent the difference between the vector location of the cursor at the time of the packet and the entity's position.
! Packet ID
 
! State
 
! Bound To
 
! Field Name
 
! Field Type
 
! Notes
 
|-
 
| 0x23
 
| Play
 
| Server
 
| ID
 
| Int
 
| id is the same as the ping packet
 
|}
 
  
==== Change Recipe Book Settings ====
+
Note that middle-click in creative mode is interpreted by the client and sent as a [[#Set Creative Mode Slot|Set Creative Mode Slot]] packet instead.
 
 
Replaces Recipe Book Data, type 1.
 
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 8,291: Line 8,853:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="3"| 0x24
+
  | rowspan="7"| 0x16
  | rowspan="3"| Play
+
  | rowspan="7"| Play
  | rowspan="3"| Server
+
  | rowspan="7"| Server
  | Book ID
+
  | Entity ID
  | VarInt Enum
+
  | {{Type|VarInt}}
  | 0: crafting, 1: furnace, 2: blast furnace, 3: smoker.
+
| The ID of the entity to interact. Note the special case described below.
 +
|-
 +
| Type
 +
| {{Type|VarInt}} {{Type|Enum}}
 +
  | 0: interact, 1: attack, 2: interact at.
 +
|-
 +
| Target X
 +
| {{Type|Optional}} {{Type|Float}}
 +
| Only if Type is interact at.
 
  |-
 
  |-
  | Book Open
+
  | Target Y
  | Boolean
+
  | {{Type|Optional}} {{Type|Float}}
  |
+
  | Only if Type is interact at.
 
  |-
 
  |-
  | Filter Active
+
  | Target Z
  | Boolean
+
  | {{Type|Optional}} {{Type|Float}}
  |
+
| Only if Type is interact at.
 +
|-
 +
| Hand
 +
| {{Type|Optional}} {{Type|VarInt}} {{Type|Enum}}
 +
| Only if Type is interact or interact at; 0: main hand, 1: off hand.
 +
|-
 +
| Sneaking
 +
| {{Type|Boolean}}
 +
| If the client is sneaking.
 +
|}
 +
 
 +
Interaction with the ender dragon is an odd special case characteristic of release deadline&ndash;driven design. 8 consecutive entity IDs following the dragon's ID (<var>id</var> + 1, <var>id</var> + 2, ..., <var>id</var> + 8) are reserved for the 8 hitboxes that make up the dragon:
 +
 
 +
{| class="wikitable"
 +
! ID offset
 +
! Description
 +
|-
 +
| 0
 +
| The dragon itself (never used in this packet)
 +
|-
 +
| 1
 +
| Head
 +
|-
 +
| 2
 +
| Neck
 +
|-
 +
| 3
 +
| Body
 +
|-
 +
| 4
 +
| Tail 1
 +
|-
 +
| 5
 +
| Tail 2
 +
|-
 +
| 6
 +
| Tail 3
 +
|-
 +
| 7
 +
| Wing 1
 +
|-
 +
| 8
 +
  | Wing 2
 
  |}
 
  |}
  
==== Set Seen Recipe ====
+
==== Jigsaw Generate ====
  
Sent when recipe is first seen in recipe book. Replaces Recipe Book Data, type 0.
+
Sent when Generate is pressed on the {{Minecraft Wiki|Jigsaw Block}} interface.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 8,319: Line 8,931:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | 0x25
+
  | rowspan="3"| 0x17
  | Play
+
  | rowspan="3"| Play
  | Server
+
  | rowspan="3"| Server
  | Recipe ID
+
  | Location
  | Identifier
+
| {{Type|Position}}
 +
| Block entity location.
 +
|-
 +
| Levels
 +
| {{Type|VarInt}}
 +
| Value of the levels slider/max depth to generate.
 +
  |-
 +
| Keep Jigsaws
 +
| {{Type|Boolean}}
 
  |
 
  |
 
  |}
 
  |}
  
==== Rename Item ====
+
==== Serverbound Keep Alive (play) ====
  
Sent as a player is renaming an item in an anvil (each keypress in the anvil UI sends a new Rename Item packet). If the new name is empty, then the item loses its custom name (this is different from setting the custom name to the normal name of the item). The item name may be no longer than 50 characters long, and if it is longer than that, then the rename is silently ignored.
+
The server will frequently send out a keep-alive (see [[#Clientbound Keep Alive (play)|Clientbound Keep Alive]]), each containing a random ID. The client must respond with the same packet.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 8,339: Line 8,959:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | 0x26
+
  | ''protocol:''<br/><code>0x18</code><br/><br/>''resource:''<br/><code>keep_alive</code>
 
  | Play
 
  | Play
 
  | Server
 
  | Server
  | Item name
+
| Keep Alive ID
  | String (32767)
+
| {{Type|Long}}
  | The new name of the item.
+
|
  |}
+
|}
 
+
 
==== Resource Pack Response (play) ====
+
==== Lock Difficulty ====
 
+
 
{| class="wikitable"
+
Must have at least op level 2 to use.  Appears to only be used on singleplayer; the difficulty buttons are still disabled in multiplayer.
  ! Packet ID
+
 
  ! State
+
{| class="wikitable"
  ! Bound To
+
! Packet ID
  ! Field Name
+
! State
  ! Field Type
+
! Bound To
  ! Notes
+
! Field Name
  |-
+
! Field Type
  | 0x27
+
! Notes
  | Play
+
|-
  | Server
+
| 0x19
  | Result
+
| Play
  | VarInt Enum
+
| Server
  | 0: successfully loaded, 1: declined, 2: failed download, 3: accepted.
+
| Locked
  |}
+
| {{Type|Boolean}}
 
+
|
==== Seen Advancements ====
+
|}
 
+
 
{| class="wikitable"
+
==== Set Player Position ====
  ! Packet ID
+
 
  ! State
+
Updates the player's XYZ position on the server.
  ! Bound To
+
 
  ! Field Name
+
If the player is in a vehicle, the position is ignored (but in case of [[#Set Player Position and Rotation|Set Player Position and Rotation]], the rotation is still used as normal). No validation steps other than value range clamping are performed in this case.
  ! Field Type
+
 
  ! Notes
+
If the player is sleeping, the position (or rotation) is not changed, and a [[#Synchronize Player Position|Synchronize Player Position]] is sent if the received position deviated from the server's view by more than a meter.
  |-
+
 
  | rowspan="2"| 0x28
+
The Notchian server silently clamps the x and z coordinates between -30,000,000 and 30,000,000, and the y coordinate between -20,000,000 and 20,000,000. A similar condition has historically caused a kick for "Illegal position"; this is no longer the case. However, infinite or NaN coordinates (or angles) still result in a kick for <code>multiplayer.disconnect.invalid_player_movement</code>.
  | rowspan="2"| Play
+
 
  | rowspan="2"| Server
+
As of 1.20.6, checking for moving too fast is achieved like this (sic):
  | Action
+
 
  | VarInt Enum
+
* Each server tick, the player's current position is stored.
  | 0: Opened tab, 1: Closed screen.
+
* When the player moves, the offset from the stored position to the requested position is computed (&Delta;x, &Delta;y, &Delta;z).
  |-
+
* The requested movement distance squared is computed as &Delta;x&sup2; + &Delta;y&sup2; + &Delta;z&sup2;.
  | Tab ID
+
* The baseline expected movement distance squared is computed based on  the player's server-side velocity as Vx&sup2; + Vy&sup2; + Vz&sup2;. The player's server-side velocity is a somewhat ill-defined quantity that includes among other things gravity, jump velocity and knockback, but ''not'' regular horizontal movement. A proper description would bring much of Minecraft's physics engine with it. It is accessible as the <code>Motion</code> NBT tag on the player entity.
  | Optional identifier
+
* The maximum permitted movement distance squared is computed as 100 (300 if the player is using an elytra), multiplied by the number of movement packets received since the last tick, including this one, unless that value is greater than 5, in which case no multiplier is applied.
  | Only present if action is Opened tab.
+
* If the requested movement distance squared minus the baseline distance squared is more than the maximum squared, the player is moving too fast.
  |}
+
 
 
+
If the player is moving too fast, it is logged that "<player> moved too quickly! " followed by the change in x, y, and z, and the player is teleported back to their current (before this packet) server-side position.
==== Select Trade ====
+
 
 
+
Checking for block collisions is achieved like this:
When a player selects a specific trade offered by a villager NPC.
+
 
 
+
* A temporary collision-checked move of the player is attempted from its current position to the requested one.
{| class="wikitable"
+
* The offset from the resulting position to the requested position is computed. If the absolute value of the offset on the y axis is less than 0.5, it (only the y component) is rounded down to 0.
  ! Packet ID
+
* If the magnitude of the offset is greater than 0.25 and the player isn't in creative or spectator mode, it is logged that "<player> moved wrongly!", and the player is teleported back to their current (before this packet) server-side position.
  ! State
+
* In addition, if the player's hitbox stationary at the requested position would intersect with a block, and they aren't in spectator mode, they are teleported back without a log message.
  ! Bound To
+
 
  ! Field Name
+
Checking for illegal flight is achieved like this:
  ! Field Type
+
 
  ! Notes
+
* When a movement packet is received, a flag indicating whether or not the player is floating mid-air is updated. The flag is set if the move test described above detected no collision below the player ''and'' the y component of the offset from the player's current position to the requested one is greater than -0.5, unless any of various conditions permitting flight (creative mode, elytra, levitation effect, etc., but not jumping) are met.
  |-
+
* Each server tick, it is checked if the flag has been set for more than 80 consecutive ticks. If so, and the player isn't currently sleeping, dead or riding a vehicle, they are kicked for <code>multiplayer.disconnect.flying</code>.
  | 0x29
+
 
  | Play
+
{| class="wikitable"
  | Server
+
! Packet ID
  | Selected slot
+
! State
  | VarInt
+
! Bound To
  | The selected slot in the players current (trading) inventory.
+
! Field Name
  |}
+
! Field Type
 +
! Notes
 +
|-
 +
| rowspan="4"| 0x1A
 +
| rowspan="4"| Play
 +
| rowspan="4"| Server
 +
| X
 +
| {{Type|Double}}
 +
| Absolute position.
 +
|-
 +
| Feet Y
 +
| {{Type|Double}}
 +
| Absolute feet position, normally Head Y - 1.62.
 +
|-
 +
| Z
 +
| {{Type|Double}}
 +
| Absolute position.
 +
|-
 +
| On Ground
 +
| {{Type|Boolean}}
 +
| True if the client is on the ground, false otherwise.
 +
|}
 +
 
 +
==== Set Player Position and Rotation ====
 +
 
 +
A combination of [[#Set Player Rotation|Move Player Rotation]] and [[#Set Player Position|Move Player Position]].
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 +
|-
 +
| rowspan="6"| 0x1B
 +
| rowspan="6"| Play
 +
| rowspan="6"| Server
 +
| X
 +
| {{Type|Double}}
 +
| Absolute position.
 +
|-
 +
| Feet Y
 +
| {{Type|Double}}
 +
| Absolute feet position, normally Head Y - 1.62.
 +
|-
 +
| Z
 +
| {{Type|Double}}
 +
| Absolute position.
 +
|-
 +
| Yaw
 +
| {{Type|Float}}
 +
| Absolute rotation on the X Axis, in degrees.
 +
|-
 +
| Pitch
 +
| {{Type|Float}}
 +
| Absolute rotation on the Y Axis, in degrees.
 +
|-
 +
| On Ground
 +
| {{Type|Boolean}}
 +
| True if the client is on the ground, false otherwise.
 +
|}
 +
 
 +
==== Set Player Rotation ====
 +
[[File:Minecraft-trig-yaw.png|thumb|The unit circle for yaw]]
 +
[[File:Yaw.png|thumb|The unit circle of yaw, redrawn]]
 +
 
 +
Updates the direction the player is looking in.
 +
 
 +
Yaw is measured in degrees, and does not follow classical trigonometry rules. The unit circle of yaw on the XZ-plane starts at (0, 1) and turns counterclockwise, with 90 at (-1, 0), 180 at (0,-1) and 270 at (1, 0). Additionally, yaw is not clamped to between 0 and 360 degrees; any number is valid, including negative numbers and numbers greater than 360.
 +
 
 +
Pitch is measured in degrees, where 0 is looking straight ahead, -90 is looking straight up, and 90 is looking straight down.
 +
 
 +
The yaw and pitch of player (in degrees), standing at point (x0, y0, z0) and looking towards point (x, y, z) can be calculated with:
 +
 
 +
dx = x-x0
 +
dy = y-y0
 +
dz = z-z0
 +
r = sqrt( dx*dx + dy*dy + dz*dz )
 +
yaw = -atan2(dx,dz)/PI*180
 +
if yaw < 0 then
 +
    yaw = 360 + yaw
 +
pitch = -arcsin(dy/r)/PI*180
 +
 
 +
You can get a unit vector from a given yaw/pitch via:
 +
 
 +
x = -cos(pitch) * sin(yaw)
 +
y = -sin(pitch)
 +
z =  cos(pitch) * cos(yaw)
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 +
|-
 +
| rowspan="3"| 0x1C
 +
| rowspan="3"| Play
 +
| rowspan="3"| Server
 +
| Yaw
 +
| {{Type|Float}}
 +
| Absolute rotation on the X Axis, in degrees.
 +
|-
 +
| Pitch
 +
| {{Type|Float}}
 +
| Absolute rotation on the Y Axis, in degrees.
 +
|-
 +
| On Ground
 +
| {{Type|Boolean}}
 +
| True if the client is on the ground, false otherwise.
 +
|}
 +
 
 +
==== Set Player On Ground ====
 +
 
 +
This packet as well as [[#Set Player Position|Set Player Position]], [[#Set Player Rotation|Set Player Rotation]], and [[#Set Player Position and Rotation|Set Player Position and Rotation]] are called the “serverbound movement packets”. Vanilla clients will send Move Player Position once every 20 ticks even for a stationary player.
 +
 
 +
This packet is used to indicate whether the player is on ground (walking/swimming), or airborne (jumping/falling).
 +
 
 +
When dropping from sufficient height, fall damage is applied when this state goes from false to true. The amount of damage applied is based on the point where it last changed from true to false. Note that there are several movement related packets containing this state.
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 +
|-
 +
| 0x1D
 +
| Play
 +
| Server
 +
| On Ground
 +
| {{Type|Boolean}}
 +
| True if the client is on the ground, false otherwise.
 +
|}
 +
 
 +
==== Move Vehicle ====
 +
 
 +
Sent when a player moves in a vehicle. Fields are the same as in [[#Set Player Position and Rotation|Set Player Position and Rotation]]. Note that all fields use absolute positioning and do not allow for relative positioning.
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 +
|-
 +
| rowspan="5"| 0x1E
 +
| rowspan="5"| Play
 +
| rowspan="5"| Server
 +
| X
 +
| {{Type|Double}}
 +
| Absolute position (X coordinate).
 +
|-
 +
| Y
 +
| {{Type|Double}}
 +
| Absolute position (Y coordinate).
 +
|-
 +
| Z
 +
| {{Type|Double}}
 +
| Absolute position (Z coordinate).
 +
|-
 +
| Yaw
 +
| {{Type|Float}}
 +
| Absolute rotation on the vertical axis, in degrees.
 +
|-
 +
| Pitch
 +
| {{Type|Float}}
 +
| Absolute rotation on the horizontal axis, in degrees.
 +
|}
 +
 
 +
==== Paddle Boat ====
 +
 
 +
Used to ''visually'' update whether boat paddles are turning.  The server will update the [[Entity_metadata#Boat|Boat entity metadata]] to match the values here.
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 +
|-
 +
| rowspan="2"| 0x1F
 +
| rowspan="2"| Play
 +
| rowspan="2"| Server
 +
| Left paddle turning
 +
| {{Type|Boolean}}
 +
|
 +
|-
 +
| Right paddle turning
 +
| {{Type|Boolean}}
 +
|
 +
|}
 +
 
 +
Right paddle turning is set to true when the left button or forward button is held, left paddle turning is set to true when the right button or forward button is held.
 +
 
 +
==== Pick Item ====
 +
 
 +
Used to swap out an empty space on the hotbar with the item in the given inventory slot.  The Notchian client uses this for pick block functionality (middle click) to retrieve items from the inventory.
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 +
|-
 +
| 0x20
 +
| Play
 +
| Server
 +
| Slot to use
 +
| {{Type|VarInt}}
 +
| See [[Inventory]].
 +
|}
 +
 
 +
The server first searches the player's hotbar for an empty slot, starting from the current slot and looping around to the slot before it.  If there are no empty slots, it starts a second search from the current slot and finds the first slot that does not contain an enchanted item.  If there still are no slots that meet that criteria, then the server uses the currently selected slot.
 +
 
 +
After finding the appropriate slot, the server swaps the items and sends 3 packets:
 +
 
 +
* [[#Set Container Slot|Set Container Slot]] with window ID set to -2, updating the chosen hotbar slot.
 +
* [[#Set Container Slot|Set Container Slot]] with window ID set to -2, updating the slot where the picked item used to be.
 +
* [[#Set Held Item (clientbound)|Set Held Item]], switching to the newly chosen slot.
 +
 
 +
==== Ping Request (play) ====
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 +
|-
 +
| 0x21
 +
| Play
 +
| Server
 +
| Payload
 +
| {{Type|Long}}
 +
| May be any number. Notchian clients use a system-dependent time value which is counted in milliseconds.
 +
|}
 +
 
 +
==== Place Recipe ====
 +
 
 +
This packet is sent when a player clicks a recipe in the crafting book that is craftable (white border).
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 +
|-
 +
| rowspan="3"| 0x22
 +
| rowspan="3"| Play
 +
| rowspan="3"| Server
 +
| Window ID
 +
| {{Type|Byte}}
 +
|
 +
|-
 +
| Recipe
 +
| {{Type|Identifier}}
 +
| A recipe ID.
 +
|-
 +
| Make all
 +
| {{Type|Boolean}}
 +
| Affects the amount of items processed; true if shift is down when clicked.
 +
|}
 +
 
 +
==== Player Abilities (serverbound) ====
 +
 
 +
The vanilla client sends this packet when the player starts/stops flying with the Flags parameter changed accordingly.
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 +
|-
 +
| 0x23
 +
| Play
 +
| Server
 +
| Flags
 +
| {{Type|Byte}}
 +
| Bit mask. 0x02: is flying.
 +
|}
 +
 
 +
==== Player Action ====
 +
 
 +
Sent when the player mines a block. A Notchian server only accepts digging packets with coordinates within a 6-unit radius between the center of the block and the player's eyes.
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 +
|-
 +
| rowspan="4"| 0x24
 +
| rowspan="4"| Play
 +
| rowspan="4"| Server
 +
| Status
 +
| {{Type|VarInt}} {{Type|Enum}}
 +
| The action the player is taking against the block (see below).
 +
|-
 +
| Location
 +
| {{Type|Position}}
 +
| Block position.
 +
|-
 +
| Face
 +
| {{Type|Byte}} {{Type|Enum}}
 +
| The face being hit (see below).
 +
|-
 +
| Sequence
 +
| {{Type|VarInt}}
 +
| Block change sequence number (see [[#Acknowledge Block Change]]).
 +
|}
 +
 
 +
Status can be one of seven values:
 +
 
 +
{| class="wikitable"
 +
! Value
 +
! Meaning
 +
! Notes
 +
|-
 +
| 0
 +
| Started digging
 +
| Sent when the player starts digging a block. If the block was instamined or the player is in creative mode, the client will ''not'' send Status = Finished digging, and will assume the server completed the destruction. To detect this, it is necessary to {{Minecraft Wiki|Breaking#Speed|calculate the block destruction speed}} server-side.
 +
|-
 +
| 1
 +
| Cancelled digging
 +
| Sent when the player lets go of the Mine Block key (default: left click). Face is always set to -Y.
 +
|-
 +
| 2
 +
| Finished digging
 +
| Sent when the client thinks it is finished.
 +
|-
 +
| 3
 +
| Drop item stack
 +
| Triggered by using the Drop Item key (default: Q) with the modifier to drop the entire selected stack (default: Control or Command, depending on OS). Location is always set to 0/0/0, Face is always set to -Y. Sequence is always set to 0.
 +
|-
 +
| 4
 +
| Drop item
 +
| Triggered by using the Drop Item key (default: Q). Location is always set to 0/0/0, Face is always set to -Y. Sequence is always set to 0.
 +
|-
 +
| 5
 +
| Shoot arrow / finish eating
 +
| Indicates that the currently held item should have its state updated such as eating food, pulling back bows, using buckets, etc. Location is always set to 0/0/0, Face is always set to -Y. Sequence is always set to 0.
 +
|-
 +
| 6
 +
| Swap item in hand
 +
| Used to swap or assign an item to the second hand. Location is always set to 0/0/0, Face is always set to -Y. Sequence is always set to 0.
 +
|}
 +
 
 +
The Face field can be one of the following values, representing the face being hit:
 +
 
 +
{| class="wikitable"
 +
|-
 +
! Value
 +
! Offset
 +
! Face
 +
|-
 +
| 0
 +
| -Y
 +
| Bottom
 +
|-
 +
| 1
 +
| +Y
 +
| Top
 +
|-
 +
| 2
 +
| -Z
 +
| North
 +
|-
 +
| 3
 +
| +Z
 +
| South
 +
|-
 +
| 4
 +
| -X
 +
| West
 +
|-
 +
| 5
 +
| +X
 +
| East
 +
|}
 +
 
 +
==== Player Command ====
 +
 
 +
Sent by the client to indicate that it has performed certain actions: sneaking (crouching), sprinting, exiting a bed, jumping with a horse, and opening a horse's inventory while riding it.
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 +
|-
 +
| rowspan="3"| 0x25
 +
| rowspan="3"| Play
 +
| rowspan="3"| Server
 +
| Entity ID
 +
| {{Type|VarInt}}
 +
| Player ID
 +
|-
 +
| Action ID
 +
| {{Type|VarInt}} {{Type|Enum}}
 +
| The ID of the action, see below.
 +
|-
 +
| Jump Boost
 +
| {{Type|VarInt}}
 +
| Only used by the “start jump with horse” action, in which case it ranges from 0 to 100. In all other cases it is 0.
 +
|}
 +
 
 +
Action ID can be one of the following values:
 +
 
 +
{| class="wikitable"
 +
! ID
 +
! Action
 +
|-
 +
| 0
 +
| Start sneaking
 +
|-
 +
| 1
 +
| Stop sneaking
 +
|-
 +
| 2
 +
| Leave bed
 +
|-
 +
| 3
 +
| Start sprinting
 +
|-
 +
| 4
 +
| Stop sprinting
 +
|-
 +
| 5
 +
| Start jump with horse
 +
|-
 +
| 6
 +
| Stop jump with horse
 +
|-
 +
| 7
 +
| Open vehicle inventory
 +
|-
 +
| 8
 +
| Start flying with elytra
 +
|}
 +
 
 +
Leave bed is only sent when the “Leave Bed” button is clicked on the sleep GUI, not when waking up in the morning.
 +
 
 +
Open vehicle inventory is only sent when pressing the inventory key (default: E) while on a horse or chest boat — all other methods of opening such an inventory (involving right-clicking or shift-right-clicking it) do not use this packet.
 +
 
 +
==== Player Input ====
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 +
|-
 +
| rowspan="3"| 0x26
 +
| rowspan="3"| Play
 +
| rowspan="3"| Server
 +
| Sideways
 +
| {{Type|Float}}
 +
| Positive to the left of the player.
 +
|-
 +
| Forward
 +
| {{Type|Float}}
 +
| Positive forward.
 +
|-
 +
| Flags
 +
| {{Type|Unsigned Byte}}
 +
| Bit mask. 0x1: jump, 0x2: unmount.
 +
|}
 +
 
 +
Also known as 'Input' packet.
 +
 
 +
==== Pong (play) ====
 +
 
 +
Response to the clientbound packet ([[#Ping (play)|Ping]]) with the same id.
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 +
|-
 +
| 0x27
 +
| Play
 +
| Server
 +
| ID
 +
| {{Type|Int}}
 +
| id is the same as the ping packet
 +
|}
 +
 
 +
==== Change Recipe Book Settings ====
 +
 
 +
Replaces Recipe Book Data, type 1.
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 +
|-
 +
| rowspan="3"| 0x28
 +
| rowspan="3"| Play
 +
| rowspan="3"| Server
 +
| Book ID
 +
| {{Type|VarInt}} {{Type|Enum}}
 +
| 0: crafting, 1: furnace, 2: blast furnace, 3: smoker.
 +
|-
 +
| Book Open
 +
| {{Type|Boolean}}
 +
|
 +
|-
 +
| Filter Active
 +
| {{Type|Boolean}}
 +
|
 +
|}
 +
 
 +
==== Set Seen Recipe ====
 +
 
 +
Sent when recipe is first seen in recipe book. Replaces Recipe Book Data, type 0.
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 +
|-
 +
| 0x29
 +
| Play
 +
| Server
 +
| Recipe ID
 +
| {{Type|Identifier}}
 +
|
 +
|}
 +
 
 +
==== Rename Item ====
 +
 
 +
Sent as a player is renaming an item in an anvil (each keypress in the anvil UI sends a new Rename Item packet). If the new name is empty, then the item loses its custom name (this is different from setting the custom name to the normal name of the item). The item name may be no longer than 50 characters long, and if it is longer than that, then the rename is silently ignored.
 +
 
 +
{| class="wikitable"
 +
! Packet ID
 +
! State
 +
! Bound To
 +
! Field Name
 +
! Field Type
 +
! Notes
 +
|-
 +
| 0x2A
 +
| Play
 +
| Server
 +
  | Item name
 +
  | {{Type|String}} (32767)
 +
  | The new name of the item.
 +
  |}
 +
 
 +
==== Resource Pack Response (play) ====
 +
 
 +
{| class="wikitable"
 +
  ! Packet ID
 +
  ! State
 +
  ! Bound To
 +
  ! Field Name
 +
  ! Field Type
 +
  ! Notes
 +
  |-
 +
  | rowspan="3" | 0x2B
 +
  | rowspan="3" | Play
 +
  | rowspan="3" | Server
 +
|-
 +
| UUID
 +
| {{Type|UUID}}
 +
| The unique identifier of the resource pack received in the [[#Add_Resource_Pack_(play)|Add Resource Pack (play)]] request.
 +
|-
 +
  | Result
 +
  | {{Type|VarInt}} {{Type|Enum}}
 +
| Result ID (see below).
 +
|}
 +
 
 +
Result can be one of the following values:
 +
 
 +
 
 +
{| class="wikitable"
 +
! ID
 +
! Result
 +
|-
 +
  | 0
 +
| Successfully downloaded
 +
|-
 +
| 1
 +
| Declined
 +
|-
 +
| 2
 +
| Failed to download
 +
|-
 +
| 3
 +
| Accepted
 +
|-
 +
| 4
 +
| Downloaded
 +
|-
 +
| 5
 +
| Invalid URL
 +
|-
 +
| 6
 +
| Failed to reload
 +
|-
 +
| 7
 +
| Discarded
 +
  |}
 +
 
 +
==== Seen Advancements ====
 +
 
 +
{| class="wikitable"
 +
  ! Packet ID
 +
  ! State
 +
  ! Bound To
 +
  ! Field Name
 +
  ! Field Type
 +
  ! Notes
 +
  |-
 +
  | rowspan="2"| 0x2C
 +
  | rowspan="2"| Play
 +
  | rowspan="2"| Server
 +
  | Action
 +
  | {{Type|VarInt}} {{Type|Enum}}
 +
  | 0: Opened tab, 1: Closed screen.
 +
  |-
 +
  | Tab ID
 +
  | {{Type|Optional}} {{Type|Identifier}}
 +
  | Only present if action is Opened tab.
 +
  |}
 +
 
 +
==== Select Trade ====
 +
 
 +
When a player selects a specific trade offered by a villager NPC.
 +
 
 +
{| class="wikitable"
 +
  ! Packet ID
 +
  ! State
 +
  ! Bound To
 +
  ! Field Name
 +
  ! Field Type
 +
  ! Notes
 +
  |-
 +
  | 0x2D
 +
  | Play
 +
  | Server
 +
  | Selected slot
 +
  | {{Type|VarInt}}
 +
  | The selected slot in the players current (trading) inventory.
 +
  |}
  
 
==== Set Beacon Effect ====
 
==== Set Beacon Effect ====
Line 8,419: Line 9,711:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="5"| 0x2A
+
  | rowspan="5"| 0x2E
 
  | rowspan="5"| Play
 
  | rowspan="5"| Play
 
  | rowspan="5"| Server
 
  | rowspan="5"| Server
 
  |-
 
  |-
 
  | Has Primary Effect
 
  | Has Primary Effect
  | Boolean
+
  | {{Type|Boolean}}
 
  |-
 
  |-
 
  | Primary Effect
 
  | Primary Effect
  | VarInt
+
  | {{Type|Optional}} {{Type|VarInt}}
 
  | A [https://minecraft.wiki/w/Potion#ID Potion ID].
 
  | A [https://minecraft.wiki/w/Potion#ID Potion ID].
 
  |-
 
  |-
 
  | Has Secondary Effect
 
  | Has Secondary Effect
  | Boolean
+
  | {{Type|Boolean}}
 
  |
 
  |
 
  |-
 
  |-
 
  | Secondary Effect
 
  | Secondary Effect
  | VarInt
+
  | {{Type|Optional}} {{Type|VarInt}}
 
  | A [https://minecraft.wiki/w/Potion#ID Potion ID].
 
  | A [https://minecraft.wiki/w/Potion#ID Potion ID].
 
  |}
 
  |}
  
==== Set Held Item ====
+
==== Set Held Item (serverbound) ====
  
Sent when the player changes the slot selection
+
Sent when the player changes the slot selection.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 8,451: Line 9,743:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | 0x2B
+
  | 0x2F
 
  | Play
 
  | Play
 
  | Server
 
  | Server
 
  | Slot
 
  | Slot
  | Short
+
  | {{Type|Short}}
 
  | The slot which the player has selected (0–8).
 
  | The slot which the player has selected (0–8).
 
  |}
 
  |}
Line 8,469: Line 9,761:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="5"| 0x2C
+
  | rowspan="5"| 0x30
 
  | rowspan="5"| Play
 
  | rowspan="5"| Play
 
  | rowspan="5"| Server
 
  | rowspan="5"| Server
 
  |-
 
  |-
 
  | Location
 
  | Location
  | Position
+
  | {{Type|Position}}
 
  |
 
  |
 
  |-
 
  |-
 
  | Command
 
  | Command
  | String (32767)
+
  | {{Type|String}} (32767)
 
  |
 
  |
 
  |-
 
  |-
  | Mode || VarInt Enum || One of SEQUENCE (0), AUTO (1), or REDSTONE (2).
+
  | Mode || {{Type|VarInt}} {{Type|Enum}} || One of SEQUENCE (0), AUTO (1), or REDSTONE (2).
 
  |-
 
  |-
 
  | Flags
 
  | Flags
  | Byte
+
  | {{Type|Byte}}
 
  | 0x01: Track Output (if false, the output of the previous command will not be stored within the command block); 0x02: Is conditional; 0x04: Automatic.
 
  | 0x01: Track Output (if false, the output of the previous command will not be stored within the command block); 0x02: Is conditional; 0x04: Automatic.
 
  |}
 
  |}
Line 8,498: Line 9,790:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="3"| 0x2D
+
  | rowspan="3"| 0x31
 
  | rowspan="3"| Play
 
  | rowspan="3"| Play
 
  | rowspan="3"| Server
 
  | rowspan="3"| Server
 
  | Entity ID
 
  | Entity ID
  | VarInt
+
  | {{Type|VarInt}}
 
  |
 
  |
 
  |-
 
  |-
 
  | Command
 
  | Command
  | String (32767)
+
  | {{Type|String}} (32767)
 
  |
 
  |
 
  |-
 
  |-
 
  | Track Output
 
  | Track Output
  | Boolean
+
  | {{Type|Boolean}}
 
  | If false, the output of the previous command will not be stored within the command block.
 
  | If false, the output of the previous command will not be stored within the command block.
 
  |}
 
  |}
Line 8,530: Line 9,822:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="2"| 0x2E
+
  | rowspan="2"| 0x32
 
  | rowspan="2"| Play
 
  | rowspan="2"| Play
 
  | rowspan="2"| Server
 
  | rowspan="2"| Server
 
  | Slot
 
  | Slot
  | Short
+
  | {{Type|Short}}
 
  | Inventory slot.
 
  | Inventory slot.
 
  |-
 
  |-
 
  | Clicked Item
 
  | Clicked Item
  | [[Slot Data|Slot]]
+
  | {{Type|Slot}}
 
  |
 
  |
 
  |}
 
  |}
Line 8,554: Line 9,846:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="6"| 0x2F
+
  | rowspan="8"| 0x33
  | rowspan="6"| Play
+
  | rowspan="8"| Play
  | rowspan="6"| Server
+
  | rowspan="8"| Server
 
  | Location
 
  | Location
  | Position
+
  | {{Type|Position}}
 
  | Block entity location
 
  | Block entity location
 
  |-
 
  |-
 
  | Name
 
  | Name
  | Identifier
+
  | {{Type|Identifier}}
 
  |
 
  |
 
  |-
 
  |-
 
  | Target
 
  | Target
  | Identifier
+
  | {{Type|Identifier}}
 
  |
 
  |
 
  |-
 
  |-
 
  | Pool
 
  | Pool
  | Identifier
+
  | {{Type|Identifier}}
 
  |
 
  |
 
  |-
 
  |-
 
  | Final state
 
  | Final state
  | String (32767)
+
  | {{Type|String}} (32767)
 
  | "Turns into" on the GUI, <code>final_state</code> in NBT.
 
  | "Turns into" on the GUI, <code>final_state</code> in NBT.
 
  |-
 
  |-
 
  | Joint type
 
  | Joint type
  | String (32767)
+
  | {{Type|String}} (32767)
 
  | <code>rollable</code> if the attached piece can be rotated, else <code>aligned</code>.
 
  | <code>rollable</code> if the attached piece can be rotated, else <code>aligned</code>.
 +
|-
 +
| Selection priority
 +
| {{Type|VarInt}}
 +
|
 +
|-
 +
| Placement priority
 +
| {{Type|VarInt}}
 +
|
 
  |}
 
  |}
  
Line 8,592: Line 9,892:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="17"| 0x30
+
  | rowspan="17"| 0x34
 
  | rowspan="17"| Play
 
  | rowspan="17"| Play
 
  | rowspan="17"| Server
 
  | rowspan="17"| Server
 
  |-
 
  |-
 
  | Location
 
  | Location
  | Position
+
  | {{Type|Position}}
 
  | Block entity location.
 
  | Block entity location.
 
  |-
 
  |-
 
  | Action
 
  | Action
  | VarInt Enum
+
  | {{Type|VarInt}} {{Type|Enum}}
 
  | An additional action to perform beyond simply saving the given data; see below.
 
  | An additional action to perform beyond simply saving the given data; see below.
 
  |-
 
  |-
 
  | Mode
 
  | Mode
  | VarInt Enum
+
  | {{Type|VarInt}} {{Type|Enum}}
 
  | One of SAVE (0), LOAD (1), CORNER (2), DATA (3).
 
  | One of SAVE (0), LOAD (1), CORNER (2), DATA (3).
 
  |-
 
  |-
 
  | Name
 
  | Name
  | String (32767)
+
  | {{Type|String}} (32767)
 
  |
 
  |
 
  |-
 
  |-
  | Offset X || Byte
+
  | Offset X || {{Type|Byte}}
 
  | Between -48 and 48.
 
  | Between -48 and 48.
 
  |-
 
  |-
  | Offset Y || Byte
+
  | Offset Y || {{Type|Byte}}
 
  | Between -48 and 48.
 
  | Between -48 and 48.
 
  |-
 
  |-
  | Offset Z || Byte
+
  | Offset Z || {{Type|Byte}}
 
  | Between -48 and 48.
 
  | Between -48 and 48.
 
  |-
 
  |-
  | Size X || Byte
+
  | Size X || {{Type|Byte}}
 
  | Between 0 and 48.
 
  | Between 0 and 48.
 
  |-
 
  |-
  | Size Y || Byte
+
  | Size Y || {{Type|Byte}}
 
  | Between 0 and 48.
 
  | Between 0 and 48.
 
  |-
 
  |-
  | Size Z || Byte
+
  | Size Z || {{Type|Byte}}
 
  | Between 0 and 48.
 
  | Between 0 and 48.
 
  |-
 
  |-
 
  | Mirror
 
  | Mirror
  | VarInt Enum
+
  | {{Type|VarInt}} {{Type|Enum}}
 
  | One of NONE (0), LEFT_RIGHT (1), FRONT_BACK (2).
 
  | One of NONE (0), LEFT_RIGHT (1), FRONT_BACK (2).
 
  |-
 
  |-
 
  | Rotation
 
  | Rotation
  | VarInt Enum
+
  | {{Type|VarInt}} {{Type|Enum}}
 
  | One of NONE (0), CLOCKWISE_90 (1), CLOCKWISE_180 (2), COUNTERCLOCKWISE_90 (3).
 
  | One of NONE (0), CLOCKWISE_90 (1), CLOCKWISE_180 (2), COUNTERCLOCKWISE_90 (3).
 
  |-
 
  |-
 
  | Metadata
 
  | Metadata
  | String (128)
+
  | {{Type|String}} (128)
 
  |
 
  |
 
  |-
 
  |-
 
  | Integrity
 
  | Integrity
  | Float
+
  | {{Type|Float}}
 
  | Between 0 and 1.
 
  | Between 0 and 1.
 
  |-
 
  |-
 
  |Seed
 
  |Seed
  |VarLong
+
  |{{Type|VarLong}}
 
  |
 
  |
 
  |-
 
  |-
 
  | Flags
 
  | Flags
  | Byte
+
  | {{Type|Byte}}
 
  | 0x01: Ignore entities; 0x02: Show air; 0x04: Show bounding box.
 
  | 0x01: Ignore entities; 0x02: Show air; 0x04: Show bounding box.
 
  |}
 
  |}
Line 8,678: Line 9,978:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="6"| 0x31
+
  | rowspan="6"| 0x35
 
  | rowspan="6"| Play
 
  | rowspan="6"| Play
 
  | rowspan="6"| Server
 
  | rowspan="6"| Server
 
  | Location
 
  | Location
  | Position
+
  | {{Type|Position}}
 
  | Block Coordinates.
 
  | Block Coordinates.
 
  |-
 
  |-
 
  | Is Front Text
 
  | Is Front Text
  | Boolean
+
  | {{Type|Boolean}}
 
  | Whether the updated text is in front or on the back of the sign
 
  | Whether the updated text is in front or on the back of the sign
 
  |-
 
  |-
 
  | Line 1
 
  | Line 1
  | String (384)
+
  | {{Type|String}} (384)
 
  | First line of text in the sign.
 
  | First line of text in the sign.
 
  |-
 
  |-
 
  | Line 2
 
  | Line 2
  | String (384)
+
  | {{Type|String}} (384)
 
  | Second line of text in the sign.
 
  | Second line of text in the sign.
 
  |-
 
  |-
 
  | Line 3
 
  | Line 3
  | String (384)
+
  | {{Type|String}} (384)
 
  | Third line of text in the sign.
 
  | Third line of text in the sign.
 
  |-
 
  |-
 
  | Line 4
 
  | Line 4
  | String (384)
+
  | {{Type|String}} (384)
 
  | Fourth line of text in the sign.
 
  | Fourth line of text in the sign.
 
  |}
 
  |}
Line 8,718: Line 10,018:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | 0x32
+
  | 0x36
 
  | Play
 
  | Play
 
  | Server
 
  | Server
 
  | Hand
 
  | Hand
  | VarInt Enum
+
  | {{Type|VarInt}} {{Type|Enum}}
 
  | Hand used for the animation. 0: main hand, 1: off hand.
 
  | Hand used for the animation. 0: main hand, 1: off hand.
 
  |}
 
  |}
Line 8,740: Line 10,040:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | 0x33
+
  | 0x37
 
  | Play
 
  | Play
 
  | Server
 
  | Server
 
  | Target Player
 
  | Target Player
  | UUID
+
  | {{Type|UUID}}
 
  | UUID of the player to teleport to (can also be an entity UUID).
 
  | UUID of the player to teleport to (can also be an entity UUID).
 
  |}
 
  |}
Line 8,759: Line 10,059:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="8"| 0x34
+
  | rowspan="8"| 0x38
 
  | rowspan="8"| Play
 
  | rowspan="8"| Play
 
  | rowspan="8"| Server
 
  | rowspan="8"| Server
 
  | Hand
 
  | Hand
  | VarInt Enum
+
  | {{Type|VarInt}} {{Type|Enum}}
 
  | The hand from which the block is placed; 0: main hand, 1: off hand.
 
  | The hand from which the block is placed; 0: main hand, 1: off hand.
 
  |-
 
  |-
 
  | Location
 
  | Location
  | Position
+
  | {{Type|Position}}
 
  | Block position.
 
  | Block position.
 
  |-
 
  |-
 
  | Face
 
  | Face
  | VarInt Enum
+
  | {{Type|VarInt}} {{Type|Enum}}
 
  | The face on which the block is placed (as documented at [[#Player Action|Player Action]]).
 
  | The face on which the block is placed (as documented at [[#Player Action|Player Action]]).
 
  |-
 
  |-
 
  | Cursor Position X
 
  | Cursor Position X
  | Float
+
  | {{Type|Float}}
 
  | The position of the crosshair on the block, from 0 to 1 increasing from west to east.
 
  | The position of the crosshair on the block, from 0 to 1 increasing from west to east.
 
  |-
 
  |-
 
  | Cursor Position Y
 
  | Cursor Position Y
  | Float
+
  | {{Type|Float}}
 
  | The position of the crosshair on the block, from 0 to 1 increasing from bottom to top.
 
  | The position of the crosshair on the block, from 0 to 1 increasing from bottom to top.
 
  |-
 
  |-
 
  | Cursor Position Z
 
  | Cursor Position Z
  | Float
+
  | {{Type|Float}}
 
  | The position of the crosshair on the block, from 0 to 1 increasing from north to south.
 
  | The position of the crosshair on the block, from 0 to 1 increasing from north to south.
 
  |-
 
  |-
 
  | Inside block
 
  | Inside block
  | Boolean
+
  | {{Type|Boolean}}
 
  | True when the player's head is inside of a block.
 
  | True when the player's head is inside of a block.
 
  |-
 
  |-
 
  | Sequence
 
  | Sequence
  | VarInt
+
  | {{Type|VarInt}}
 +
| Block change sequence number (see [[#Acknowledge Block Change]]).
 
  |}
 
  |}
  
Line 8,812: Line 10,113:
 
  ! Notes
 
  ! Notes
 
  |-
 
  |-
  | rowspan="2"| 0x35
+
  | rowspan="4"| 0x39
  | rowspan="2"| Play
+
  | rowspan="4"| Play
  | rowspan="2"| Server
+
  | rowspan="4"| Server
 
  | Hand
 
  | Hand
  | VarInt Enum
+
  | {{Type|VarInt}} {{Type|Enum}}
 
  | Hand used for the animation. 0: main hand, 1: off hand.
 
  | Hand used for the animation. 0: main hand, 1: off hand.
 
  |-
 
  |-
 
  | Sequence
 
  | Sequence
  | VarInt
+
  | {{Type|VarInt}}
 +
| Block change sequence number (see [[#Acknowledge Block Change]]).
 +
|-
 +
| Yaw
 +
| {{Type|Float}}
 +
| Player head rotation along the Y-Axis.
 +
|-
 +
| Pitch
 +
| {{Type|Float}}
 +
| Player head rotation along the X-Axis.
 
  |}
 
  |}
  
 
[[Category:Protocol Details]]
 
[[Category:Protocol Details]]
 
[[Category:Minecraft Modern]]
 
[[Category:Minecraft Modern]]

Latest revision as of 00:48, 16 October 2024

Heads up!

This article is about the protocol for a stable release of Minecraft Java Edition (1.21.1, protocol 767). For the Java Edition pre-releases, see Pre-release protocol. For the incomplete Bedrock Edition docs, see Bedrock Protocol. For the old Pocket Edition, see Pocket Edition Protocol Documentation.

This page presents a dissection of the current Minecraft protocol.

If you're having trouble, check out the FAQ or ask for help in the IRC channel #mcdevs on irc.libera.chat (More Information).

Note: While you may use the contents of this page without restriction to create servers, clients, bots, etc; substantial reproductions of this page must be attributed IAW CC BY-SA 4.0.

The changes between versions may be viewed at Protocol History.

Contents

Definitions

The Minecraft server accepts connections from TCP clients and communicates with them using packets. A packet is a sequence of bytes sent over the TCP connection. The meaning of a packet depends both on its packet ID and the current state of the connection. The initial state of each connection is Handshaking, and state is switched using the packets Handshake and Login Success.

Data types

All data sent over the network (except for VarInt and VarLong) is big-endian, that is the bytes are sent from most significant byte to least significant byte. The majority of everyday computers are little-endian, therefore it may be necessary to change the endianness before sending data over the network.


Name Size (bytes) Encodes Notes
Boolean 1 Either false or true True is encoded as 0x01, false as 0x00.
Byte 1 An integer between -128 and 127 Signed 8-bit integer, two's complement
Unsigned Byte 1 An integer between 0 and 255 Unsigned 8-bit integer
Short 2 An integer between -32768 and 32767 Signed 16-bit integer, two's complement
Unsigned Short 2 An integer between 0 and 65535 Unsigned 16-bit integer
Int 4 An integer between -2147483648 and 2147483647 Signed 32-bit integer, two's complement
Long 8 An integer between -9223372036854775808 and 9223372036854775807 Signed 64-bit integer, two's complement
Float 4 A single-precision 32-bit IEEE 754 floating point number
Double 8 A double-precision 64-bit IEEE 754 floating point number
String (n) ≥ 1
≤ (n×3) + 3
A sequence of Unicode scalar values UTF-8 string prefixed with its size in bytes as a VarInt. Maximum length of n characters, which varies by context. The encoding used on the wire is regular UTF-8, not Java's "slight modification". However, the length of the string for purposes of the length limit is its number of UTF-16 code units, that is, scalar values > U+FFFF are counted as two. Up to n × 3 bytes can be used to encode a UTF-8 string comprising n code units when converted to UTF-16, and both of those limits are checked. Maximum n value is 32767. The + 3 is due to the max size of a valid length VarInt.
Text Component Varies See Text formatting#Text components Encoded as a NBT Tag, with the type of tag used depending on the case:
  • As a String Tag: For components only containing text (no styling, no events etc.).
  • As a Compound Tag: Every other case.
JSON Text Component ≥ 1
≤ (262144×3) + 3
See Text formatting#Text components The maximum permitted length when decoding is 262144, but the Notchian server since 1.20.3 refuses to encode longer than 32767. This may be a bug.
Identifier ≥ 1
≤ (32767×3) + 3
See Identifier below Encoded as a String with max length of 32767.
VarInt ≥ 1
≤ 5
An integer between -2147483648 and 2147483647 Variable-length data encoding a two's complement signed 32-bit integer; more info in their section
VarLong ≥ 1
≤ 10
An integer between -9223372036854775808 and 9223372036854775807 Variable-length data encoding a two's complement signed 64-bit integer; more info in their section
Entity Metadata Varies Miscellaneous information about an entity See Entity_metadata#Entity Metadata Format
Slot Varies An item stack in an inventory or container See Slot Data
NBT Varies Depends on context See NBT
Position 8 An integer/block position: x (-33554432 to 33554431), z (-33554432 to 33554431), y (-2048 to 2047) x as a 26-bit integer, followed by z as a 26-bit integer, followed by y as a 12-bit integer (all signed, two's complement). See also the section below.
Angle 1 A rotation angle in steps of 1/256 of a full turn Whether or not this is signed does not matter, since the resulting angles are the same.
UUID 16 A UUID Encoded as an unsigned 128-bit integer (or two unsigned 64-bit integers: the most significant 64 bits and then the least significant 64 bits)
BitSet Varies See #BitSet below A length-prefixed bit set.
Fixed BitSet (n) ceil(n / 8) See #Fixed BitSet below A bit set with a fixed length of n bits.
Optional X 0 or size of X A field of type X, or nothing Whether or not the field is present must be known from the context.
Array of X count times size of X Zero or more fields of type X The count must be known from the context.
X Enum size of X A specific value from a given list The list of possible values and how each is encoded as an X must be known from the context. An invalid value sent by either side will usually result in the client being disconnected with an error or even crashing.
Byte Array Varies Depends on context This is just a sequence of zero or more bytes, its meaning should be explained somewhere else, e.g. in the packet description. The length must also be known from the context.

Identifier

Identifiers are a namespaced location, in the form of minecraft:thing. If the namespace is not provided, it defaults to minecraft (i.e. thing is minecraft:thing). Custom content should always be in its own namespace, not the default one. Both the namespace and value can use all lowercase alphanumeric characters (a-z and 0-9), dot (.), dash (-), and underscore (_). In addition, values can use slash (/). The naming convention is lower_case_with_underscores. More information. For ease of determining whether a namespace or value is valid, here are regular expressions for each:

  • Namespace: [a-z0-9.-_]
  • Value: [a-z0-9.-_/]

VarInt and VarLong

Variable-length format such that smaller numbers use fewer bytes. These are very similar to Protocol Buffer Varints: the 7 least significant bits are used to encode the value and the most significant bit indicates whether there's another byte after it for the next part of the number. The least significant group is written first, followed by each of the more significant groups; thus, VarInts are effectively little endian (however, groups are 7 bits, not 8).

VarInts are never longer than 5 bytes, and VarLongs are never longer than 10 bytes. Within these limits, unnecessarily long encodings (e.g. 81 00 to encode 1) are allowed.

Pseudocode to read and write VarInts and VarLongs:

private static final int SEGMENT_BITS = 0x7F;
private static final int CONTINUE_BIT = 0x80;
public int readVarInt() {
    int value = 0;
    int position = 0;
    byte currentByte;

    while (true) {
        currentByte = readByte();
        value |= (currentByte & SEGMENT_BITS) << position;

        if ((currentByte & CONTINUE_BIT) == 0) break;

        position += 7;

        if (position >= 32) throw new RuntimeException("VarInt is too big");
    }

    return value;
}
public long readVarLong() {
    long value = 0;
    int position = 0;
    byte currentByte;

    while (true) {
        currentByte = readByte();
        value |= (long) (currentByte & SEGMENT_BITS) << position;

        if ((currentByte & CONTINUE_BIT) == 0) break;

        position += 7;

        if (position >= 64) throw new RuntimeException("VarLong is too big");
    }

    return value;
}
public void writeVarInt(int value) {
    while (true) {
        if ((value & ~SEGMENT_BITS) == 0) {
            writeByte(value);
            return;
        }

        writeByte((value & SEGMENT_BITS) | CONTINUE_BIT);

        // Note: >>> means that the sign bit is shifted with the rest of the number rather than being left alone
        value >>>= 7;
    }
}
public void writeVarLong(long value) {
    while (true) {
        if ((value & ~((long) SEGMENT_BITS)) == 0) {
            writeByte(value);
            return;
        }

        writeByte((value & SEGMENT_BITS) | CONTINUE_BIT);

        // Note: >>> means that the sign bit is shifted with the rest of the number rather than being left alone
        value >>>= 7;
    }
}

Warning.png Note Minecraft's VarInts are identical to LEB128 with the slight change of throwing a exception if it goes over a set amount of bytes.

Warning.png Note that Minecraft's VarInts are not encoded using Protocol Buffers; it's just similar. If you try to use Protocol Buffers Varints with Minecraft's VarInts, you'll get incorrect results in some cases. The major differences:

  • Minecraft's VarInts are all signed, but do not use the ZigZag encoding. Protocol buffers have 3 types of Varints: uint32 (normal encoding, unsigned), sint32 (ZigZag encoding, signed), and int32 (normal encoding, signed). Minecraft's are the int32 variety. Because Minecraft uses the normal encoding instead of ZigZag encoding, negative values always use the maximum number of bytes.
  • Minecraft's VarInts are never longer than 5 bytes and its VarLongs will never be longer than 10 bytes, while Protocol Buffer Varints will always use 10 bytes when encoding negative numbers, even if it's an int32.

Sample VarInts:

Value Hex bytes Decimal bytes
0 0x00 0
1 0x01 1
2 0x02 2
127 0x7f 127
128 0x80 0x01 128 1
255 0xff 0x01 255 1
25565 0xdd 0xc7 0x01 221 199 1
2097151 0xff 0xff 0x7f 255 255 127
2147483647 0xff 0xff 0xff 0xff 0x07 255 255 255 255 7
-1 0xff 0xff 0xff 0xff 0x0f 255 255 255 255 15
-2147483648 0x80 0x80 0x80 0x80 0x08 128 128 128 128 8

Sample VarLongs:

Value Hex bytes Decimal bytes
0 0x00 0
1 0x01 1
2 0x02 2
127 0x7f 127
128 0x80 0x01 128 1
255 0xff 0x01 255 1
2147483647 0xff 0xff 0xff 0xff 0x07 255 255 255 255 7
9223372036854775807 0xff 0xff 0xff 0xff 0xff 0xff 0xff 0xff 0x7f 255 255 255 255 255 255 255 255 127
-1 0xff 0xff 0xff 0xff 0xff 0xff 0xff 0xff 0xff 0x01 255 255 255 255 255 255 255 255 255 1
-2147483648 0x80 0x80 0x80 0x80 0xf8 0xff 0xff 0xff 0xff 0x01 128 128 128 128 248 255 255 255 255 1
-9223372036854775808 0x80 0x80 0x80 0x80 0x80 0x80 0x80 0x80 0x80 0x01 128 128 128 128 128 128 128 128 128 1

Position

Note: What you are seeing here is the latest version of the Data types article, but the position type was different before 1.14.

64-bit value split into three signed integer parts:

  • x: 26 MSBs
  • z: 26 middle bits
  • y: 12 LSBs

For example, a 64-bit position can be broken down as follows:

Example value (big endian): 01000110000001110110001100 10110000010101101101001000 001100111111

  • The red value is the X coordinate, which is 18357644 in this example.
  • The blue value is the Z coordinate, which is -20882616 in this example.
  • The green value is the Y coordinate, which is 831 in this example.

Encoded as follows:

((x & 0x3FFFFFF) << 38) | ((z & 0x3FFFFFF) << 12) | (y & 0xFFF)

And decoded as:

val = read_long();
x = val >> 38;
y = val << 52 >> 52;
z = val << 26 >> 38;

Note: The above assumes that the right shift operator sign extends the value (this is called an arithmetic shift), so that the signedness of the coordinates is preserved. In many languages, this requires the integer type of val to be signed. In the absence of such an operator, the following may be useful:

if x >= 1 << 25 { x -= 1 << 26 }
if y >= 1 << 11 { y -= 1 << 12 }
if z >= 1 << 25 { z -= 1 << 26 }

Fixed-point numbers

Some fields may be stored as fixed-point numbers, where a certain number of bits represent the signed integer part (number to the left of the decimal point) and the rest represent the fractional part (to the right). Floating point numbers (float and double), in contrast, keep the number itself (mantissa) in one chunk, while the location of the decimal point (exponent) is stored beside it. Essentially, while fixed-point numbers have lower range than floating point numbers, their fractional precision is greater for higher values.

Prior to version 1.9 a fixed-point format with 5 fraction bits and 27 integer bits was used to send entity positions to the client. Some uses of fixed point remain in modern versions, but they differ from that format.

Most programming languages lack support for fractional integers directly, but you can represent them as integers. The following C or Java-like pseudocode converts a double to a fixed-point integer with n fraction bits:

 x_fixed = (int)(x_double * (1 << n));

And back again:

 x_double = (double)x_fixed / (1 << n);

Bit sets

The types BitSet and Fixed BitSet represent packed lists of bits. The Notchian implementation uses Java's BitSet class.

BitSet

Bit sets of type BitSet are prefixed by their length in longs.

Field Name Field Type Meaning
Length VarInt Number of longs in the following array. May be 0 (if no bits are set).
Data Array of Long A packed representation of the bit set as created by BitSet.toLongArray.

The ith bit is set when (Data[i / 64] & (1 << (i % 64))) != 0, where i starts at 0.

Fixed BitSet

Bit sets of type Fixed BitSet (n) have a fixed length of n bits, encoded as ceil(n / 8) bytes. Note that this is different from BitSet, which uses longs.

Field Name Field Type Meaning
Data Byte Array (n) A packed representation of the bit set as created by BitSet.toByteArray, padded with zeroes at the end to fit the specified length.

The ith bit is set when (Data[i / 8] & (1 << (i % 8))) != 0, where i starts at 0. This encoding is not equivalent to the long array in BitSet.


Other definitions

Term Definition
Player When used in the singular, Player always refers to the client connected to the server.
Entity Entity refers to any item, player, mob, minecart or boat etc. See the Minecraft Wiki article for a full list.
EID An EID — or Entity ID — is a 4-byte sequence used to identify a specific entity. An entity's EID is unique on the entire server.
XYZ In this document, the axis names are the same as those shown in the debug screen (F3). Y points upwards, X points east, and Z points south.
Meter The meter is Minecraft's base unit of length, equal to the length of a vertex of a solid block. The term “block” may be used to mean “meter” or “cubic meter”.
Registry A table describing static, gameplay-related objects of some kind, such as the types of entities, block states or biomes. The entries of a registry are typically associated with textual or numeric identifiers, or both.

Minecraft has a unified registry system used to implement most of the registries, including blocks, items, entities, biomes and dimensions. These "ordinary" registries associate entries with both namespaced textual identifiers (see #Identifier), and signed (positive) 32-bit numeric identifiers. There is also a registry of registries listing all of the registries in the registry system. Some other registries, most notably the block state registry, are however implemented in a more ad-hoc fashion.

Some registries, such as biomes and dimensions, can be customized at runtime by the server (see Registry Data), while others, such as blocks, items and entities, are hardcoded. The contents of the hardcoded registries can be extracted via the built-in Data Generators system.

Block state Each block in Minecraft has 0 or more properties, which in turn may have any number of possible values. These represent, for example, the orientations of blocks, poweredness states of redstone components, and so on. Each of the possible permutations of property values for a block is a distinct block state. The block state registry assigns a numeric identifier to every block state of every block.

A current list of properties and state ID ranges is found on burger.

Alternatively, the vanilla server now includes an option to export the current block state ID mapping, by running java -DbundlerMainClass=net.minecraft.data.Main -jar minecraft_server.jar --reports. See Data Generators for more information.

Notchian The official implementation of vanilla Minecraft as developed and released by Mojang.
Sequence The action number counter for local block changes, incremented by one when clicking a block with a hand, right clicking an item, or starting or finishing digging a block. Counter handles latency to avoid applying outdated block changes to the local world. Also is used to revert ghost blocks created when placing blocks, using buckets, or breaking blocks.

Packet format

Packets cannot be larger than 221 − 1 or 2097151 bytes (the maximum that can be sent in a 3-byte VarInt). Moreover, the length field must not be longer than 3 bytes, even if the encoded value is within the limit. Unnecessarily long encodings at 3 bytes or below are still allowed. For compressed packets, this applies to the Packet Length field, i.e. the compressed length.

Without compression

Field Name Field Type Notes
Length VarInt Length of Packet ID + Data
Packet ID VarInt Corresponds to protocol_id from the server's packet report
Data Byte Array Depends on the connection state and packet ID, see the sections below

With compression

Once a Set Compression packet (with a non-negative threshold) is sent, zlib compression is enabled for all following packets. The format of a packet changes slightly to include the size of the uncompressed packet.

Present? Compressed? Field Name Field Type Notes
always No Packet Length VarInt Length of (Data Length) + length of compressed (Packet ID + Data)
if size >= threshold No Data Length VarInt Length of uncompressed (Packet ID + Data)
Yes Packet ID VarInt zlib compressed packet ID (see the sections below)
Data Byte Array zlib compressed packet data (see the sections below)
if size < threshold No Data Length VarInt 0 to indicate uncompressed
Packet ID VarInt packet ID (see the sections below)
Data Byte Array packet data (see the sections below)

For serverbound packets, the uncompressed length of (Packet ID + Data) must not be greater than 223 or 8388608 bytes. Not that a length equal to 223 is permitted, which differs from the compressed length limit. The Notchian client, on the other hand, has no limit for the uncompressed length of incoming compressed packets.

If the size of the buffer containing the packet data and ID (as a VarInt) is smaller than the threshold specified in the packet Set Compression. It will be sent as uncompressed. This is done by setting the data length as 0. (Comparable to sending a non-compressed format with an extra 0 between the length, and packet data).

If it's larger than or equal to the threshold, then it follows the regular compressed protocol format.

The Notchian server (but not client) rejects compressed packets smaller than the threshold. Uncompressed packets exceeding the threshold, however, are accepted.

Compression can be disabled by sending the packet Set Compression with a negative Threshold, or not sending the Set Compression packet at all.

Handshaking

Clientbound

There are no clientbound packets in the Handshaking state, since the protocol immediately switches to a different state after the client sends the first packet.

Serverbound

Handshake

This causes the server to switch into the target state.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x00

resource:
intention
Handshaking Server Protocol Version VarInt See protocol version numbers (currently 767 in Minecraft 1.21).
Server Address String (255) Hostname or IP, e.g. localhost or 127.0.0.1, that was used to connect. The Notchian server does not use this information. Note that SRV records are a simple redirect, e.g. if _minecraft._tcp.example.com points to mc.example.org, users connecting to example.com will provide example.org as server address in addition to connecting to it.
Server Port Unsigned Short Default is 25565. The Notchian server does not use this information.
Next State VarInt Enum 1 for Status, 2 for Login, 3 for Transfer.

Legacy Server List Ping

Warning.png This packet uses a nonstandard format. It is never length-prefixed, and the packet ID is an Unsigned Byte instead of a VarInt.

While not technically part of the current protocol, legacy clients may send this packet to initiate Server List Ping, and modern servers should handle it correctly. The format of this packet is a remnant of the pre-Netty age, before the switch to Netty in 1.7 brought the standard format that is recognized now. This packet merely exists to inform legacy clients that they can't join our modern server.

Packet ID State Bound To Field Name Field Type Notes
0xFE Handshaking Server Payload Unsigned Byte always 1 (0x01).

See Server List Ping#1.6 for the details of the protocol that follows this packet.

Status

Main article: Server List Ping

Clientbound

Status Response

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x00

resource:
status_response
Status Client JSON Response String (32767) See Server List Ping#Status Response; as with all strings this is prefixed by its length as a VarInt.

Pong Response (status)

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x01

resource:
pong_response
Status Client Payload Long Should be the same as sent by the client.

Serverbound

Status Request

The status can only be requested once immediately after the handshake, before any ping. The server won't respond otherwise.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x00

resource:
status_request
Status Server no fields

Ping Request (status)

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x01

resource:
ping_request
Status Server Payload Long May be any number. Notchian clients use a system-dependent time value which is counted in milliseconds.

Login

The login process is as follows:

  1. C→S: Handshake with Next State set to 2 (login)
  2. C→S: Login Start
  3. S→C: Encryption Request
  4. Client auth (if enabled)
  5. C→S: Encryption Response
  6. Server auth (if enabled)
  7. Both enable encryption
  8. S→C: Set Compression (optional)
  9. S→C: Login Success
  10. C→S: Login Acknowledged

Set Compression, if present, must be sent before Login Success. Note that anything sent after Set Compression must use the Post Compression packet format.

Three modes of operation are possible depending on how the packets are sent:

  • Online-mode with encryption
  • Offline-mode with encryption
  • Offline-mode without encryption

For online-mode servers (the ones with authentication enabled), encryption is always mandatory, and the entire process described above needs to be followed.

For offline-mode servers (the ones with authentication disabled), encryption is optional, and part of the process can be skipped. In that case Login Start is directly followed by Login Success. The Notchian server only uses UUID v3 for offline player UUIDs, deriving it from the string OfflinePlayer:<player's name> For example, Notch’s offline UUID would be chosen from the string OfflinePlayer:Notch. This is not a requirement however, the UUID can be set to anything.

As of 1.21, the Notchian server never uses encryption in offline mode.

See Protocol Encryption for details.

Clientbound

Disconnect (login)

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x00

resource:
login_disconnect
Login Client Reason JSON Text Component The reason why the player was disconnected.

Encryption Request

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x01

resource:
hello
Login Client Server ID String (20) Appears to be empty.
Public Key Length VarInt Length of Public Key.
Public Key Byte Array The server's public key, in bytes.
Verify Token Length VarInt Length of Verify Token. Always 4 for Notchian servers.
Verify Token Byte Array A sequence of random bytes generated by the server.
Should authenticate Boolean Whether the client should attempt to authenticate through mojang servers.

See Protocol Encryption for details.

Login Success

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x02

resource:
game_profile
Login Client UUID UUID
Username String (16)
Number Of Properties VarInt Number of elements in the following array.
Property Name Array String (32767)
Value String (32767)
Is Signed Boolean
Signature Optional String (32767) Only if Is Signed is true.
Strict Error Handling Boolean Whether the client should immediately disconnect upon a packet processing error. The Notchian client silently ignores them when this flag is false.

Warning.png This field was temporarily added in 1.20.5 as a way to aid modded servers with the transition to the new data pack & registry system, allowing them to tell the client to silently ignore packets containing inconsistent data. It will be removed in 1.21.2, but it is still present as of version 1.21.1.

The Property field looks like response of Mojang API#UUID to Profile and Skin/Cape, except using the protocol format instead of JSON. That is, each player will usually have one property with Name being “textures” and Value being a base64-encoded JSON string, as documented at Mojang API#UUID to Profile and Skin/Cape. An empty properties array is also acceptable, and will cause clients to display the player with one of the two default skins depending their UUID (again, see the Mojang API page).

Set Compression

Enables compression. If compression is enabled, all following packets are encoded in the compressed packet format. Negative values will disable compression, meaning the packet format should remain in the uncompressed packet format. However, this packet is entirely optional, and if not sent, compression will also not be enabled (the notchian server does not send the packet when compression is disabled).

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x03

resource:
login_compression
Login Client Threshold VarInt Maximum size of a packet before it is compressed.

Login Plugin Request

Used to implement a custom handshaking flow together with Login Plugin Response.

Unlike plugin messages in "play" mode, these messages follow a lock-step request/response scheme, where the client is expected to respond to a request indicating whether it understood. The notchian client always responds that it hasn't understood, and sends an empty payload.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x04

resource:
custom_query
Login Client Message ID VarInt Generated by the server - should be unique to the connection.
Channel Identifier Name of the plugin channel used to send the data.
Data Byte Array (1048576) Any data, depending on the channel. The length of this array must be inferred from the packet length.

In Notchian client, the maximum data length is 1048576 bytes.

Cookie Request (login)

Requests a cookie that was previously stored.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x05

resource:
cookie_request
Login Client Key Identifier The identifier of the cookie.

Serverbound

Login Start

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x00

resource:
hello
Login Server Name String (16) Player's Username.
Player UUID UUID The UUID of the player logging in. Unused by the Notchian server.

Encryption Response

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x01

resource:
key
Login Server Shared Secret Length VarInt Length of Shared Secret.
Shared Secret Byte Array Shared Secret value, encrypted with the server's public key.
Verify Token Length VarInt Length of Verify Token.
Verify Token Byte Array Verify Token value, encrypted with the same public key as the shared secret.

See Protocol Encryption for details.

Login Plugin Response

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x02

resource:
custom_query_answer
Login Server Message ID VarInt Should match ID from server.
Successful Boolean true if the client understood the request, false otherwise. When false, no payload follows.
Data Optional Byte Array (1048576) Any data, depending on the channel. The length of this array must be inferred from the packet length.

In Notchian server, the maximum data length is 1048576 bytes.

Login Acknowledged

Acknowledgement to the Login Success packet sent by the server.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x03

resource:
login_acknowledged
Login Server no fields

This packet switches the connection state to configuration.

Cookie Response (login)

Response to a Cookie Request (login) from the server. The Notchian server only accepts responses of up to 5 kiB in size.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x04

resource:
cookie_response
Login Server Key Identifier The identifier of the cookie.
Has Payload Boolean The payload is only present if the cookie exists on the client.
Payload Length Optional VarInt Length of the following byte array.
Payload Optional Byte Array (5120) The data of the cookie, if any.

Configuration

Clientbound

Cookie Request (configuration)

Requests a cookie that was previously stored.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x00

resource:
cookie_request
Configuration Client Key Identifier The identifier of the cookie.

Clientbound Plugin Message (configuration)

Main article: Plugin channels

Mods and plugins can use this to send their data. Minecraft itself uses several plugin channels. These internal channels are in the minecraft namespace.

More information on how it works on Dinnerbone's blog. More documentation about internal and popular registered channels are here.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x01

resource:
custom_payload
Configuration Client Channel Identifier Name of the plugin channel used to send the data.
Data Byte Array (1048576) Any data. The length of this array must be inferred from the packet length.

In Notchian client, the maximum data length is 1048576 bytes.

Disconnect (configuration)

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x02

resource:
disconnect
Configuration Client Reason Text Component The reason why the player was disconnected.

Finish Configuration

Sent by the server to notify the client that the configuration process has finished. The client answers with Acknowledge Finish Configuration whenever it is ready to continue.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x03

resource:
finish_configuration
Configuration Client no fields

This packet switches the connection state to play.

Clientbound Keep Alive (configuration)

The server will frequently send out a keep-alive, each containing a random ID. The client must respond with the same payload (see Serverbound Keep Alive). If the client does not respond to a Keep Alive packet within 15 seconds after it was sent, the server kicks the client. Vice versa, if the server does not send any keep-alives for 20 seconds, the client will disconnect and yields a "Timed out" exception.

The Notchian server uses a system-dependent time in milliseconds to generate the keep alive ID value.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x04

resource:
keep_alive
Configuration Client Keep Alive ID Long

Ping (configuration)

Packet is not used by the Notchian server. When sent to the client, client responds with a Pong packet with the same id.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x05

resource:
ping
Configuration Client ID Int

Reset Chat

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x06

resource:
reset_chat
Configuration Client no fields

Registry Data

Represents certain registries that are sent from the server and are applied on the client.

See Registry Data for details.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x07

resource:
registry_data
Configuration Client
Registry ID Identifier
Entry Count VarInt Number of entries in the following array.
Entries Entry ID Array Identifier
Has Data Boolean Whether the entry has any data following.
Data NBT Entry data. Only present if Has Data is true.

Remove Resource Pack (configuration)

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x08

resource:
resource_pack_pop
Configuration Client Has UUID Boolean Whether a specific resource pack should be removed, or all of them.
UUID Optional UUID The UUID of the resource pack to be removed. Only present if the previous field is true.

Add Resource Pack (configuration)

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x09

resource:
resource_pack_push
Configuration Client UUID UUID The unique identifier of the resource pack.
URL String (32767) The URL to the resource pack.
Hash String (40) A 40 character hexadecimal, case-insensitive SHA-1 hash of the resource pack file.
If it's not a 40 character hexadecimal string, the client will not use it for hash verification and likely waste bandwidth.
Forced Boolean The Notchian client will be forced to use the resource pack from the server. If they decline they will be kicked from the server.
Has Prompt Message Boolean Whether a custom message should be used on the resource pack prompt.
Prompt Message Optional Text Component This is shown in the prompt making the client accept or decline the resource pack. Only present if the previous field is true.

Store Cookie (configuration)

Stores some arbitrary data on the client, which persists between server transfers. The Notchian client only accepts cookies of up to 5 kiB in size.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x0A

resource:
store_cookie
Configuration Client Key Identifier The identifier of the cookie.
Payload Length VarInt Length of the following byte array.
Payload Byte Array (5120) The data of the cookie.

Transfer (configuration)

Notifies the client that it should transfer to the given server. Cookies previously stored are preserved between server transfers.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x0B

resource:
transfer
Configuration Client Host String The hostname or IP of the server.
Port VarInt The port of the server.

Feature Flags

Used to enable and disable features, generally experimental ones, on the client.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x0C

resource:
update_enabled_features
Configuration Client Total Features VarInt Number of features that appear in the array below.
Feature Flags Array of Identifier

As of 1.21, the following feature flags are available:

  • minecraft:vanilla - enables vanilla features
  • minecraft:bundle - enables support for the bundle
  • minecraft:trade_rebalance - enables support for the rebalanced villager trades

Update Tags (configuration)

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x0D

resource:
update_tags
Configuration Client Length of the array VarInt
Array of tags Registry Array Identifier Registry identifier (Vanilla expects tags for the registries minecraft:block, minecraft:item, minecraft:fluid, minecraft:entity_type, and minecraft:game_event)
Array of Tag (See below)

Tag arrays look like:

Field Name Field Type Notes
Length VarInt Number of elements in the following array
Tags Tag name Array Identifier
Count VarInt Number of elements in the following array
Entries Array of VarInt Numeric IDs of the given type (block, item, etc.). This list replaces the previous list of IDs for the given tag. If some preexisting tags are left unmentioned, a warning is printed.

See Tag on the Minecraft Wiki for more information, including a list of vanilla tags.

Clientbound Known Packs

Informs the client of which data packs are present on the server. The client is expected to respond with its own Serverbound Known Packs packet. The Notchian server does not continue with Configuration until it receives a response.

The Notchian client requires the minecraft:core pack with version 1.21 for a normal login sequence. This packet must be sent before the Registry Data packets.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x0E

resource:
select_known_packs
Configuration Client Known Pack Count VarInt The number of known packs in the following array.
Known Packs Namespace Array String
ID String
Version String

Custom Report Details (configuration)

Contains a list of key-value text entries that are included in any crash or disconnection report generated during connection to the server.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x0F

resource:
custom_report_details
Configuration Client Details Count VarInt (32) The number of details in the following array.
Details Title Array String (128)
Description String (4096)

Server Links (configuration)

This packet contains a list of links that the Notchian client will display in the menu available from the pause menu. Link labels can be built-in or custom (i.e., any text).

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x10

resource:
server_links
Configuration Client Links Count VarInt The number of links in the following array.
Links Is built-in Array Boolean True if Label is an enum (built-in label), false if it's a text component (custom label).
Label VarInt Enum / Text Component See below.
URL String Valid URL.


ID Name Notes
0 Bug Report Displayed on connection error screen; included as a comment in the disconnection report.
1 Community Guidelines
2 Support
3 Status
4 Feedback
5 Community
6 Website
7 Forums
8 News
9 Announcements

Serverbound

Client Information (configuration)

Sent when the player connects, or when settings are changed.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x00

resource:
client_information
Configuration Server Locale String (16) e.g. en_GB.
View Distance Byte Client-side render distance, in chunks.
Chat Mode VarInt Enum 0: enabled, 1: commands only, 2: hidden. See Chat#Client chat mode for more information.
Chat Colors Boolean “Colors” multiplayer setting. Can the chat be colored?
Displayed Skin Parts Unsigned Byte Bit mask, see below.
Main Hand VarInt Enum 0: Left, 1: Right.
Enable text filtering Boolean Enables filtering of text on signs and written book titles. Currently always false (i.e. the filtering is disabled)
Allow server listings Boolean Servers usually list online players, this option should let you not show up in that list.

Displayed Skin Parts flags:

  • Bit 0 (0x01): Cape enabled
  • Bit 1 (0x02): Jacket enabled
  • Bit 2 (0x04): Left Sleeve enabled
  • Bit 3 (0x08): Right Sleeve enabled
  • Bit 4 (0x10): Left Pants Leg enabled
  • Bit 5 (0x20): Right Pants Leg enabled
  • Bit 6 (0x40): Hat enabled

The most significant bit (bit 7, 0x80) appears to be unused.

Cookie Response (configuration)

Response to a Cookie Request (configuration) from the server. The Notchian server only accepts responses of up to 5 kiB in size.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x01

resource:
cookie_response
Configuration Server Key Identifier The identifier of the cookie.
Has Payload Boolean The payload is only present if the cookie exists on the client.
Payload Length Optional VarInt Length of the following byte array.
Payload Optional Byte Array (5120) The data of the cookie, if any.

Serverbound Plugin Message (configuration)

Main article: Plugin channels

Mods and plugins can use this to send their data. Minecraft itself uses some plugin channels. These internal channels are in the minecraft namespace.

More documentation on this: https://dinnerbone.com/blog/2012/01/13/minecraft-plugin-channels-messaging/

Note that the length of Data is known only from the packet length, since the packet has no length field of any kind.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x02

resource:
custom_payload
Configuration Server Channel Identifier Name of the plugin channel used to send the data.
Data Byte Array (32767) Any data, depending on the channel. minecraft: channels are documented here. The length of this array must be inferred from the packet length.

In Notchian server, the maximum data length is 32767 bytes.

Acknowledge Finish Configuration

Sent by the client to notify the server that the configuration process has finished. It is sent in response to the server's Finish Configuration.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x03

resource:
finish_configuration
Configuration Server no fields

This packet switches the connection state to play.

Serverbound Keep Alive (configuration)

The server will frequently send out a keep-alive (see Clientbound Keep Alive), each containing a random ID. The client must respond with the same packet.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x04

resource:
keep_alive
Configuration Server Keep Alive ID Long

Pong (configuration)

Response to the clientbound packet (Ping) with the same id.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x05

resource:
pong
Configuration Server ID Int id is the same as the ping packet

Resource Pack Response (configuration)

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x06

resource:
resource_pack
Configuration Server
UUID UUID The unique identifier of the resource pack received in the Add Resource Pack (configuration) request.
Result VarInt Enum Result ID (see below).

Result can be one of the following values:

ID Result
0 Successfully downloaded
1 Declined
2 Failed to download
3 Accepted
4 Downloaded
5 Invalid URL
6 Failed to reload
7 Discarded

Serverbound Known Packs

Informs the server of which data packs are present on the client. The client sends this in response to Clientbound Known Packs.

If the client specifies a pack in this packet, the server should omit its contained data from the Registry Data packet.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x07

resource:
select_known_packs
Configuration Server Known Pack Count VarInt The number of known packs in the following array.
Known Packs Namespace Array String
ID String
Version String

Play

Clientbound

Bundle Delimiter

The delimiter for a bundle of packets. When received, the client should store every subsequent packet it receives, and wait until another delimiter is received. Once that happens, the client is guaranteed to process every packet in the bundle on the same tick, and the client should stop storing packets.

As of 1.20.6, the Notchian server only uses this to ensure Spawn Entity and associated packets used to configure the entity happen on the same tick. Each entity gets a separate bundle.

The Notchian client doesn't allow more than 4096 packets in the same bundle.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x00

resource:
bundle_delimiter
Play Client no fields

Spawn Entity

Sent by the server when an entity (aside from Experience Orb) is created.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x01

resource:
add_entity
Play Client Entity ID VarInt A unique integer ID mostly used in the protocol to identify the entity.
Entity UUID UUID A unique identifier that is mostly used in persistence and places where the uniqueness matters more.
Type VarInt ID in the minecraft:entity_type registry (see "type" field in Entity metadata#Entities).
X Double
Y Double
Z Double
Pitch Angle To get the real pitch, you must divide this by (256.0F / 360.0F)
Yaw Angle To get the real yaw, you must divide this by (256.0F / 360.0F)
Head Yaw Angle Only used by living entities, where the head of the entity may differ from the general body rotation.
Data VarInt Meaning dependent on the value of the Type field, see Object Data for details.
Velocity X Short Same units as Set Entity Velocity.
Velocity Y Short
Velocity Z Short

Warning.png The points listed below should be considered when this packet is used to spawn a player entity.

When in online mode, the UUIDs must be valid and have valid skin blobs. In offline mode, the Notchian server uses UUID v3 and chooses the player's UUID by using the String OfflinePlayer:<player name>, encoding it in UTF-8 (and case-sensitive), then processes it with UUID.nameUUIDFromBytes.

For NPCs UUID v2 should be used. Note:

<+Grum> i will never confirm this as a feature you know that :)

In an example UUID, xxxxxxxx-xxxx-Yxxx-xxxx-xxxxxxxxxxxx, the UUID version is specified by Y. So, for UUID v3, Y will always be 3, and for UUID v2, Y will always be 2.

Spawn Experience Orb

Spawns one or more experience orbs.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x02

resource:
add_experience_orb
Play Client Entity ID VarInt
X Double
Y Double
Z Double
Count Short The amount of experience this orb will reward once collected.

Entity Animation

Sent whenever an entity should change animation.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x03

resource:
animate
Play Client Entity ID VarInt Player ID.
Animation Unsigned Byte Animation ID (see below).

Animation can be one of the following values:

ID Animation
0 Swing main arm
2 Leave bed
3 Swing offhand
4 Critical effect
5 Magic critical effect

Award Statistics

Sent as a response to Client Status (id 1). Will only send the changed values if previously requested.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x04

resource:
award_stats
Play Client Count VarInt Number of elements in the following array.
Statistic Category ID Array VarInt See below.
Statistic ID VarInt See below.
Value VarInt The amount to set it to.

Categories (these are namespaced, but with : replaced with .):

Name ID Registry
minecraft.mined 0 Blocks
minecraft.crafted 1 Items
minecraft.used 2 Items
minecraft.broken 3 Items
minecraft.picked_up 4 Items
minecraft.dropped 5 Items
minecraft.killed 6 Entities
minecraft.killed_by 7 Entities
minecraft.custom 8 Custom

Blocks, Items, and Entities use block (not block state), item, and entity ids.

Custom has the following (unit only matters for clients):

Name ID Unit
minecraft.leave_game 0 None
minecraft.play_one_minute 1 Time
minecraft.time_since_death 2 Time
minecraft.time_since_rest 3 Time
minecraft.sneak_time 4 Time
minecraft.walk_one_cm 5 Distance
minecraft.crouch_one_cm 6 Distance
minecraft.sprint_one_cm 7 Distance
minecraft.walk_on_water_one_cm 8 Distance
minecraft.fall_one_cm 9 Distance
minecraft.climb_one_cm 10 Distance
minecraft.fly_one_cm 11 Distance
minecraft.walk_under_water_one_cm 12 Distance
minecraft.minecart_one_cm 13 Distance
minecraft.boat_one_cm 14 Distance
minecraft.pig_one_cm 15 Distance
minecraft.horse_one_cm 16 Distance
minecraft.aviate_one_cm 17 Distance
minecraft.swim_one_cm 18 Distance
minecraft.strider_one_cm 19 Distance
minecraft.jump 20 None
minecraft.drop 21 None
minecraft.damage_dealt 22 Damage
minecraft.damage_dealt_absorbed 23 Damage
minecraft.damage_dealt_resisted 24 Damage
minecraft.damage_taken 25 Damage
minecraft.damage_blocked_by_shield 26 Damage
minecraft.damage_absorbed 27 Damage
minecraft.damage_resisted 28 Damage
minecraft.deaths 29 None
minecraft.mob_kills 30 None
minecraft.animals_bred 31 None
minecraft.player_kills 32 None
minecraft.fish_caught 33 None
minecraft.talked_to_villager 34 None
minecraft.traded_with_villager 35 None
minecraft.eat_cake_slice 36 None
minecraft.fill_cauldron 37 None
minecraft.use_cauldron 38 None
minecraft.clean_armor 39 None
minecraft.clean_banner 40 None
minecraft.clean_shulker_box 41 None
minecraft.interact_with_brewingstand 42 None
minecraft.interact_with_beacon 43 None
minecraft.inspect_dropper 44 None
minecraft.inspect_hopper 45 None
minecraft.inspect_dispenser 46 None
minecraft.play_noteblock 47 None
minecraft.tune_noteblock 48 None
minecraft.pot_flower 49 None
minecraft.trigger_trapped_chest 50 None
minecraft.open_enderchest 51 None
minecraft.enchant_item 52 None
minecraft.play_record 53 None
minecraft.interact_with_furnace 54 None
minecraft.interact_with_crafting_table 55 None
minecraft.open_chest 56 None
minecraft.sleep_in_bed 57 None
minecraft.open_shulker_box 58 None
minecraft.open_barrel 59 None
minecraft.interact_with_blast_furnace 60 None
minecraft.interact_with_smoker 61 None
minecraft.interact_with_lectern 62 None
minecraft.interact_with_campfire 63 None
minecraft.interact_with_cartography_table 64 None
minecraft.interact_with_loom 65 None
minecraft.interact_with_stonecutter 66 None
minecraft.bell_ring 67 None
minecraft.raid_trigger 68 None
minecraft.raid_win 69 None
minecraft.interact_with_anvil 70 None
minecraft.interact_with_grindstone 71 None
minecraft.target_hit 72 None
minecraft.interact_with_smithing_table 73 None

Units:

  • None: just a normal number (formatted with 0 decimal places)
  • Damage: value is 10 times the normal amount
  • Distance: a distance in centimeters (hundredths of blocks)
  • Time: a time span in ticks

Acknowledge Block Change

Acknowledges a user-initiated block change. After receiving this packet, the client will display the block state sent by the server instead of the one predicted by the client.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x05

resource:
block_change_ack
Play Client Sequence ID VarInt Represents the sequence to acknowledge, this is used for properly syncing block changes to the client after interactions.

Set Block Destroy Stage

0–9 are the displayable destroy stages and each other number means that there is no animation on this coordinate.

Block break animations can still be applied on air; the animation will remain visible although there is no block being broken. However, if this is applied to a transparent block, odd graphical effects may happen, including water losing its transparency. (An effect similar to this can be seen in normal gameplay when breaking ice blocks)

If you need to display several break animations at the same time you have to give each of them a unique Entity ID. The entity ID does not need to correspond to an actual entity on the client. It is valid to use a randomly generated number.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x06

resource:
block_destruction
Play Client Entity ID VarInt The ID of the entity breaking the block.
Location Position Block Position.
Destroy Stage Byte 0–9 to set it, any other value to remove it.

Block Entity Data

Sets the block entity associated with the block at the given location.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x07

resource:
block_entity_data
Play Client Location Position
Type VarInt The type of the block entity
NBT Data NBT Data to set. May be a TAG_END (0), in which case the block entity at the given location is removed (though this is not required since the client will remove the block entity automatically on chunk unload or block removal).

Block Action

This packet is used for a number of actions and animations performed by blocks, usually non-persistent. The client ignores the provided block type and instead uses the block state in their world.

See Block Actions for a list of values.

Warning.png This packet uses a block ID from the minecraft:block registry, not a block state.

Packet ID State Bound To Field Name Field Type Notes
0x08 Play Client Location Position Block coordinates.
Action ID (Byte 1) Unsigned Byte Varies depending on block — see Block Actions.
Action Parameter (Byte 2) Unsigned Byte Varies depending on block — see Block Actions.
Block Type VarInt The block type ID for the block. This value is unused by the Notchian client, as it will infer the type of block based on the given position.

Block Update

Fired whenever a block is changed within the render distance.

Warning.png Changing a block in a chunk that is not loaded is not a stable action. The Notchian client currently uses a shared empty chunk which is modified for all block changes in unloaded chunks; while in 1.9 this chunk never renders in older versions the changed block will appear in all copies of the empty chunk. Servers should avoid sending block changes in unloaded chunks and clients should ignore such packets.

Packet ID State Bound To Field Name Field Type Notes
0x09 Play Client Location Position Block Coordinates.
Block ID VarInt The new block state ID for the block as given in the block state registry.

Boss Bar

Packet ID State Bound To Field Name Field Type Notes
0x0A Play Client UUID UUID Unique ID for this bar.
Action VarInt Enum Determines the layout of the remaining packet.
Action Field Name
0: add Title Text Component
Health Float From 0 to 1. Values greater than 1 do not crash a Notchian client, and start rendering part of a second health bar at around 1.5.
Color VarInt Enum Color ID (see below).
Division VarInt Enum Type of division (see below).
Flags Unsigned Byte Bit mask. 0x01: should darken sky, 0x02: is dragon bar (used to play end music), 0x04: create fog (previously was also controlled by 0x02).
1: remove no fields no fields Removes this boss bar.
2: update health Health Float as above
3: update title Title Text Component
4: update style Color VarInt Enum Color ID (see below).
Dividers VarInt Enum as above
5: update flags Flags Unsigned Byte as above
ID Color
0 Pink
1 Blue
2 Red
3 Green
4 Yellow
5 Purple
6 White
ID Type of division
0 No division
1 6 notches
2 10 notches
3 12 notches
4 20 notches

Change Difficulty

Changes the difficulty setting in the client's option menu

Packet ID State Bound To Field Name Field Type Notes
0x0B Play Client Difficulty Unsigned Byte 0: peaceful, 1: easy, 2: normal, 3: hard.
Difficulty locked? Boolean

Chunk Batch Finished

Marks the end of a chunk batch. The Notchian client marks the time it receives this packet and calculates the elapsed duration since the beginning of the chunk batch. The server uses this duration and the batch size received in this packet to estimate the number of milliseconds elapsed per chunk received. This value is then used to calculate the desired number of chunks per tick through the formula 25 / millisPerChunk, which is reported to the server through Chunk Batch Received. This likely uses 25 instead of the normal tick duration of 50 so chunk processing will only use half of the client's and network's bandwidth.

The Notchian client uses the samples from the latest 15 batches to estimate the milliseconds per chunk number.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x0C

resource:
chunk_batch_finished
Play Client Batch size VarInt Number of chunks.

Chunk Batch Start

Marks the start of a chunk batch. The Notchian client marks and stores the time it receives this packet.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x0D

resource:
chunk_batch_start
Play Client no fields

Chunk Biomes

Packet ID State Bound To Field Name Field Type Notes
0x0E Play Client
Number of chunks VarInt Number of elements in the following array
Chunk biome data Chunk Z Array Int Chunk coordinate (block coordinate divided by 16, rounded down)
Chunk X Int Chunk coordinate (block coordinate divided by 16, rounded down)
Size VarInt Size of Data in bytes
Data Byte Array Chunk data structure, with sections containing only the Biomes field

Note: The order of X and Z is inverted, because the client reads them as one big-endian Long, with Z being the upper 32 bits.

Clear Titles

Clear the client's current title information, with the option to also reset it.

Packet ID State Bound To Field Name Field Type Notes
0x0F Play Client Reset Boolean

Command Suggestions Response

The server responds with a list of auto-completions of the last word sent to it. In the case of regular chat, this is a player username. Command names and parameters are also supported. The client sorts these alphabetically before listing them.

Packet ID State Bound To Field Name Field Type Notes
0x10 Play Client
ID VarInt Transaction ID.
Start VarInt Start of the text to replace.
Length VarInt Length of the text to replace.
Count VarInt Number of elements in the following array.
Matches Match Array String (32767) One eligible value to insert, note that each command is sent separately instead of in a single string, hence the need for Count. Note that for instance this doesn't include a leading / on commands.
Has tooltip Boolean True if the following is present.
Tooltip Optional Text Component Tooltip to display; only present if previous boolean is true.

Commands

Lists all of the commands on the server, and how they are parsed.

This is a directed graph, with one root node. Each redirect or child node must refer only to nodes that have already been declared.

Packet ID State Bound To Field Name Field Type Notes
0x11 Play Client Count VarInt Number of elements in the following array.
Nodes Array of Node An array of nodes.
Root index VarInt Index of the root node in the previous array.

For more information on this packet, see the Command Data article.

Close Container

This packet is sent from the server to the client when a window is forcibly closed, such as when a chest is destroyed while it's open. The notchian client disregards the provided window ID and closes any active window.

Packet ID State Bound To Field Name Field Type Notes
0x12 Play Client Window ID Unsigned Byte This is the ID of the window that was closed. 0 for inventory.

Set Container Content

The inventory slots

Replaces the contents of a container window. Sent by the server upon initialization of a container window or the player's inventory, and in response to state ID mismatches (see #Click Container).

Packet ID State Bound To Field Name Field Type Notes
0x13 Play Client Window ID Unsigned Byte The ID of window which items are being sent for. 0 for player inventory. The client ignores any packets targeting a Window ID other than the current one. However, an exception is made for the player inventory, which may be targeted at any time. (The Notchian server does not appear to utilize this special case.)
State ID VarInt A server-managed sequence number used to avoid desynchronization; see #Click Container.
Count VarInt Number of elements in the following array.
Slot Data Array of Slot
Carried Item Slot Item being dragged with the mouse.

See inventory windows for further information about how slots are indexed. Use Open Screen to open the container on the client.

Set Container Property

This packet is used to inform the client that part of a GUI window should be updated.

Packet ID State Bound To Field Name Field Type Notes
0x14 Play Client Window ID Unsigned Byte
Property Short The property to be updated, see below.
Value Short The new value for the property, see below.

The meaning of the Property field depends on the type of the window. The following table shows the known combinations of window type and property, and how the value is to be interpreted.

Window type Property Value
Furnace 0: Fire icon (fuel left) counting from fuel burn time down to 0 (in-game ticks)
1: Maximum fuel burn time fuel burn time or 0 (in-game ticks)
2: Progress arrow counting from 0 to maximum progress (in-game ticks)
3: Maximum progress always 200 on the notchian server
Enchantment Table 0: Level requirement for top enchantment slot The enchantment's xp level requirement
1: Level requirement for middle enchantment slot
2: Level requirement for bottom enchantment slot
3: The enchantment seed Used for drawing the enchantment names (in SGA) clientside. The same seed is used to calculate enchantments, but some of the data isn't sent to the client to prevent easily guessing the entire list (the seed value here is the regular seed bitwise and 0xFFFFFFF0).
4: Enchantment ID shown on mouse hover over top enchantment slot The enchantment id (set to -1 to hide it), see below for values
5: Enchantment ID shown on mouse hover over middle enchantment slot
6: Enchantment ID shown on mouse hover over bottom enchantment slot
7: Enchantment level shown on mouse hover over the top slot The enchantment level (1 = I, 2 = II, 6 = VI, etc.), or -1 if no enchant
8: Enchantment level shown on mouse hover over the middle slot
9: Enchantment level shown on mouse hover over the bottom slot
Beacon 0: Power level 0-4, controls what effect buttons are enabled
1: First potion effect Potion effect ID for the first effect, or -1 if no effect
2: Second potion effect Potion effect ID for the second effect, or -1 if no effect
Anvil 0: Repair cost The repair's cost in xp levels
Brewing Stand 0: Brew time 0 – 400, with 400 making the arrow empty, and 0 making the arrow full
1: Fuel time 0 - 20, with 0 making the arrow empty, and 20 making the arrow full
Stonecutter 0: Selected recipe The index of the selected recipe. -1 means none is selected.
Loom 0: Selected pattern The index of the selected pattern. 0 means none is selected, 0 is also the internal id of the "base" pattern.
Lectern 0: Page number The current page number, starting from 0.

For an enchanting table, the following numerical IDs are used:

Numerical ID Enchantment ID Enchantment Name
0 minecraft:protection Protection
1 minecraft:fire_protection Fire Protection
2 minecraft:feather_falling Feather Falling
3 minecraft:blast_protection Blast Protection
4 minecraft:projectile_protection Projectile Protection
5 minecraft:respiration Respiration
6 minecraft:aqua_affinity Aqua Affinity
7 minecraft:thorns Thorns
8 minecraft:depth_strider Depth Strider
9 minecraft:frost_walker Frost Walker
10 minecraft:binding_curse Curse of Binding
11 minecraft:soul_speed Soul Speed
12 minecraft:swift_sneak Swift Sneak
13 minecraft:sharpness Sharpness
14 minecraft:smite Smite
15 minecraft:bane_of_arthropods Bane of Arthropods
16 minecraft:knockback Knockback
17 minecraft:fire_aspect Fire Aspect
18 minecraft:looting Looting
19 minecraft:sweeping_edge Sweeping Edge
20 minecraft:efficiency Efficiency
21 minecraft:silk_touch Silk Touch
22 minecraft:unbreaking Unbreaking
23 minecraft:fortune Fortune
24 minecraft:power Power
25 minecraft:punch Punch
26 minecraft:flame Flame
27 minecraft:infinity Infinity
28 minecraft:luck_of_the_sea Luck of the Sea
29 minecraft:lure Lure
30 minecraft:loyalty Loyalty
31 minecraft:impaling Impaling
32 minecraft:riptide Riptide
33 minecraft:channeling Channeling
34 minecraft:multishot Multishot
35 minecraft:quick_charge Quick Charge
36 minecraft:piercing Piercing
37 minecraft:density Density
38 minecraft:breach Breach
39 minecraft:wind_burst Wind Burst
40 minecraft:mending Mending
41 minecraft:vanishing_curse Curse of Vanishing

Set Container Slot

Sent by the server when an item in a slot (in a window) is added/removed.

Packet ID State Bound To Field Name Field Type Notes
0x15 Play Client Window ID Byte The window which is being updated. 0 for player inventory. The client ignores any packets targeting a Window ID other than the current one; see below for exceptions.
State ID VarInt A server-managed sequence number used to avoid desynchronization; see #Click Container.
Slot Short The slot that should be updated.
Slot Data Slot

If Window ID is 0, the hotbar and offhand slots (slots 36 through 45) may be updated even when a different container window is open. (The Notchian server does not appear to utilize this special case.) Updates are also restricted to those slots when the player is looking at a creative inventory tab other than the survival inventory. (The Notchian server does not handle this restriction in any way, leading to MC-242392.)

If Window ID is -1, the item being dragged with the mouse is set. In this case, State ID and Slot are ignored.

If Window ID is -2, any slot in the player's inventory can be updated irrespective of the current container window. In this case, State ID is ignored, and the Notchian server uses a bogus value of 0. Used by the Notchian server to implement the #Pick Item functionality.

When a container window is open, the server never sends updates targeting Window ID 0—all of the window types include slots for the player inventory. The client must automatically apply changes targeting the inventory portion of a container window to the main inventory; the server does not resend them for ID 0 when the window is closed. However, since the armor and offhand slots are only present on ID 0, updates to those slots occurring while a window is open must be deferred by the server until the window's closure.

Cookie Request (play)

Requests a cookie that was previously stored.

Packet ID State Bound To Field Name Field Type Notes
0x16 Play Client Key Identifier The identifier of the cookie.

Set Cooldown

Applies a cooldown period to all items with the given type. Used by the Notchian server with enderpearls. This packet should be sent when the cooldown starts and also when the cooldown ends (to compensate for lag), although the client will end the cooldown automatically. Can be applied to any item, note that interactions still get sent to the server with the item but the client does not play the animation nor attempt to predict results (i.e block placing).

Packet ID State Bound To Field Name Field Type Notes
0x17 Play Client Item ID VarInt Numeric ID of the item to apply a cooldown to.
Cooldown Ticks VarInt Number of ticks to apply a cooldown for, or 0 to clear the cooldown.

Chat Suggestions

Unused by the Notchian server. Likely provided for custom servers to send chat message completions to clients.

Packet ID State Bound To Field Name Field Type Notes
0x18 Play Client Action VarInt Enum 0: Add, 1: Remove, 2: Set
Count VarInt Number of elements in the following array.
Entries Array of String (32767)

Clientbound Plugin Message (play)

Main article: Plugin channels

Mods and plugins can use this to send their data. Minecraft itself uses several plugin channels. These internal channels are in the minecraft namespace.

More information on how it works on Dinnerbone's blog. More documentation about internal and popular registered channels are here.

Packet ID State Bound To Field Name Field Type Notes
0x19 Play Client Channel Identifier Name of the plugin channel used to send the data.
Data Byte Array (1048576) Any data. The length of this array must be inferred from the packet length.

In Notchian client, the maximum data length is 1048576 bytes.

Damage Event

Packet ID State Bound To Field Name Field Type Notes
0x1A Play Client
Entity ID VarInt The ID of the entity taking damage
Source Type ID VarInt The type of damage in the minecraft:damage_type registry, defined by the Registry Data packet.
Source Cause ID VarInt The ID + 1 of the entity responsible for the damage, if present. If not present, the value is 0
Source Direct ID VarInt The ID + 1 of the entity that directly dealt the damage, if present. If not present, the value is 0. If this field is present:
  • and damage was dealt indirectly, such as by the use of a projectile, this field will contain the ID of such projectile;
  • and damage was dealt dirctly, such as by manually attacking, this field will contain the same value as Source Cause ID.
Has Source Position Boolean Indicates the presence of the three following fields.

The Notchian server sends the Source Position when the damage was dealt by the /damage command and a position was specified

Source Position X Optional Double Only present if Has Source Position is true
Source Position Y Optional Double Only present if Has Source Position is true
Source Position Z Optional Double Only present if Has Source Position is true

Debug Sample

Sample data that is sent periodically after the client has subscribed with Debug Sample Subscription.

The Notchian server only sends debug samples to players that are server operators.

Packet ID State Bound To Field Name Field Type Notes
0x1B Play Client Sample Length VarInt The length of the following array.
Sample Long Array Array of type-dependent samples.
Sample Type VarInt Enum See below.

Types:

Id Name Description
0 Tick time Four different tick-related metrics, each one represented by one long on the array.

They are measured in nano-seconds, and are as follows:

  • 0: Full tick time: Aggregate of the three times below;
  • 1: Server tick time: Main server tick logic;
  • 2: Tasks time: Tasks scheduled to execute after the main logic;
  • 3: Idle time: Time idling to complete the full 50ms tick cycle.

Note that the Notchian client calculates the timings used for min/max/average display by subtracting the idle time from the full tick time. This can cause the displayed values to go negative if the idle time is (nonsensically) greater than the full tick time.

Delete Message

Removes a message from the client's chat. This only works for messages with signatures, system messages cannot be deleted with this packet.

Packet ID State Bound To Field Name Field Type Notes
0x1C Play Client Message ID VarInt The message Id + 1, used for validating message signature. The next field is present only when value of this field is equal to 0.
Signature Optional Byte Array (256) The previous message's signature. Always 256 bytes and not length-prefixed.

Disconnect (play)

Sent by the server before it disconnects a client. The client assumes that the server has already closed the connection by the time the packet arrives.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x1D

resource:
disconnect
Play Client Reason Text Component Displayed to the client when the connection terminates.

Disguised Chat Message

Main article: Chat

Sends the client a chat message, but without any message signing information.

The Notchian server uses this packet when the console is communicating with players through commands, such as /say, /tell, /me, among others.

Packet ID State Bound To Field Name Field Type Notes
0x1E Play Client Message Text Component This is used as the content parameter when formatting the message on the client.
Chat Type VarInt The type of chat in the minecraft:chat_type registry, defined by the Registry Data packet.
Sender Name Text Component The name of the one sending the message, usually the sender's display name.

This is used as the sender parameter when formatting the message on the client.

Has Target Name Boolean True if target name is present.
Target Name Text Component The name of the one receiving the message, usually the receiver's display name. Only present if previous boolean is true.

This is used as the target parameter when formatting the message on the client.

Entity Event

Entity statuses generally trigger an animation for an entity. The available statuses vary by the entity's type (and are available to subclasses of that type as well).

Packet ID State Bound To Field Name Field Type Notes
0x1F Play Client Entity ID Int
Entity Status Byte Enum See Entity statuses for a list of which statuses are valid for each type of entity.

Explosion

Sent when an explosion occurs (creepers, TNT, and ghast fireballs).

Each block in Records is set to air. Coordinates for each axis in record is int(X) + record.x

Packet ID State Bound To Field Name Field Type Notes
0x20 Play Client X Double
Y Double
Z Double
Strength Float If the strength is greater or equal to 2.0, or the block interaction is not 0 (keep), large explosion particles are used. Otherwise, small explosion particles are used.
Record Count VarInt Number of elements in the following array.
Records Array of (Byte, Byte, Byte) Each record is 3 signed bytes long; the 3 bytes are the XYZ (respectively) signed offsets of affected blocks.
Player Motion X Float X velocity of the player being pushed by the explosion.
Player Motion Y Float Y velocity of the player being pushed by the explosion.
Player Motion Z Float Z velocity of the player being pushed by the explosion.
Block Interaction VarInt Enum 0 = keep, 1 = destroy, 2 = destroy_with_decay, 3 = trigger_block.
Small Explosion Particle ID VarInt The particle ID listed in Particles.
Small Explosion Particle Data Varies Particle data as specified in Particles.
Large Explosion Particle ID VarInt The particle ID listed in Particles.
Large Explosion Particle Data Varies Particle data as specified in Particles.
Explosion Sound Sound Name Identifier The name of the sound played.
Has Fixed Range Optional Boolean Whether is has fixed range.
Range Optional Float The fixed range of the sound. Only present if previous boolean is true.

Unload Chunk

Tells the client to unload a chunk column.

Packet ID State Bound To Field Name Field Type Notes
0x21 Play Client Chunk Z Int Block coordinate divided by 16, rounded down.
Chunk X Int Block coordinate divided by 16, rounded down.

Note: The order is inverted, because the client reads this packet as one big-endian Long, with Z being the upper 32 bits.

It is legal to send this packet even if the given chunk is not currently loaded.

Game Event

Used for a wide variety of game events, from weather to bed use to game mode to demo messages.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x22

resource:
game_event
Play Client Event Unsigned Byte See below.
Value Float Depends on Event.

Events:

Event Effect Value
0 No respawn block available Note: Displays message 'block.minecraft.spawn.not_valid' (You have no home bed or charged respawn anchor, or it was obstructed) to the player.
1 Begin raining
2 End raining
3 Change game mode 0: Survival, 1: Creative, 2: Adventure, 3: Spectator.
4 Win game 0: Just respawn player.
1: Roll the credits and respawn player.
Note that 1 is only sent by notchian server when player has not yet achieved advancement "The end?", else 0 is sent.
5 Demo event 0: Show welcome to demo screen.
101: Tell movement controls.
102: Tell jump control.
103: Tell inventory control.
104: Tell that the demo is over and print a message about how to take a screenshot.
6 Arrow hit player Note: Sent when any player is struck by an arrow.
7 Rain level change Note: Seems to change both sky color and lighting.
Rain level ranging from 0 to 1.
8 Thunder level change Note: Seems to change both sky color and lighting (same as Rain level change, but doesn't start rain). It also requires rain to render by notchian client.
Thunder level ranging from 0 to 1.
9 Play pufferfish sting sound
10 Play elder guardian mob appearance (effect and sound)
11 Enable respawn screen 0: Enable respawn screen.
1: Immediately respawn (sent when the doImmediateRespawn gamerule changes).
12 Limited crafting 0: Disable limited crafting.
1: Enable limited crafting (sent when the doLimitedCrafting gamerule changes).
13 Start waiting for level chunks Instructs the client to begin the waiting process for the level chunks.
Sent by the server after the level is cleared on the client and is being re-sent (either during the first, or subsequent reconfigurations).

Open Horse Screen

This packet is used exclusively for opening the horse GUI. Open Screen is used for all other GUIs. The client will not open the inventory if the Entity ID does not point to an horse-like animal.

Packet ID State Bound To Field Name Field Type Notes
0x23 Play Client Window ID Unsigned Byte
Slot count VarInt
Entity ID Int

Hurt Animation

Plays a bobbing animation for the entity receiving damage.

Packet ID State Bound To Field Name Field Type Notes
0x24 Play Client
Entity ID VarInt The ID of the entity taking damage
Yaw Float The direction the damage is coming from in relation to the entity

Initialize World Border

Packet ID State Bound To Field Name Field Type Notes
0x25 Play Client X Double
Z Double
Old Diameter Double Current length of a single side of the world border, in meters.
New Diameter Double Target length of a single side of the world border, in meters.
Speed VarLong Number of real-time milliseconds until New Diameter is reached. It appears that Notchian server does not sync world border speed to game ticks, so it gets out of sync with server lag. If the world border is not moving, this is set to 0.
Portal Teleport Boundary VarInt Resulting coordinates from a portal teleport are limited to ±value. Usually 29999984.
Warning Blocks VarInt In meters.
Warning Time VarInt In seconds as set by /worldborder warning time.

The Notchian client determines how solid to display the warning by comparing to whichever is higher, the warning distance or whichever is lower, the distance from the current diameter to the target diameter or the place the border will be after warningTime seconds. In pseudocode:

distance = max(min(resizeSpeed * 1000 * warningTime, abs(targetDiameter - currentDiameter)), warningDistance);
if (playerDistance < distance) {
    warning = 1.0 - playerDistance / distance;
} else {
    warning = 0.0;
}

Clientbound Keep Alive (play)

The server will frequently send out a keep-alive, each containing a random ID. The client must respond with the same payload (see Serverbound Keep Alive). If the client does not respond to a Keep Alive packet within 15 seconds after it was sent, the server kicks the client. Vice versa, if the server does not send any keep-alives for 20 seconds, the client will disconnect and yields a "Timed out" exception.

The Notchian server uses a system-dependent time in milliseconds to generate the keep alive ID value.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x26

resource:
keep_alive
Play Client Keep Alive ID Long

Chunk Data and Update Light

Main article: Chunk Format
See also: #Unload Chunk

Sent when a chunk comes into the client's view distance, specifying its terrain, lighting and block entities.

The chunk must be within the view area previously specified with Set Center Chunk; see that packet for details.

It is not strictly necessary to send all block entities in this packet; it is still legal to send them with Block Entity Data later.

Packet ID State Bound To Field Name Field Type Notes
0x27 Play Client Chunk X Int Chunk coordinate (block coordinate divided by 16, rounded down)
Chunk Z Int Chunk coordinate (block coordinate divided by 16, rounded down)
Heightmaps NBT See Chunk Format#Heightmaps structure
Size VarInt Size of Data in bytes
Data Byte Array See Chunk Format#Data structure
Number of block entities VarInt Number of elements in the following array
Block Entity Packed XZ Array Unsigned Byte The packed section coordinates are relative to the chunk they are in. Values 0-15 are valid.
packed_xz = ((blockX & 15) << 4) | (blockZ & 15) // encode
x = packed_xz >> 4, z = packed_xz & 15 // decode
Y Short The height relative to the world
Type VarInt The type of block entity
Data NBT The block entity's data, without the X, Y, and Z values
Sky Light Mask BitSet BitSet containing bits for each section in the world + 2. Each set bit indicates that the corresponding 16×16×16 chunk section has data in the Sky Light array below. The least significant bit is for blocks 16 blocks to 1 block below the min world height (one section below the world), while the most significant bit covers blocks 1 to 16 blocks above the max world height (one section above the world).
Block Light Mask BitSet BitSet containing bits for each section in the world + 2. Each set bit indicates that the corresponding 16×16×16 chunk section has data in the Block Light array below. The order of bits is the same as in Sky Light Mask.
Empty Sky Light Mask BitSet BitSet containing bits for each section in the world + 2. Each set bit indicates that the corresponding 16×16×16 chunk section has all zeros for its Sky Light data. The order of bits is the same as in Sky Light Mask.
Empty Block Light Mask BitSet BitSet containing bits for each section in the world + 2. Each set bit indicates that the corresponding 16×16×16 chunk section has all zeros for its Block Light data. The order of bits is the same as in Sky Light Mask.
Sky Light array count VarInt Number of entries in the following array; should match the number of bits set in Sky Light Mask
Sky Light arrays Length Array VarInt Length of the following array in bytes (always 2048)
Sky Light array Byte Array (2048) There is 1 array for each bit set to true in the sky light mask, starting with the lowest value. Half a byte per light value. Indexed ((y<<8) | (z<<4) | x) / 2 If there's a remainder, masked 0xF0 else 0x0F.
Block Light array count VarInt Number of entries in the following array; should match the number of bits set in Block Light Mask
Block Light arrays Length Array VarInt Length of the following array in bytes (always 2048)
Block Light array Byte Array (2048) There is 1 array for each bit set to true in the block light mask, starting with the lowest value. Half a byte per light value. Indexed ((y<<8) | (z<<4) | x) / 2 If there's a remainder, masked 0xF0 else 0x0F.

Unlike the Update Light packet which uses the same format, setting the bit corresponding to a section to 0 in both of the block light or sky light masks does not appear to be useful, and the results in testing have been highly inconsistent.

World Event

Huh.png The following information needs to be added to this page:
The events listed below are not up-to-date with the latest release version, being either improperly documented or missing from the list altogether.

Sent when a client is to play a sound or particle effect.

By default, the Minecraft client adjusts the volume of sound effects based on distance. The final boolean field is used to disable this, and instead the effect is played from 2 blocks away in the correct direction. Currently this is only used for effect 1023 (wither spawn), effect 1028 (enderdragon death), and effect 1038 (end portal opening); it is ignored on other effects.

Packet ID State Bound To Field Name Field Type Notes
0x28 Play Client Event Int The event, see below.
Location Position The location of the event.
Data Int Extra data for certain events, see below.
Disable Relative Volume Boolean See above.

Events:

ID Name Data
Sound
1000 Dispenser dispenses
1001 Dispenser fails to dispense
1002 Dispenser shoots
1003 Ender eye launched
1004 Firework shot
1009 Fire extinguished
1010 Play record An ID in the minecraft:item registry, corresponding to a record item. If the ID doesn't correspond to a record, the packet is ignored. Any record already being played at the given location is overwritten. See Data Generators for information on item IDs.
1011 Stop record
1015 Ghast warns
1016 Ghast shoots
1017 Enderdragon shoots
1018 Blaze shoots
1019 Zombie attacks wood door
1020 Zombie attacks iron door
1021 Zombie breaks wood door
1022 Wither breaks block
1023 Wither spawned
1024 Wither shoots
1025 Bat takes off
1026 Zombie infects
1027 Zombie villager converted
1028 Ender dragon death
1029 Anvil destroyed
1030 Anvil used
1031 Anvil landed
1032 Portal travel
1033 Chorus flower grown
1034 Chorus flower died
1035 Brewing stand brewed
1038 End portal created in overworld
1039 Phantom bites
1040 Zombie converts to drowned
1041 Husk converts to zombie by drowning
1042 Grindstone used
1043 Book page turned
1044 Smithing table used
1045 Pointed dripstone landing
1046 Lava dripping on cauldron from dripstone
1047 Water dripping on cauldron from dripstone
1048 Skeleton converts to stray
1049 Crafter successfully crafts item
1050 Crafter fails to craft item
Particle
1500 Composter composts
1501 Lava converts block (either water to stone, or removes existing blocks such as torches)
1502 Redstone torch burns out
1503 Ender eye placed
1504 Fluid drips from dripstone
1505 Bonemeal particles How many particles to spawn.
2000 Spawns 10 smoke particles, e.g. from a fire Direction, see below.
2001 Block break + block break sound Block state ID (see Chunk Format#Block state registry).
2002 Splash potion. Particle effect + glass break sound. RGB color as an integer (e.g. 8364543 for #7FA1FF).
2003 Eye of Ender entity break animation — particles and sound
2004 Mob spawn particle effect: smoke + flames
2006 Dragon breath
2007 Instant splash potion. Particle effect + glass break sound. RGB color as an integer (e.g. 8364543 for #7FA1FF).
2008 Ender dragon destroys block
2009 Wet sponge vaporizes in nether
3000 End gateway spawn
3001 Enderdragon growl
3002 Electric spark
3003 Copper apply wax
3004 Copper remove wax
3005 Copper scrape oxidation

Smoke directions:

ID Direction
0 Down
1 Up
2 North
3 South
4 West
5 East

Particle

Displays the named particle

Packet ID State Bound To Field Name Field Type Notes
0x29 Play Client Long Distance Boolean If true, particle distance increases from 256 to 65536.
X Double X position of the particle.
Y Double Y position of the particle.
Z Double Z position of the particle.
Offset X Float This is added to the X position after being multiplied by random.nextGaussian().
Offset Y Float This is added to the Y position after being multiplied by random.nextGaussian().
Offset Z Float This is added to the Z position after being multiplied by random.nextGaussian().
Max Speed Float
Particle Count Int The number of particles to create.
Particle ID VarInt The particle ID listed in Particles.
Data Varies Particle data as specified in Particles.

Update Light

Updates light levels for a chunk. See Light for information on how lighting works in Minecraft.

Packet ID State Bound To Field Name Field Type Notes
0x2A Play Client Chunk X VarInt Chunk coordinate (block coordinate divided by 16, rounded down)
Chunk Z VarInt Chunk coordinate (block coordinate divided by 16, rounded down)
Sky Light Mask BitSet BitSet containing bits for each section in the world + 2. Each set bit indicates that the corresponding 16×16×16 chunk section has data in the Sky Light array below. The least significant bit is for blocks 16 blocks to 1 block below the min world height (one section below the world), while the most significant bit covers blocks 1 to 16 blocks above the max world height (one section above the world).
Block Light Mask BitSet BitSet containing bits for each section in the world + 2. Each set bit indicates that the corresponding 16×16×16 chunk section has data in the Block Light array below. The order of bits is the same as in Sky Light Mask.
Empty Sky Light Mask BitSet BitSet containing bits for each section in the world + 2. Each set bit indicates that the corresponding 16×16×16 chunk section has all zeros for its Sky Light data. The order of bits is the same as in Sky Light Mask.
Empty Block Light Mask BitSet BitSet containing bits for each section in the world + 2. Each set bit indicates that the corresponding 16×16×16 chunk section has all zeros for its Block Light data. The order of bits is the same as in Sky Light Mask.
Sky Light array count VarInt Number of entries in the following array; should match the number of bits set in Sky Light Mask
Sky Light arrays Length Array VarInt Length of the following array in bytes (always 2048)
Sky Light array Byte Array (2048) There is 1 array for each bit set to true in the sky light mask, starting with the lowest value. Half a byte per light value.
Block Light array count VarInt Number of entries in the following array; should match the number of bits set in Block Light Mask
Block Light arrays Length Array VarInt Length of the following array in bytes (always 2048)
Block Light array Byte Array (2048) There is 1 array for each bit set to true in the block light mask, starting with the lowest value. Half a byte per light value.

A bit will never be set in both the block light mask and the empty block light mask, though it may be present in neither of them (if the block light does not need to be updated for the corresponding chunk section). The same applies to the sky light mask and the empty sky light mask.

Login (play)

Huh.png The following information needs to be added to this page:
Although the number of portal cooldown ticks is included in this packet, the whole portal usage process is still dictated entirely by the server. What kind of effect does this value have on the client, if any?

See Protocol Encryption for information on logging in.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x2B

resource:
login
Play Client Entity ID Int The player's Entity ID (EID).
Is hardcore Boolean
Dimension Count VarInt Size of the following array.
Dimension Names Array of Identifier Identifiers for all dimensions on the server.
Max Players VarInt Was once used by the client to draw the player list, but now is ignored.
View Distance VarInt Render distance (2-32).
Simulation Distance VarInt The distance that the client will process specific things, such as entities.
Reduced Debug Info Boolean If true, a Notchian client shows reduced information on the debug screen. For servers in development, this should almost always be false.
Enable respawn screen Boolean Set to false when the doImmediateRespawn gamerule is true.
Do limited crafting Boolean Whether players can only craft recipes they have already unlocked. Currently unused by the client.
Dimension Type VarInt The ID of the type of dimension in the minecraft:dimension_type registry, defined by the Registry Data packet.
Dimension Name Identifier Name of the dimension being spawned into.
Hashed seed Long First 8 bytes of the SHA-256 hash of the world's seed. Used client side for biome noise
Game mode Unsigned Byte 0: Survival, 1: Creative, 2: Adventure, 3: Spectator.
Previous Game mode Byte -1: Undefined (null), 0: Survival, 1: Creative, 2: Adventure, 3: Spectator. The previous game mode. Vanilla client uses this for the debug (F3 + N & F3 + F4) game mode switch. (More information needed)
Is Debug Boolean True if the world is a debug mode world; debug mode worlds cannot be modified and have predefined blocks.
Is Flat Boolean True if the world is a superflat world; flat worlds have different void fog and a horizon at y=0 instead of y=63.
Has death location Boolean If true, then the next two fields are present.
Death dimension name Optional Identifier Name of the dimension the player died in.
Death location Optional Position The location that the player died at.
Portal cooldown VarInt The number of ticks until the player can use the portal again.
Enforces Secure Chat Boolean

Map Data

Updates a rectangular area on a map item.

Packet ID State Bound To Field Name Field Type Notes
0x2C Play Client Map ID VarInt Map ID of the map being modified
Scale Byte From 0 for a fully zoomed-in map (1 block per pixel) to 4 for a fully zoomed-out map (16 blocks per pixel)
Locked Boolean True if the map has been locked in a cartography table
Has Icons Boolean
Icon Count Optional VarInt Number of elements in the following array. Only present if previous Boolean is true.
Icon Type Optional Array VarInt Enum See below
X Byte Map coordinates: -128 for furthest left, +127 for furthest right
Z Byte Map coordinates: -128 for highest, +127 for lowest
Direction Byte 0-15
Has Display Name Boolean
Display Name Optional Text Component Only present if previous Boolean is true
Color Patch Columns Unsigned Byte Number of columns updated
Rows Optional Unsigned Byte Only if Columns is more than 0; number of rows updated
X Optional Unsigned Byte Only if Columns is more than 0; x offset of the westernmost column
Z Optional Unsigned Byte Only if Columns is more than 0; z offset of the northernmost row
Length Optional VarInt Only if Columns is more than 0; length of the following array
Data Optional Array of Unsigned Byte Only if Columns is more than 0; see Map item format

For icons, a direction of 0 is a vertical icon and increments by 22.5° (360/16).

Types are based off of rows and columns in map_icons.png:

Icon type Result
0 White arrow (players)
1 Green arrow (item frames)
2 Red arrow
3 Blue arrow
4 White cross
5 Red pointer
6 White circle (off-map players)
7 Small white circle (far-off-map players)
8 Mansion
9 Monument
10 White Banner
11 Orange Banner
12 Magenta Banner
13 Light Blue Banner
14 Yellow Banner
15 Lime Banner
16 Pink Banner
17 Gray Banner
18 Light Gray Banner
19 Cyan Banner
20 Purple Banner
21 Blue Banner
22 Brown Banner
23 Green Banner
24 Red Banner
25 Black Banner
26 Treasure marker

Merchant Offers

The list of trades a villager NPC is offering.

Packet ID State Bound To Field Name Field Type Notes
0x2D Play Client Window ID VarInt The ID of the window that is open; this is an int rather than a byte.
Size VarInt The number of trades in the following array.
Trades Input item 1 Array Trade Item See below. The first item the player has to supply for this villager trade. The count of the item stack is the default "price" of this trade.
Output item Slot The item the player will receive from this villager trade.
Input item 2 Optional Trade Item The second item the player has to supply for this villager trade. May be an empty slot.
Trade disabled Boolean True if the trade is disabled; false if the trade is enabled.
Number of trade uses Int Number of times the trade has been used so far. If equal to the maximum number of trades, the client will display a red X.
Maximum number of trade uses Int Number of times this trade can be used before it's exhausted.
XP Int Amount of XP the villager will earn each time the trade is used.
Special Price Int Can be zero or negative. The number is added to the price when an item is discounted due to player reputation or other effects.
Price Multiplier Float Can be low (0.05) or high (0.2). Determines how much demand, player reputation, and temporary effects will adjust the price.
Demand Int If positive, causes the price to increase. Negative values seem to be treated the same as zero.
Villager level VarInt Appears on the trade GUI; meaning comes from the translation key merchant.level. + level.

1: Novice, 2: Apprentice, 3: Journeyman, 4: Expert, 5: Master.

Experience VarInt Total experience for this villager (always 0 for the wandering trader).
Is regular villager Boolean True if this is a regular villager; false for the wandering trader. When false, hides the villager level and some other GUI elements.
Can restock Boolean True for regular villagers and false for the wandering trader. If true, the "Villagers restock up to two times per day." message is displayed when hovering over disabled trades.

Trade Item:

Field Name Field Type Meaning
Item ID VarInt The item ID. Item IDs are distinct from block IDs; see Data Generators for more information.
Item Count VarInt The item count.
Size VarInt The number of components in the following array.
Components Component type Array VarInt Enum The type of component. See Structured components for more detail.
Component data Varies The component-dependent data. See Structured components for more detail.

Modifiers can increase or decrease the number of items for the first input slot. The second input slot and the output slot never change the number of items. The number of items may never be less than 1, and never more than the stack size. If special price and demand are both zero, only the default price is displayed. If either is non-zero, then the adjusted price is displayed next to the crossed-out default price. The adjusted prices is calculated as follows:

Adjusted price = default price + floor(default price x multiplier x demand) + special price

The merchant UI, for reference

Update Entity Position

This packet is sent by the server when an entity moves a small distance. The change in position is represented as a fixed-point number with 12 fraction bits and 4 integer bits. As such, the maximum movement distance along each axis is 8 blocks in the negative direction, or 7.999755859375 blocks in the positive direction. If the movement exceeds these limits, Teleport Entity should be sent instead.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x2E

resource:
move_entity_pos
Play Client Entity ID VarInt
Delta X Short Change in X position as currentX * 4096 - prevX * 4096.
Delta Y Short Change in Y position as currentY * 4096 - prevY * 4096.
Delta Z Short Change in Z position as currentZ * 4096 - prevZ * 4096.
On Ground Boolean

Update Entity Position and Rotation

This packet is sent by the server when an entity rotates and moves. See #Update Entity Position for how the position is encoded.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x2F

resource:
move_entity_pos_rot
Play Client Entity ID VarInt
Delta X Short Change in X position as currentX * 4096 - prevX * 4096.
Delta Y Short Change in Y position as currentY * 4096 - prevY * 4096.
Delta Z Short Change in Z position as currentZ * 4096 - prevZ * 4096.
Yaw Angle New angle, not a delta.
Pitch Angle New angle, not a delta.
On Ground Boolean

Update Entity Rotation

This packet is sent by the server when an entity rotates.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x30

resource:
move_entity_rot
Play Client Entity ID VarInt
Yaw Angle New angle, not a delta.
Pitch Angle New angle, not a delta.
On Ground Boolean

Move Vehicle

Note that all fields use absolute positioning and do not allow for relative positioning.

Packet ID State Bound To Field Name Field Type Notes
0x31 Play Client X Double Absolute position (X coordinate).
Y Double Absolute position (Y coordinate).
Z Double Absolute position (Z coordinate).
Yaw Float Absolute rotation on the vertical axis, in degrees.
Pitch Float Absolute rotation on the horizontal axis, in degrees.

Open Book

Sent when a player right clicks with a signed book. This tells the client to open the book GUI.

Packet ID State Bound To Field Name Field Type Notes
0x32 Play Client Hand VarInt Enum 0: Main hand, 1: Off hand .

Open Screen

This is sent to the client when it should open an inventory, such as a chest, workbench, furnace, or other container. Resending this packet with already existing window id, will update the window title and window type without closing the window.

This message is not sent to clients opening their own inventory, nor do clients inform the server in any way when doing so. From the server's perspective, the inventory is always "open" whenever no other windows are.

For horses, use Open Horse Screen.

Packet ID State Bound To Field Name Field Type Notes
0x33 Play Client Window ID VarInt An identifier for the window to be displayed. Notchian server implementation is a counter, starting at 1. There can only be one window at a time; this is only used to ignore outdated packets targeting already-closed windows. Note also that the Window ID field in most other packets is only a single byte, and indeed, the Notchian server wraps around after 100.
Window Type VarInt The window type to use for display. Contained in the minecraft:menu registry; see Inventory for the different values.
Window Title Text Component The title of the window.

Open Sign Editor

Sent when the client has placed a sign and is allowed to send Update Sign. There must already be a sign at the given location (which the client does not do automatically) - send a Block Update first.

Packet ID State Bound To Field Name Field Type Notes
0x34 Play Client Location Position
Is Front Text Boolean Whether the opened editor is for the front or on the back of the sign

Ping (play)

Packet is not used by the Notchian server. When sent to the client, client responds with a Pong packet with the same id.

Packet ID State Bound To Field Name Field Type Notes
0x35 Play Client ID Int

Ping Response (play)

Packet ID State Bound To Field Name Field Type Notes
0x36 Play Client Payload Long Should be the same as sent by the client.

Place Ghost Recipe

Response to the serverbound packet (Place Recipe), with the same recipe ID. Appears to be used to notify the UI.

Packet ID State Bound To Field Name Field Type Notes
0x37 Play Client Window ID Byte
Recipe Identifier A recipe ID.

Player Abilities (clientbound)

The latter 2 floats are used to indicate the flying speed and field of view respectively, while the first byte is used to determine the value of 4 booleans.

Packet ID State Bound To Field Name Field Type Notes
0x38 Play Client Flags Byte Bit field, see below.
Flying Speed Float 0.05 by default.
Field of View Modifier Float Modifies the field of view, like a speed potion. A Notchian server will use the same value as the movement speed sent in the Update Attributes packet, which defaults to 0.1 for players.

About the flags:

Field Bit
Invulnerable 0x01
Flying 0x02
Allow Flying 0x04
Creative Mode (Instant Break) 0x08

Player Chat Message

Main article: Chat

Sends the client a chat message from a player.

Currently a lot is unknown about this packet, blank descriptions are for those that are unknown

Packet ID State Bound To Sector Field Name Field Type Notes
protocol:
0x39

resource:
player_chat
Play Client Header Sender UUID Used by the Notchian client for the disableChat launch option. Setting both longs to 0 will always display the message regardless of the setting.
Index VarInt
Message Signature Present Boolean States if a message signature is present
Message Signature bytes Optional Byte Array (256) Only present if Message Signature Present is true. Cryptography, the signature consists of the Sender UUID, Session UUID from the Player Session packet, Index, Salt, Timestamp in epoch seconds, the length of the original chat content, the original content itself, the length of Previous Messages, and all of the Previous message signatures. These values are hashed with SHA-256 and signed using the RSA cryptosystem. Modifying any of these values in the packet will cause this signature to fail. This buffer is always 256 bytes long and it is not length-prefixed.
Body Message String (256) Raw (optionally) signed sent message content.

This is used as the content parameter when formatting the message on the client.

Timestamp Long Represents the time the message was signed as milliseconds since the epoch, used to check if the message was received within 2 minutes of it being sent.
Salt Long Cryptography, used for validating the message signature.
Previous Messages Total Previous Messages VarInt The maximum length is 20 in Notchian client.
Array (20) Message ID VarInt The message Id + 1, used for validating message signature. The next field is present only when value of this field is equal to 0.
Signature Optional Byte Array (256) The previous message's signature. Contains the same type of data as Message Signature bytes (256 bytes) above. Not length-prefxied.
Other Unsigned Content Present Boolean True if the next field is present
Unsigned Content Optional Text Component
Filter Type VarInt Enum If the message has been filtered
Filter Type Bits Optional BitSet Only present if the Filter Type is Partially Filtered. Specifies the indexes at which characters in the original message string should be replaced with the # symbol (i.e. filtered) by the Notchian client
Chat Formatting Chat Type VarInt The type of chat in the minecraft:chat_type registry, defined by the Registry Data packet. This should not be 0, meaning it is likely index+1
Sender Name Text Component The name of the one sending the message, usually the sender's display name.

This is used as the sender parameter when formatting the message on the client.

Has Target Name Boolean True if target name is present.
Target Name Optional Text Component The name of the one receiving the message, usually the receiver's display name. Only present if previous boolean is true.

This is used as the target parameter when formatting the message on the client.

Player Chat Handling Logic

Filter Types:

The filter type mask should NOT be specified unless partially filtered is selected

ID Name Description
0 PASS_THROUGH Message is not filtered at all
1 FULLY_FILTERED Message is fully filtered
2 PARTIALLY_FILTERED Only some characters in the message are filtered

End Combat

Unused by the Notchian client. This data was once used for twitch.tv metadata circa 1.8.

Packet ID State Bound To Field Name Field Type Notes
0x3A Play Client Duration VarInt Length of the combat in ticks.

Enter Combat

Unused by the Notchian client. This data was once used for twitch.tv metadata circa 1.8.

Packet ID State Bound To Field Name Field Type Notes
0x3B Play Client no fields

Combat Death

Used to send a respawn screen.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x3C

resource:
player_combat_kill
Play Client Player ID VarInt Entity ID of the player that died (should match the client's entity ID).
Message Text Component The death message.

Player Info Remove

Used by the server to remove players from the player list.

Packet ID State Bound To Field Name Field Type Notes
0x3D Play Client Number of Players VarInt Number of elements in the following array.
Player Player Id Array of UUID UUIDs of players to remove.

Player Info Update

Sent by the server to update the user list (<tab> in the client).

Packet ID State Bound To Field Name Field Type Notes
0x3E Play Client Actions Byte Determines what actions are present.
Number Of Players VarInt Number of elements in the following array.
Players UUID Array UUID The player UUID
Player Actions Array of Player Actions The length of this array is determined by the number of Player Actions that give a non-zero value when applying its mask to the actions flag. For example given the decimal number 5, binary 00000101. The masks 0x01 and 0x04 would return a non-zero value, meaning the Player Actions array would include two actions: Add Player and Update Game Mode.


Player Actions
Action Mask Field Name Type Notes
Add Player 0x01 Name String (16)
Number Of Properties VarInt Number of elements in the following array.
Property Name Array String (32767)
Value String (32767)
Is Signed Boolean
Signature Optional String (32767) Only if Is Signed is true.
Initialize Chat 0x02 Has Signature Data Boolean
Chat session ID UUID Only sent if Has Signature Data is true.
Public key expiry time Long Key expiry time, as a UNIX timestamp in milliseconds. Only sent if Has Signature Data is true.
Encoded public key size VarInt Size of the following array. Only sent if Has Signature Data is true. Maximum length is 512 bytes.
Encoded public key Byte Array (512) The player's public key, in bytes. Only sent if Has Signature Data is true.
Public key signature size VarInt Size of the following array. Only sent if Has Signature Data is true. Maximum length is 4096 bytes.
Public key signature Byte Array (4096) The public key's digital signature. Only sent if Has Signature Data is true.
Update Game Mode 0x04 Game Mode VarInt
Update Listed 0x08 Listed Boolean Whether the player should be listed on the player list.
Update Latency 0x10 Ping VarInt Measured in milliseconds.
Update Display Name 0x20 Has Display Name Boolean
Display Name Optional Text Component Only sent if Has Display Name is true.

The properties included in this packet are the same as in Login Success, for the current player.

Ping values correspond with icons in the following way:

  • A ping that negative (i.e. not known to the server yet) will result in the no connection icon.
  • A ping under 150 milliseconds will result in 5 bars
  • A ping under 300 milliseconds will result in 4 bars
  • A ping under 600 milliseconds will result in 3 bars
  • A ping under 1000 milliseconds (1 second) will result in 2 bars
  • A ping greater than or equal to 1 second will result in 1 bar.

Look At

Used to rotate the client player to face the given location or entity (for /teleport [<targets>] <x> <y> <z> facing).

Packet ID State Bound To Field Name Field Type Notes
0x3F Play Client
Feet/eyes VarInt Enum Values are feet=0, eyes=1. If set to eyes, aims using the head position; otherwise aims using the feet position.
Target x Double x coordinate of the point to face towards.
Target y Double y coordinate of the point to face towards.
Target z Double z coordinate of the point to face towards.
Is entity Boolean If true, additional information about an entity is provided.
Entity ID Optional VarInt Only if is entity is true — the entity to face towards.
Entity feet/eyes Optional VarInt Enum Whether to look at the entity's eyes or feet. Same values and meanings as before, just for the entity's head/feet.

If the entity given by entity ID cannot be found, this packet should be treated as if is entity was false.

Synchronize Player Position

Teleports the client, e.g. during login, when using an ender pearl, in response to invalid move packets, etc.

Due to latency, the server may receive outdated movement packets sent before the client was aware of the teleport. To account for this, the server ignores all movement packets from the client until a Confirm Teleportation packet with an ID matching the one sent in the teleport packet is received.

Yaw is measured in degrees, and does not follow classical trigonometry rules. The unit circle of yaw on the XZ-plane starts at (0, 1) and turns counterclockwise, with 90 at (-1, 0), 180 at (0, -1) and 270 at (1, 0). Additionally, yaw is not clamped to between 0 and 360 degrees; any number is valid, including negative numbers and numbers greater than 360 (see MC-90097).

Pitch is measured in degrees, where 0 is looking straight ahead, -90 is looking straight up, and 90 is looking straight down.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x40

resource:
player_position
Play Client X Double Absolute or relative position, depending on Flags.
Y Double Absolute or relative position, depending on Flags.
Z Double Absolute or relative position, depending on Flags.
Yaw Float Absolute or relative rotation on the X axis, in degrees.
Pitch Float Absolute or relative rotation on the Y axis, in degrees.
Flags Byte Reference the Flags table below. When the value of the this byte masked is zero the field is absolute, otherwise relative.
Teleport ID VarInt Client should confirm this packet with Confirm Teleportation containing the same Teleport ID.
Flags
Field Hex Mask
X 0x01
Y 0x02
Z 0x04
Y_ROT (Pitch) 0x08
X_ROT (Yaw) 0x10

Update Recipe Book

Packet ID State Bound To Field Name Field Type Notes
0x41 Play Client
Action VarInt 0: init, 1: add, 2: remove.
Crafting Recipe Book Open Boolean If true, then the crafting recipe book will be open when the player opens its inventory.
Crafting Recipe Book Filter Active Boolean If true, then the filtering option is active when the players opens its inventory.
Smelting Recipe Book Open Boolean If true, then the smelting recipe book will be open when the player opens its inventory.
Smelting Recipe Book Filter Active Boolean If true, then the filtering option is active when the players opens its inventory.
Blast Furnace Recipe Book Open Boolean If true, then the blast furnace recipe book will be open when the player opens its inventory.
Blast Furnace Recipe Book Filter Active Boolean If true, then the filtering option is active when the players opens its inventory.
Smoker Recipe Book Open Boolean If true, then the smoker recipe book will be open when the player opens its inventory.
Smoker Recipe Book Filter Active Boolean If true, then the filtering option is active when the players opens its inventory.
Array size 1 VarInt Number of elements in the following array.
Recipe IDs Array of Identifier
Array size 2 Optional VarInt Number of elements in the following array, only present if action is 0 (init).
Recipe IDs Optional Array of Identifier Only present if mode is 0 (init)

Action:

  • 0 (init) = All the recipes in list 1 will be tagged as displayed, and all the recipes in list 2 will be added to the recipe book. Recipes that aren't tagged will be shown in the notification.
  • 1 (add) = All the recipes in the list are added to the recipe book and their icons will be shown in the notification.
  • 2 (remove) = Remove all the recipes in the list. This allows them to be re-displayed when they are re-added.

Remove Entities

Sent by the server when an entity is to be destroyed on the client.

Packet ID State Bound To Field Name Field Type Notes
0x42 Play Client Count VarInt Number of elements in the following array.
Entity IDs Array of VarInt The list of entities to destroy.

Remove Entity Effect

Packet ID State Bound To Field Name Field Type Notes
0x43 Play Client Entity ID VarInt
Effect ID VarInt See this table.

Reset Score

This is sent to the client when it should remove a scoreboard item.

Packet ID State Bound To Field Name Field Type Notes
0x44 Play Client Entity Name String (32767) The entity whose score this is. For players, this is their username; for other entities, it is their UUID.
Has Objective Name Boolean Whether the score should be removed for the specified objective, or for all of them.
Objective Name Optional String (32767) The name of the objective the score belongs to. Only present if the previous field is true.

Remove Resource Pack (play)

Packet ID State Bound To Field Name Field Type Notes
0x45 Play Client Has UUID Boolean Whether a specific resource pack should be removed, or all of them.
UUID Optional UUID The UUID of the resource pack to be removed. Only present if the previous field is true.

Add Resource Pack (play)

Packet ID State Bound To Field Name Field Type Notes
0x46 Play Client UUID UUID The unique identifier of the resource pack.
URL String (32767) The URL to the resource pack.
Hash String (40) A 40 character hexadecimal, case-insensitive SHA-1 hash of the resource pack file.
If it's not a 40 character hexadecimal string, the client will not use it for hash verification and likely waste bandwidth.
Forced Boolean The Notchian client will be forced to use the resource pack from the server. If they decline they will be kicked from the server.
Has Prompt Message Boolean Whether a custom message should be used on the resource pack prompt.
Prompt Message Optional Text Component This is shown in the prompt making the client accept or decline the resource pack. Only present if the previous field is true.

Respawn

Huh.png The following information needs to be added to this page:
Although the number of portal cooldown ticks is included in this packet, the whole portal usage process is still dictated entirely by the server. What kind of effect does this value have on the client, if any?

To change the player's dimension (overworld/nether/end), send them a respawn packet with the appropriate dimension, followed by prechunks/chunks for the new dimension, and finally a position and look packet. You do not need to unload chunks, the client will do it automatically.

Packet ID State Bound To Field Name Field Type Notes
0x47 Play Client Dimension Type VarInt The ID of type of dimension in the minecraft:dimension_type registry, defined by the Registry Data packet.
Dimension Name Identifier Name of the dimension being spawned into.
Hashed seed Long First 8 bytes of the SHA-256 hash of the world's seed. Used client side for biome noise
Game mode Unsigned Byte 0: Survival, 1: Creative, 2: Adventure, 3: Spectator.
Previous Game mode Byte -1: Undefined (null), 0: Survival, 1: Creative, 2: Adventure, 3: Spectator. The previous game mode. Vanilla client uses this for the debug (F3 + N & F3 + F4) game mode switch. (More information needed)
Is Debug Boolean True if the world is a debug mode world; debug mode worlds cannot be modified and have predefined blocks.
Is Flat Boolean True if the world is a superflat world; flat worlds have different void fog and a horizon at y=0 instead of y=63.
Has death location Boolean If true, then the next two fields are present.
Death dimension Name Optional Identifier Name of the dimension the player died in.
Death location Optional Position The location that the player died at.
Portal cooldown VarInt The number of ticks until the player can use the portal again.
Data kept Byte Bit mask. 0x01: Keep attributes, 0x02: Keep metadata. Tells which data should be kept on the client side once the player has respawned.

In the Notchian implementation, this is context dependent:

  • normal respawns (after death) keep no data;
  • exiting the end poem/credits keeps the attributes;
  • other dimension changes (portals or teleports) keep all data.

Warning.png Avoid changing player's dimension to same dimension they were already in unless they are dead. If you change the dimension to one they are already in, weird bugs can occur, such as the player being unable to attack other players in new world (until they die and respawn).

Before 1.16, if you must respawn a player in the same dimension without killing them, send two respawn packets, one to a different world and then another to the world you want. You do not need to complete the first respawn; it only matters that you send two packets.

Set Head Rotation

Changes the direction an entity's head is facing.

While sending the Entity Look packet changes the vertical rotation of the head, sending this packet appears to be necessary to rotate the head horizontally.

Packet ID State Bound To Field Name Field Type Notes
0x48 Play Client Entity ID VarInt
Head Yaw Angle New angle, not a delta.

Update Section Blocks

Fired whenever 2 or more blocks are changed within the same chunk on the same tick.

Warning.png Changing blocks in chunks not loaded by the client is unsafe (see note on Block Update).

Packet ID State Bound To Field Name Field Type Notes
0x49 Play Client Chunk section position Long Chunk section coordinate (encoded chunk x and z with each 22 bits, and section y with 20 bits, from left to right).
Blocks array size VarInt Number of elements in the following array.
Blocks Array of VarLong Each entry is composed of the block state id, shifted left by 12, and the relative block position in the chunk section (4 bits for x, z, and y, from left to right).

Chunk section position is encoded:

((sectionX & 0x3FFFFF) << 42) | (sectionY & 0xFFFFF) | ((sectionZ & 0x3FFFFF) << 20);

and decoded:

sectionX = long >> 42;
sectionY = long << 44 >> 44;
sectionZ = long << 22 >> 42;

Blocks are encoded:

blockStateId << 12 | (blockLocalX << 8 | blockLocalZ << 4 | blockLocalY)
//Uses the local position of the given block position relative to its respective chunk section

and decoded:

blockStateId = long >> 12;
blockLocalX = (long >> 8) & 0xF;
blockLocalY = long & 0xF;
blockLocalZ = (long >> 4) & 0xF;

Select Advancements Tab

Sent by the server to indicate that the client should switch advancement tab. Sent either when the client switches tab in the GUI or when an advancement in another tab is made.

Packet ID State Bound To Field Name Field Type Notes
0x4A Play Client Has id Boolean Indicates if the next field is present.
Identifier Optional Identifier See below.

The Identifier can be one of the following:

Identifier
minecraft:story/root
minecraft:nether/root
minecraft:end/root
minecraft:adventure/root
minecraft:husbandry/root

If no or an invalid identifier is sent, the client will switch to the first tab in the GUI.

Server Data

Packet ID State Bound To Field Name Field Type Notes
0x4B Play Client MOTD Text Component
Has Icon Boolean
Size Optional VarInt Number of bytes in the following array. Only present if Has Icon is true.
Icon Optional Byte Array Icon bytes in the PNG format. Only present is Has Icon is true.

Set Action Bar Text

Displays a message above the hotbar. Equivalent to System Chat Message with Overlay set to true, except that chat message blocking isn't performed. Used by the Notchian server only to implement the /title command.

Packet ID State Bound To Field Name Field Type Notes
0x4C Play Client Action bar text Text Component

Set Border Center

Packet ID State Bound To Field Name Field Type Notes
0x4D Play Client X Double
Z Double

Set Border Lerp Size

Packet ID State Bound To Field Name Field Type Notes
0x4E Play Client Old Diameter Double Current length of a single side of the world border, in meters.
New Diameter Double Target length of a single side of the world border, in meters.
Speed VarLong Number of real-time milliseconds until New Diameter is reached. It appears that Notchian server does not sync world border speed to game ticks, so it gets out of sync with server lag. If the world border is not moving, this is set to 0.

Set Border Size

Packet ID State Bound To Field Name Field Type Notes
0x4F Play Client Diameter Double Length of a single side of the world border, in meters.

Set Border Warning Delay

Packet ID State Bound To Field Name Field Type Notes
0x50 Play Client Warning Time VarInt In seconds as set by /worldborder warning time.

Set Border Warning Distance

Packet ID State Bound To Field Name Field Type Notes
0x51 Play Client Warning Blocks VarInt In meters.

Set Camera

Sets the entity that the player renders from. This is normally used when the player left-clicks an entity while in spectator mode.

The player's camera will move with the entity and look where it is looking. The entity is often another player, but can be any type of entity. The player is unable to move this entity (move packets will act as if they are coming from the other entity).

If the given entity is not loaded by the player, this packet is ignored. To return control to the player, send this packet with their entity ID.

The Notchian server resets this (sends it back to the default entity) whenever the spectated entity is killed or the player sneaks, but only if they were spectating an entity. It also sends this packet whenever the player switches out of spectator mode (even if they weren't spectating an entity).

Packet ID State Bound To Field Name Field Type Notes
0x52 Play Client Camera ID VarInt ID of the entity to set the client's camera to.

The notchian client also loads certain shaders for given entities:

  • Creeper → shaders/post/creeper.json
  • Spider (and cave spider) → shaders/post/spider.json
  • Enderman → shaders/post/invert.json
  • Anything else → the current shader is unloaded

Set Held Item (clientbound)

Sent to change the player's slot selection.

Packet ID State Bound To Field Name Field Type Notes
0x53 Play Client Slot Byte The slot which the player has selected (0–8).

Set Center Chunk

Sets the center position of the client's chunk loading area. The area is square-shaped, spanning 2 × server view distance + 7 chunks on both axes (width, not radius!). Since the area's width is always an odd number, there is no ambiguity as to which chunk is the center.

The Notchian client ignores attempts to send chunks located outside the loading area, and immediately unloads any existing chunks no longer inside it.

The center chunk is normally the chunk the player is in, but apart from the implications on chunk loading, the (Notchian) client takes no issue with this not being the case. Indeed, as long as chunks are sent only within the default loading area centered on the world origin, it is not necessary to send this packet at all. This may be useful for servers with small bounded worlds, such as minigames, since it ensures chunks never need to be resent after the client has joined, saving on bandwidth.

The Notchian server sends this packet whenever the player moves across a chunk border horizontally, and also (according to testing) for any integer change in the vertical axis, even if it doesn't go across a chunk section border.

Packet ID State Bound To Field Name Field Type Notes
0x54 Play Client Chunk X VarInt Chunk X coordinate of the loading area center.
Chunk Z VarInt Chunk Z coordinate of the loading area center.

Set Render Distance

Sent by the integrated singleplayer server when changing render distance. This packet is sent by the server when the client reappears in the overworld after leaving the end.

Packet ID State Bound To Field Name Field Type Notes
0x55 Play Client View Distance VarInt Render distance (2-32).

Set Default Spawn Position

Sent by the server after login to specify the coordinates of the spawn point (the point at which players spawn at, and which the compass points to). It can be sent at any time to update the point compasses point at.

The client uses this as the default position of the player upon spawning, though it's a good idea to always override this default by sending Synchronize Player Position. When converting the position to floating point, 0.5 is added to the x and z coordinates and 1.0 to the y coordinate, so as to place the player centered on top of the specified block position.

Before receiving this packet, the client uses the default position 8, 64, 8, and angle 0.0 (resulting in a default player spawn position of 8.5, 65.0, 8.5).

Packet ID State Bound To Field Name Field Type Notes
0x56 Play Client Location Position Spawn location.
Angle Float The angle at which to respawn at.

Display Objective

This is sent to the client when it should display a scoreboard.

Packet ID State Bound To Field Name Field Type Notes
0x57 Play Client Position VarInt The position of the scoreboard. 0: list, 1: sidebar, 2: below name, 3 - 18: team specific sidebar, indexed as 3 + team color.
Score Name String (32767) The unique name for the scoreboard to be displayed.

Set Entity Metadata

Updates one or more metadata properties for an existing entity. Any properties not included in the Metadata field are left unchanged.

Packet ID State Bound To Field Name Field Type Notes
0x58 Play Client Entity ID VarInt
Metadata Entity Metadata

Link Entities

This packet is sent when an entity has been leashed to another entity.

Packet ID State Bound To Field Name Field Type Notes
0x59 Play Client Attached Entity ID Int Attached entity's EID.
Holding Entity ID Int ID of the entity holding the lead. Set to -1 to detach.

Set Entity Velocity

Velocity is in units of 1/8000 of a block per server tick (50ms); for example, -1343 would move (-1343 / 8000) = −0.167875 blocks per tick (or −3.3575 blocks per second).

Packet ID State Bound To Field Name Field Type Notes
0x5A Play Client Entity ID VarInt
Velocity X Short Velocity on the X axis.
Velocity Y Short Velocity on the Y axis.
Velocity Z Short Velocity on the Z axis.

Set Equipment

Packet ID State Bound To Field Name Field Type Notes
0x5B Play Client Entity ID VarInt Entity's ID.
Equipment Slot Array Byte Enum Equipment slot (see below). Also has the top bit set if another entry follows, and otherwise unset if this is the last item in the array.
Item Slot

Equipment slot can be one of the following:

ID Equipment slot
0 Main hand
1 Off hand
2 Boots
3 Leggings
4 Chestplate
5 Helmet
6 Body

Set Experience

Sent by the server when the client should change experience levels.

Packet ID State Bound To Field Name Field Type Notes
0x5C Play Client Experience bar Float Between 0 and 1.
Level VarInt
Total Experience VarInt See Experience#Leveling up on the Minecraft Wiki for Total Experience to Level conversion.

Set Health

Sent by the server to set the health of the player it is sent to.

Food saturation acts as a food “overcharge”. Food values will not decrease while the saturation is over zero. New players logging in or respawning automatically get a saturation of 5.0. Eating food increases the saturation as well as the food bar.

Packet ID State Bound To Field Name Field Type Notes
0x5D Play Client Health Float 0 or less = dead, 20 = full HP.
Food VarInt 0–20.
Food Saturation Float Seems to vary from 0.0 to 5.0 in integer increments.

Update Objectives

This is sent to the client when it should create a new scoreboard objective or remove one.

Packet ID State Bound To Field Name Field Type Notes
0x5E Play Client Objective Name String (32767) A unique name for the objective.
Mode Byte 0 to create the scoreboard. 1 to remove the scoreboard. 2 to update the display text.
Objective Value Optional Text Component Only if mode is 0 or 2.The text to be displayed for the score.
Type Optional VarInt Enum Only if mode is 0 or 2. 0 = "integer", 1 = "hearts".
Has Number Format Optional Boolean Only if mode is 0 or 2. Whether this objective has a set number format for the scores.
Number Format Optional VarInt Enum Only if mode is 0 or 2 and the previous boolean is true. Determines how the score number should be formatted.
Number Format Field Name
0: blank no fields Show nothing.
1: styled Styling Compound Tag The styling to be used when formatting the score number. Contains the text component styling fields.
2: fixed Content Text Component The text to be used as placeholder.

Set Passengers

Packet ID State Bound To Field Name Field Type Notes
0x5F Play Client Entity ID VarInt Vehicle's EID.
Passenger Count VarInt Number of elements in the following array.
Passengers Array of VarInt EIDs of entity's passengers.

Update Teams

Creates and updates teams.

Packet ID State Bound To Field Name Field Type Notes
0x60 Play Client Team Name String (32767) A unique name for the team. (Shared with scoreboard).
Method Byte Determines the layout of the remaining packet.
0: create team Team Display Name Text Component
Friendly Flags Byte Bit mask. 0x01: Allow friendly fire, 0x02: can see invisible players on same team.
Name Tag Visibility String Enum (40) always, hideForOtherTeams, hideForOwnTeam, never.
Collision Rule String Enum (40) always, pushOtherTeams, pushOwnTeam, never.
Team Color VarInt Enum Used to color the name of players on the team; see below.
Team Prefix Text Component Displayed before the names of players that are part of this team.
Team Suffix Text Component Displayed after the names of players that are part of this team.
Entity Count VarInt Number of elements in the following array.
Entities Array of String (32767) Identifiers for the entities in this team. For players, this is their username; for other entities, it is their UUID.
1: remove team no fields no fields
2: update team info Team Display Name Text Component
Friendly Flags Byte Bit mask. 0x01: Allow friendly fire, 0x02: can see invisible entities on same team.
Name Tag Visibility String Enum (40) always, hideForOtherTeams, hideForOwnTeam, never
Collision Rule String Enum (40) always, pushOtherTeams, pushOwnTeam, never
Team Color VarInt Enum Used to color the name of players on the team; see below.
Team Prefix Text Component Displayed before the names of players that are part of this team.
Team Suffix Text Component Displayed after the names of players that are part of this team.
3: add entities to team Entity Count VarInt Number of elements in the following array.
Entities Array of String (32767) Identifiers for the added entities. For players, this is their username; for other entities, it is their UUID.
4: remove entities from team Entity Count VarInt Number of elements in the following array.
Entities Array of String (32767) Identifiers for the removed entities. For players, this is their username; for other entities, it is their UUID.

Team Color: The color of a team defines how the names of the team members are visualized; any formatting code can be used. The following table lists all the possible values.

ID Formatting
0-15 Color formatting, same values as in Text formatting#Colors.
16 Obfuscated
17 Bold
18 Strikethrough
19 Underlined
20 Italic
21 Reset

Update Score

This is sent to the client when it should update a scoreboard item.

Packet ID State Bound To Field Name Field Type Notes
0x61 Play Client Entity Name String (32767) The entity whose score this is. For players, this is their username; for other entities, it is their UUID.
Objective Name String (32767) The name of the objective the score belongs to.
Value VarInt The score to be displayed next to the entry.
Has Display Name Boolean Whether this score has a custom display name.
Display Name Optional Text Component The custom display name. Only present if the previous boolean is true.
Has Number Format Boolean Whether this score has a set number format. This overrides the number format set on the objective, if any.
Number Format Optional VarInt Enum Determines how the score number should be formatted. Only present if the previous boolean is true.
Number Format Field Name
0: blank no fields Show nothing.
1: styled Styling Compound Tag The styling to be used when formatting the score number. Contains the text component styling fields.
2: fixed Content Text Component The text to be used as placeholder.

Set Simulation Distance

Packet ID State Bound To Field Name Field Type Notes
0x62 Play Client Simulation Distance VarInt The distance that the client will process specific things, such as entities.

Set Subtitle Text

Packet ID State Bound To Field Name Field Type Notes
0x63 Play Client Subtitle Text Text Component

Update Time

Time is based on ticks, where 20 ticks happen every second. There are 24000 ticks in a day, making Minecraft days exactly 20 minutes long.

The time of day is based on the timestamp modulo 24000. 0 is sunrise, 6000 is noon, 12000 is sunset, and 18000 is midnight.

The default SMP server increments the time by 20 every second.

Packet ID State Bound To Field Name Field Type Notes
0x64 Play Client World Age Long In ticks; not changed by server commands.
Time of day Long The world (or region) time, in ticks. If negative the sun will stop moving at the Math.abs of the time.

Set Title Text

Packet ID State Bound To Field Name Field Type Notes
0x65 Play Client Title Text Text Component

Set Title Animation Times

Packet ID State Bound To Field Name Field Type Notes
0x66 Play Client Fade In Int Ticks to spend fading in.
Stay Int Ticks to keep the title displayed.
Fade Out Int Ticks to spend fading out, not when to start fading out.

Entity Sound Effect

Plays a sound effect from an entity, either by hardcoded ID or Identifier. Sound IDs and names can be found here.

Warning.png Numeric sound effect IDs are liable to change between versions

Packet ID State Bound To Field Name Field Type Notes
0x67 Play Client Sound ID VarInt Represents the Sound ID + 1. If the value is 0, the packet contains a sound specified by Identifier.
Sound Name Optional Identifier Only present if Sound ID is 0
Has Fixed Range Optional Boolean Only present if Sound ID is 0.
Range Optional Float The fixed range of the sound. Only present if previous boolean is true and Sound ID is 0.
Sound Category VarInt Enum The category that this sound will be played from (current categories).
Entity ID VarInt
Volume Float 1.0 is 100%, capped between 0.0 and 1.0 by Notchian clients.
Pitch Float Float between 0.5 and 2.0 by Notchian clients.
Seed Long Seed used to pick sound variant.

Sound Effect

Plays a sound effect at the given location, either by hardcoded ID or Identifier. Sound IDs and names can be found here.

Warning.png Numeric sound effect IDs are liable to change between versions

Packet ID State Bound To Field Name Field Type Notes
0x68 Play Client Sound ID VarInt Represents the Sound ID + 1. If the value is 0, the packet contains a sound specified by Identifier.
Sound Name Optional Identifier Only present if Sound ID is 0
Has Fixed Range Optional Boolean Only present if Sound ID is 0.
Range Optional Float The fixed range of the sound. Only present if previous boolean is true and Sound ID is 0.
Sound Category VarInt Enum The category that this sound will be played from (current categories).
Effect Position X Int Effect X multiplied by 8 (fixed-point number with only 3 bits dedicated to the fractional part).
Effect Position Y Int Effect Y multiplied by 8 (fixed-point number with only 3 bits dedicated to the fractional part).
Effect Position Z Int Effect Z multiplied by 8 (fixed-point number with only 3 bits dedicated to the fractional part).
Volume Float 1.0 is 100%, capped between 0.0 and 1.0 by Notchian clients.
Pitch Float Float between 0.5 and 2.0 by Notchian clients.
Seed Long Seed used to pick sound variant.

Start Configuration

Sent during gameplay in order to redo the configuration process. The client must respond with Acknowledge Configuration for the process to start.

Packet ID State Bound To Field Name Field Type Notes
0x69 Play Client no fields

This packet switches the connection state to configuration.

Stop Sound

Packet ID State Bound To Field Name Field Type Notes
0x6A Play Client Flags Byte Controls which fields are present.
Source Optional VarInt Enum Only if flags is 3 or 1 (bit mask 0x1). See below. If not present, then sounds from all sources are cleared.
Sound Optional Identifier Only if flags is 2 or 3 (bit mask 0x2). A sound effect name, see Custom Sound Effect. If not present, then all sounds are cleared.

Categories:

Name Value
master 0
music 1
record 2
weather 3
block 4
hostile 5
neutral 6
player 7
ambient 8
voice 9

Store Cookie (play)

Stores some arbitrary data on the client, which persists between server transfers. The Notchian client only accepts cookies of up to 5 kiB in size.

Packet ID State Bound To Field Name Field Type Notes
0x6B Play Client Key Identifier The identifier of the cookie.
Payload Length VarInt Length of the following byte array.
Payload Byte Array (5120) The data of the cookie.

System Chat Message

Main article: Chat

Sends the client a raw system message.

Packet ID State Bound To Field Name Field Type Notes
0x6C Play Client Content Text Component Limited to 262144 bytes.
Overlay Boolean Whether the message is an actionbar or chat message. See also #Set Action Bar Text.

Set Tab List Header And Footer

This packet may be used by custom servers to display additional information above/below the player list. It is never sent by the Notchian server.

Packet ID State Bound To Field Name Field Type Notes
0x6D Play Client Header Text Component To remove the header, send a empty text component: {"text":""}.
Footer Text Component To remove the footer, send a empty text component: {"text":""}.

Tag Query Response

Sent in response to Query Block Entity Tag or Query Entity Tag.

Packet ID State Bound To Field Name Field Type Notes
0x6E Play Client Transaction ID VarInt Can be compared to the one sent in the original query packet.
NBT NBT The NBT of the block or entity. May be a TAG_END (0) in which case no NBT is present.

Pickup Item

Sent by the server when someone picks up an item lying on the ground — its sole purpose appears to be the animation of the item flying towards you. It doesn't destroy the entity in the client memory, and it doesn't add it to your inventory. The server only checks for items to be picked up after each Set Player Position (and Set Player Position And Rotation) packet sent by the client. The collector entity can be any entity; it does not have to be a player. The collected entity also can be any entity, but the Notchian server only uses this for items, experience orbs, and the different varieties of arrows.

Packet ID State Bound To Field Name Field Type Notes
0x6F Play Client Collected Entity ID VarInt
Collector Entity ID VarInt
Pickup Item Count VarInt Seems to be 1 for XP orbs, otherwise the number of items in the stack.

Teleport Entity

This packet is sent by the server when an entity moves more than 8 blocks.

Packet ID State Bound To Field Name Field Type Notes
0x70 Play Client Entity ID VarInt
X Double
Y Double
Z Double
Yaw Angle (Y Rot)New angle, not a delta.
Pitch Angle (X Rot)New angle, not a delta.
On Ground Boolean

Set Ticking State

Used to adjust the ticking rate of the client, and whether it's frozen.

Packet ID State Bound To Field Name Field Type Notes
0x71 Play Client Tick rate Float
Is frozen Boolean

Step Tick

Advances the client processing by the specified number of ticks. Has no effect unless client ticking is frozen.

Packet ID State Bound To Field Name Field Type Notes
0x72 Play Client Tick steps VarInt

Transfer (play)

Notifies the client that it should transfer to the given server. Cookies previously stored are preserved between server transfers.

Packet ID State Bound To Field Name Field Type Notes
0x73 Play Client Host String The hostname of IP of the server.
Port VarInt The port of the server.

Update Advancements

Packet ID State Bound To Field Name Field Type Notes
0x74 Play Client Reset/Clear Boolean Whether to reset/clear the current advancements.
Mapping size VarInt Size of the following array.
Advancement mapping Key Array Identifier The identifier of the advancement.
Value Advancement See below
List size VarInt Size of the following array.
Identifiers Array of Identifier The identifiers of the advancements that should be removed.
Progress size VarInt Size of the following array.
Progress mapping Key Array Identifier The identifier of the advancement.
Value Advancement progress See below.

Advancement structure:

Field Name Field Type Notes
Has parent Boolean Indicates whether the next field exists.
Parent id Optional Identifier The identifier of the parent advancement.
Has display Boolean Indicates whether the next field exists.
Display data Optional Advancement display See below.
Array length VarInt Number of arrays in the following array.
Requirements Array length 2 Array VarInt Number of elements in the following array.
Requirement Array of String (32767) Array of required criteria.
Sends telemetry data Boolean Whether the client should include this achievement in the telemetry data when it's completed.

The Notchian client only sends data for advancements on the minecraft namespace.

Advancement display:

Field Name Field Type Notes
Title Text Component
Description Text Component
Icon Slot
Frame type VarInt Enum 0 = task, 1 = challenge, 2 = goal.
Flags Int 0x01: has background texture; 0x02: show_toast; 0x04: hidden.
Background texture Optional Identifier Background texture location. Only if flags indicates it.
X coord Float
Y coord Float

Advancement progress:

Field Name Field Type Notes
Size VarInt Size of the following array.
Criteria Criterion identifier Array Identifier The identifier of the criterion.
Criterion progress Criterion progress

Criterion progress:

Field Name Field Type Notes
Achieved Boolean If true, next field is present.
Date of achieving Optional Long As returned by Date.getTime.

Update Attributes

Sets attributes on the given entity.

Packet ID State Bound To Field Name Field Type Notes
0x75 Play Client Entity ID VarInt
Number Of Properties VarInt Number of elements in the following array.
Property Id Array VarInt Enum See below.
Value Double See below.
Number Of Modifiers VarInt Number of elements in the following array.
Modifiers Array of Modifier Data See Attribute#Modifiers. Modifier Data defined below.

Known Id values (see also Attribute#Modifiers):

Id Key Default Min Max Label
0 generic.armor 0.0 0.0 30.0 Armor.
1 generic.armor_toughness 0.0 0.0 20.0 Armor Toughness.
2 generic.attack_damage 2.0 0.0 2048.0 Attack Damage.
3 generic.attack_knockback 0.0 0.0 5.0 Attack Knockback.
4 generic.attack_speed 4.0 0.0 1024.0 Attack Speed.
5 generic.block_break_speed 1.0 0.0 1024.0 Block Break Speed.
6 generic.block_interaction_range 4.5 0.0 64.0 Block Interaction Range.
7 generic.entity_interaction_range 3.0 0.0 64.0 Entity Interaction Range.
8 generic.fall_damage_multiplier 1.0 0.0 100.0 Fall Damage Multiplier.
9 generic.flying_speed 0.4 0.0 1024.0 Flying Speed.
10 generic.follow_range 32.0 0.0 2048.0 Follow Range.
11 generic.gravity 0.08 -1.0 1.0 Gravity.
12 generic.jump_strength 0.42 0.0 32.0 Jump Strength.
13 generic.knockback_resistance 0.0 0.0 1.0 Knockback Resistance.
14 generic.luck 0.0 -1024.0 1024.0 Luck.
15 generic.max_absorption 0.0 0.0 2048.0 Max Absorption.
16 generic.max_health 20.0 1.0 1024.0 Max Health.
17 generic.movement_speed 0.7 0.0 1024.0 Movement Speed.
18 generic.safe_fall_distance 3.0 -1024.0 1024.0 Safe Fall Distance.
19 generic.scale 1.0 0.0625 16.0 Scale.
20 zombie.spawn_reinforcements 0.0 0.0 1.0 Spawn Reinforcements Chance.
21 generic.step_height 0.6 0.0 10.0 Step Height.
22 generic.submerged_mining_speed 0.2 0.0 20.0 Submerged Mining Speed.
23 generic.sweeping_damage_ratio 0.0 0.0 1.0 Sweeping Damage Ratio.
24 generic.water_movement_efficiency 0.0 0.0 1.0 Water Movement Efficiency.

Modifier Data structure:

Field Name Field Type Notes
Id Identifier
Amount Double May be positive or negative.
Operation Byte See below.

The operation controls how the base value of the modifier is changed.

  • 0: Add/subtract amount
  • 1: Add/subtract amount percent of the current value
  • 2: Multiply by amount percent

All of the 0's are applied first, and then the 1's, and then the 2's.

Entity Effect

Packet ID State Bound To Field Name Field Type Notes
0x76 Play Client Entity ID VarInt
Effect ID VarInt See this table.
Amplifier VarInt Notchian client displays effect level as Amplifier + 1.
Duration VarInt Duration in ticks. (-1 for infinite)
Flags Byte Bit field, see below.
Huh.png The following information needs to be added to this page:
What exact effect does the blend bit flag have on the client? What happens if it is used on effects besides DARKNESS?

Within flags:

  • 0x01: Is ambient - was the effect spawned from a beacon? All beacon-generated effects are ambient. Ambient effects use a different icon in the HUD (blue border rather than gray). If all effects on an entity are ambient, the "Is potion effect ambient" living metadata field should be set to true. Usually should not be enabled.
  • 0x02: Show particles - should all particles from this effect be hidden? Effects with particles hidden are not included in the calculation of the effect color, and are not rendered on the HUD (but are still rendered within the inventory). Usually should be enabled.
  • 0x04: Show icon - should the icon be displayed on the client? Usually should be enabled.
  • 0x08: Blend - should the effect's hard-coded blending be applied? Currently only used in the DARKNESS effect to apply extra void fog and adjust the gamma value for lighting.


Update Recipes

Packet ID State Bound To Field Name Field Type Notes
0x77 Play Client Num Recipes VarInt Number of elements in the following array.
Recipe Recipe ID Array Identifier
Type ID VarInt Enum The recipe type, see below.
Data Varies Additional data for the recipe.

Recipe types:

ID Type Description Data
0 minecraft:crafting_shaped Shaped crafting recipe. All items must be present in the same pattern (which may be flipped horizontally or translated). As follows:
Name Type Description
Group String (32767) Used to group similar recipes together in the recipe book. Tag is present in recipe JSON.
Category VarInt Enum Building = 0, Redstone = 1, Equipment = 2, Misc = 3
Width VarInt
Height VarInt
Ingredients Array of Ingredient Length is width * height. Indexed by x + (y * width).
Result Slot
Show notification Boolean Show a toast when the recipe is added.
1 minecraft:crafting_shapeless Shapeless crafting recipe. All items in the ingredient list must be present, but in any order/slot. As follows:
Name Type Description
Group String (32767) Used to group similar recipes together in the recipe book. Tag is present in recipe JSON.
Category VarInt Enum Building = 0, Redstone = 1, Equipment = 2, Misc = 3
Ingredient count VarInt Number of elements in the following array.
Ingredients Array of Ingredient.
Result Slot
2 minecraft:crafting_special_armordye Recipe for dying leather armor As follows:
Name Type Description
Category VarInt Enum Building = 0, Redstone = 1, Equipment = 2, Misc = 3
3 minecraft:crafting_special_bookcloning Recipe for copying contents of written books
4 minecraft:crafting_special_mapcloning Recipe for copying maps
5 minecraft:crafting_special_mapextending Recipe for adding paper to maps
6 minecraft:crafting_special_firework_rocket Recipe for making firework rockets
7 minecraft:crafting_special_firework_star Recipe for making firework stars
8 minecraft:crafting_special_firework_star_fade Recipe for making firework stars fade between multiple colors
9 minecraft:crafting_special_tippedarrow Recipe for crafting tipped arrows
10 minecraft:crafting_special_bannerduplicate Recipe for copying banner patterns
11 minecraft:crafting_special_shielddecoration Recipe for applying a banner's pattern to a shield
12 minecraft:crafting_special_shulkerboxcoloring Recipe for recoloring a shulker box
13 minecraft:crafting_special_suspiciousstew Recipe for crafting suspicious stews
14 minecraft:crafting_special_repairitem Recipe for repairing items via crafting
22 minecraft:crafting_decorated_pot Recipe for crafting decorated pots
15 minecraft:smelting Smelting recipe As follows:
Name Type Description
Group String (32767) Used to group similar recipes together in the recipe book.
Category VarInt Enum Food = 0, Blocks = 1, Misc = 2
Ingredient Ingredient
Result Slot
Experience Float
Cooking time VarInt
16 minecraft:blasting Blast furnace recipe
17 minecraft:smoking Smoker recipe
18 minecraft:campfire_cooking Campfire recipe
19 minecraft:stonecutting Stonecutter recipe As follows:
Name Type Description
Group String (32767) Used to group similar recipes together in the recipe book. Tag is present in recipe JSON.
Ingredient Ingredient
Result Slot
20 minecraft:smithing_transform Recipe for smithing netherite gear As follows:
Name Type Description
Template Ingredient The smithing template.
Base Ingredient The base item.
Addition Ingredient The additional ingredient.
Result Slot
21 minecraft:smithing_trim Recipe for applying armor trims As follows:
Name Type Description
Template Ingredient The smithing template.
Base Ingredient The base item.
Addition Ingredient The additional ingredient.

Ingredient is defined as:

Name Type Description
Count VarInt Number of elements in the following array.
Items Array of Slot Any item in this array may be used for the recipe. The count of each item should be 1.

Update Tags (play)

Packet ID State Bound To Field Name Field Type Notes
0x78 Play Client Length of the array VarInt
Array of tags Registry Array Identifier Registry identifier (Vanilla expects tags for the registries minecraft:block, minecraft:item, minecraft:fluid, minecraft:entity_type, and minecraft:game_event)
Array of Tag (See below)

Tag arrays look like:

Field Name Field Type Notes
Length VarInt Number of elements in the following array
Tags Tag name Array Identifier
Count VarInt Number of elements in the following array
Entries Array of VarInt Numeric IDs of the given type (block, item, etc.). This list replaces the previous list of IDs for the given tag. If some preexisting tags are left unmentioned, a warning is printed.

See Tag on the Minecraft Wiki for more information, including a list of vanilla tags.

Projectile Power

Packet ID State Bound To Field Name Field Type Notes
0x79 Play Client Entity ID VarInt
Power Double

Custom Report Details

Contains a list of key-value text entries that are included in any crash or disconnection report generated during connection to the server.

Packet ID State Bound To Field Name Field Type Notes
0x7A Play Client Details Count VarInt (32) The number of details in the following array.
Details Title Array String (128)
Description String (4096)

Server Links

This packet contains a list of links that the Notchian client will display in the menu available from the pause menu. Link labels can be built-in or custom (i.e., any text).

Packet ID State Bound To Field Name Field Type Notes
0x7B Play Client Links Count VarInt The number of links in the following array.
Links Is built-in Array Boolean Determines if the following label is built-in (from enum) or custom (text component).
Label VarInt Enum / Text Component See below.
URL String Valid URL.
ID Name Notes
0 Bug Report Displayed on connection error screen; included as a comment in the disconnection report.
1 Community Guidelines
2 Support
3 Status
4 Feedback
5 Community
6 Website
7 Forums
8 News
9 Announcements

Serverbound

Confirm Teleportation

Sent by client as confirmation of Synchronize Player Position.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x00

resource:
accept_teleportation
Play Server Teleport ID VarInt The ID given by the Synchronize Player Position packet.

Query Block Entity Tag

Used when F3+I is pressed while looking at a block.

Packet ID State Bound To Field Name Field Type Notes
0x01 Play Server Transaction ID VarInt An incremental ID so that the client can verify that the response matches.
Location Position The location of the block to check.

Change Difficulty

Must have at least op level 2 to use. Appears to only be used on singleplayer; the difficulty buttons are still disabled in multiplayer.

Packet ID State Bound To Field Name Field Type Notes
0x02 Play Server New difficulty Byte 0: peaceful, 1: easy, 2: normal, 3: hard .

Acknowledge Message

Packet ID State Bound To Field Name Field Type Notes
0x03 Play Server Message Count VarInt

Chat Command

Main article: Chat
Packet ID State Bound To Field Name Field Type Notes
0x04 Play Server Command String (32767) The command typed by the client.

Signed Chat Command

Main article: Chat
Packet ID State Bound To Field Name Field Type Notes
0x05 Play Server Command String (32767) The command typed by the client.
Timestamp Long The timestamp that the command was executed.
Salt Long The salt for the following argument signatures.
Array length VarInt Number of entries in the following array. The maximum length in Notchian server is 8.
Array of argument signatures Argument name Array (8) String (16) The name of the argument that is signed by the following signature.
Signature Byte Array (256) The signature that verifies the argument. Always 256 bytes and is not length-prefixed.
Message Count VarInt
Acknowledged Fixed BitSet (20)

Chat Message

Main article: Chat

Used to send a chat message to the server. The message may not be longer than 256 characters or else the server will kick the client.

The server will broadcast a Player Chat Message packet with Chat Type minecraft:chat to all players that haven't disabled chat (including the player that sent the message). See Chat#Processing chat for more information.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x06

resource:
chat
Play Server Message String (256)
Timestamp Long
Salt Long The salt used to verify the signature hash.
Has Signature Boolean Whether the next field is present.
Signature Optional Byte Array (256) The signature used to verify the chat message's authentication. When present, always 256 bytes and not length-prefixed.
Message Count VarInt
Acknowledged Fixed BitSet (20)

Player Session

Packet ID State Bound To Field Name Field Type Notes
0x07 Play Server Session Id UUID
Public Key Expires At Long The time the play session key expires in epoch milliseconds.
Public Key Length VarInt Length of the proceeding public key. Maximum length in Notchian server is 512 bytes.
Public Key Byte Array (512) A byte array of an X.509-encoded public key.
Key Signature Length VarInt Length of the proceeding key signature array. Maximum length in Notchian server is 4096 bytes.
Key Signature Byte Array (4096) The signature consists of the player UUID, the key expiration timestamp, and the public key data. These values are hashed using SHA-1 and signed using Mojang's private RSA key.

Chunk Batch Received

Notifies the server that the chunk batch has been received by the client. The server uses the value sent in this packet to adjust the number of chunks to be sent in a batch.

The Notchian server will stop sending further chunk data until the client acknowledges the sent chunk batch. After the first acknowledgement, the server adjusts this number to allow up to 10 unacknowledged batches.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x08

resource:
chunk_batch_received
Play Server Chunks per tick Float Desired chunks per tick.

Client Status

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x09

resource:
client_command
Play Server Action ID VarInt Enum See below

Action ID values:

Action ID Action Notes
0 Perform respawn Sent when the client is ready to complete login and when the client is ready to respawn after death.
1 Request stats Sent when the client opens the Statistics menu.

Client Information (play)

Sent when the player connects, or when settings are changed.

Packet ID State Bound To Field Name Field Type Notes
0x0A Play Server Locale String (16) e.g. en_GB.
View Distance Byte Client-side render distance, in chunks.
Chat Mode VarInt Enum 0: enabled, 1: commands only, 2: hidden. See Chat#Client chat mode for more information.
Chat Colors Boolean “Colors” multiplayer setting. Can the chat be colored?
Displayed Skin Parts Unsigned Byte Bit mask, see below.
Main Hand VarInt Enum 0: Left, 1: Right.
Enable text filtering Boolean Enables filtering of text on signs and written book titles. Currently always false (i.e. the filtering is disabled)
Allow server listings Boolean Servers usually list online players, this option should let you not show up in that list.

Displayed Skin Parts flags:

  • Bit 0 (0x01): Cape enabled
  • Bit 1 (0x02): Jacket enabled
  • Bit 2 (0x04): Left Sleeve enabled
  • Bit 3 (0x08): Right Sleeve enabled
  • Bit 4 (0x10): Left Pants Leg enabled
  • Bit 5 (0x20): Right Pants Leg enabled
  • Bit 6 (0x40): Hat enabled

The most significant bit (bit 7, 0x80) appears to be unused.

Command Suggestions Request

Sent when the client needs to tab-complete a minecraft:ask_server suggestion type.

Packet ID State Bound To Field Name Field Type Notes
0x0B Play Server Transaction Id VarInt The id of the transaction that the server will send back to the client in the response of this packet. Client generates this and increments it each time it sends another tab completion that doesn't get a response.
Text String (32500) All text behind the cursor without the / (e.g. to the left of the cursor in left-to-right languages like English).

Acknowledge Configuration

Sent by the client upon receiving a Start Configuration packet from the server.

Packet ID State Bound To Field Name Field Type Notes
0x0C Play Server no fields

This packet switches the connection state to configuration.

Click Container Button

Used when clicking on window buttons. Until 1.14, this was only used by enchantment tables.

Packet ID State Bound To Field Name Field Type Notes
0x0D Play Server Window ID Byte The ID of the window sent by Open Screen.
Button ID Byte Meaning depends on window type; see below.
Window type ID Meaning
Enchantment Table 0 Topmost enchantment.
1 Middle enchantment.
2 Bottom enchantment.
Lectern 1 Previous page (which does give a redstone output).
2 Next page.
3 Take Book.
100+page Opened page number - 100 + number.
Stonecutter Recipe button number - 4*row + col. Depends on the item.
Loom Recipe button number - 4*row + col. Depends on the item.

Click Container

This packet is sent by the client when the player clicks on a slot in a window.

Packet ID State Bound To Field Name Field Type Notes
0x0E Play Server Window ID Unsigned Byte The ID of the window which was clicked. 0 for player inventory. The server ignores any packets targeting a Window ID other than the current one, including ignoring 0 when any other window is open.
State ID VarInt The last received State ID from either a Set Container Slot or a Set Container Content packet.
Slot Short The clicked slot number, see below.
Button Byte The button used in the click, see below.
Mode VarInt Enum Inventory operation mode, see below.
Length of the array VarInt Maximum value for Notchian server is 128 slots.
Array of changed slots Slot number Array (128) Short
Slot data Slot New data for this slot, in the client's opinion; see below.
Carried item Slot Item carried by the cursor. Has to be empty (item ID = -1) for drop mode, otherwise nothing will happen.

See Inventory for further information about how slots are indexed.

After performing the action, the server compares the results to the slot change information included in the packet, as applied on top of the server's view of the container's state prior to the action. For any slots that do not match, it sends Set Container Slot packets containing the correct results. If State ID does not match the last ID sent by the server, it will instead send a full Set Container Content to resynchronize the client.

When right-clicking on a stack of items, half the stack will be picked up and half left in the slot. If the stack is an odd number, the half left in the slot will be smaller of the amounts.

The distinct type of click performed by the client is determined by the combination of the Mode and Button fields.

Mode Button Slot Trigger
0 0 Normal Left mouse click
1 Normal Right mouse click
0 -999 Left click outside inventory (drop cursor stack)
1 -999 Right click outside inventory (drop cursor single item)
1 0 Normal Shift + left mouse click
1 Normal Shift + right mouse click (identical behavior)
2 0 Normal Number key 1
1 Normal Number key 2
2 Normal Number key 3
8 Normal Number key 9
Button is used as the slot index (impossible in vanilla clients)
40 Normal Offhand swap key F
3 2 Normal Middle click, only defined for creative players in non-player inventories.
4 0 Normal* Drop key (Q) (* Clicked item is always empty)
1 Normal* Control + Drop key (Q) (* Clicked item is always empty)
5 0 -999 Starting left mouse drag
4 -999 Starting right mouse drag
8 -999 Starting middle mouse drag, only defined for creative players in non-player inventories.
1 Normal Add slot for left-mouse drag
5 Normal Add slot for right-mouse drag
9 Normal Add slot for middle-mouse drag, only defined for creative players in non-player inventories.
2 -999 Ending left mouse drag
6 -999 Ending right mouse drag
10 -999 Ending middle mouse drag, only defined for creative players in non-player inventories.
6 0 Normal Double click
1 Normal Pickup all but check items in reverse order (impossible in vanilla clients)

Starting from version 1.5, “painting mode” is available for use in inventory windows. It is done by picking up stack of something (more than 1 item), then holding mouse button (left, right or middle) and dragging held stack over empty (or same type in case of right button) slots. In that case client sends the following to server after mouse button release (omitting first pickup packet which is sent as usual):

  1. packet with mode 5, slot -999, button (0 for left | 4 for right);
  2. packet for every slot painted on, mode is still 5, button (1 | 5);
  3. packet with mode 5, slot -999, button (2 | 6);

If any of the painting packets other than the “progress” ones are sent out of order (for example, a start, some slots, then another start; or a left-click in the middle) the painting status will be reset.

Close Container

This packet is sent by the client when closing a window.

Notchian clients send a Close Window packet with Window ID 0 to close their inventory even though there is never an Open Screen packet for the inventory.

Packet ID State Bound To Field Name Field Type Notes
0x0F Play Server Window ID Unsigned Byte This is the ID of the window that was closed. 0 for player inventory.

Change Container Slot State

This packet is sent by the client when toggling the state of a Crafter.

Packet ID State Bound To Field Name Field Type Notes
0x10 Play Server Slot ID VarInt This is the ID of the slot that was changed.
Window ID VarInt This is the ID of the window that was changed.
State Boolean The new state of the slot. True for enabled, false for disabled.

Cookie Response (play)

Response to a Cookie Request (play) from the server. The Notchian server only accepts responses of up to 5 kiB in size.

Packet ID State Bound To Field Name Field Type Notes
0x11 Play Server Key Identifier The identifier of the cookie.
Has Payload Boolean The payload is only present if the cookie exists on the client.
Payload Length Optional VarInt Length of the following byte array.
Payload Optional Byte Array (5120) The data of the cookie, if any.

Serverbound Plugin Message (play)

Main article: Plugin channels

Mods and plugins can use this to send their data. Minecraft itself uses some plugin channels. These internal channels are in the minecraft namespace.

More documentation on this: https://dinnerbone.com/blog/2012/01/13/minecraft-plugin-channels-messaging/

Note that the length of Data is known only from the packet length, since the packet has no length field of any kind.

Packet ID State Bound To Field Name Field Type Notes
0x12 Play Server Channel Identifier Name of the plugin channel used to send the data.
Data Byte Array (32767) Any data, depending on the channel. minecraft: channels are documented here. The length of this array must be inferred from the packet length.

In Notchian server, the maximum data length is 32767 bytes.

Debug Sample Subscription

Subscribes to the specified type of debug sample data, which is then sent periodically to the client via Debug Sample.

The subscription is retained for 10 seconds (the Notchian server checks that both 10.001 real-time seconds and 201 ticks have elapsed), after which the client is automatically unsubscribed. The Notchian client resends this packet every 5 seconds to keep up the subscription.

The Notchian server only allows subscriptions from players that are server operators.

Packet ID State Bound To Field Name Field Type Notes
0x13 Play Server Sample Type VarInt Enum The type of debug sample to subscribe to. Can be one of the following:
  • 0 - Tick time

Edit Book

Packet ID State Bound To Field Name Field Type Notes
0x14 Play Server Slot VarInt The hotbar slot where the written book is located
Count VarInt Number of elements in the following array. Maximum array size is 200.
Entries Array (200) of String (8192) Text from each page. Maximum string length is 8192 chars.
Has title Boolean If true, the next field is present. true if book is being signed, false if book is being edited.
Title Optional String (128) Title of book.

Query Entity Tag

Used when F3+I is pressed while looking at an entity.

Packet ID State Bound To Field Name Field Type Notes
0x15 Play Server Transaction ID VarInt An incremental ID so that the client can verify that the response matches.
Entity ID VarInt The ID of the entity to query.

Interact

This packet is sent from the client to the server when the client attacks or right-clicks another entity (a player, minecart, etc).

A Notchian server only accepts this packet if the entity being attacked/used is visible without obstruction and within a 4-unit radius of the player's position.

The target X, Y, and Z fields represent the difference between the vector location of the cursor at the time of the packet and the entity's position.

Note that middle-click in creative mode is interpreted by the client and sent as a Set Creative Mode Slot packet instead.

Packet ID State Bound To Field Name Field Type Notes
0x16 Play Server Entity ID VarInt The ID of the entity to interact. Note the special case described below.
Type VarInt Enum 0: interact, 1: attack, 2: interact at.
Target X Optional Float Only if Type is interact at.
Target Y Optional Float Only if Type is interact at.
Target Z Optional Float Only if Type is interact at.
Hand Optional VarInt Enum Only if Type is interact or interact at; 0: main hand, 1: off hand.
Sneaking Boolean If the client is sneaking.

Interaction with the ender dragon is an odd special case characteristic of release deadline–driven design. 8 consecutive entity IDs following the dragon's ID (id + 1, id + 2, ..., id + 8) are reserved for the 8 hitboxes that make up the dragon:

ID offset Description
0 The dragon itself (never used in this packet)
1 Head
2 Neck
3 Body
4 Tail 1
5 Tail 2
6 Tail 3
7 Wing 1
8 Wing 2

Jigsaw Generate

Sent when Generate is pressed on the Jigsaw Block interface.

Packet ID State Bound To Field Name Field Type Notes
0x17 Play Server Location Position Block entity location.
Levels VarInt Value of the levels slider/max depth to generate.
Keep Jigsaws Boolean

Serverbound Keep Alive (play)

The server will frequently send out a keep-alive (see Clientbound Keep Alive), each containing a random ID. The client must respond with the same packet.

Packet ID State Bound To Field Name Field Type Notes
protocol:
0x18

resource:
keep_alive
Play Server Keep Alive ID Long

Lock Difficulty

Must have at least op level 2 to use. Appears to only be used on singleplayer; the difficulty buttons are still disabled in multiplayer.

Packet ID State Bound To Field Name Field Type Notes
0x19 Play Server Locked Boolean

Set Player Position

Updates the player's XYZ position on the server.

If the player is in a vehicle, the position is ignored (but in case of Set Player Position and Rotation, the rotation is still used as normal). No validation steps other than value range clamping are performed in this case.

If the player is sleeping, the position (or rotation) is not changed, and a Synchronize Player Position is sent if the received position deviated from the server's view by more than a meter.

The Notchian server silently clamps the x and z coordinates between -30,000,000 and 30,000,000, and the y coordinate between -20,000,000 and 20,000,000. A similar condition has historically caused a kick for "Illegal position"; this is no longer the case. However, infinite or NaN coordinates (or angles) still result in a kick for multiplayer.disconnect.invalid_player_movement.

As of 1.20.6, checking for moving too fast is achieved like this (sic):

  • Each server tick, the player's current position is stored.
  • When the player moves, the offset from the stored position to the requested position is computed (Δx, Δy, Δz).
  • The requested movement distance squared is computed as Δx² + Δy² + Δz².
  • The baseline expected movement distance squared is computed based on the player's server-side velocity as Vx² + Vy² + Vz². The player's server-side velocity is a somewhat ill-defined quantity that includes among other things gravity, jump velocity and knockback, but not regular horizontal movement. A proper description would bring much of Minecraft's physics engine with it. It is accessible as the Motion NBT tag on the player entity.
  • The maximum permitted movement distance squared is computed as 100 (300 if the player is using an elytra), multiplied by the number of movement packets received since the last tick, including this one, unless that value is greater than 5, in which case no multiplier is applied.
  • If the requested movement distance squared minus the baseline distance squared is more than the maximum squared, the player is moving too fast.

If the player is moving too fast, it is logged that "<player> moved too quickly! " followed by the change in x, y, and z, and the player is teleported back to their current (before this packet) server-side position.

Checking for block collisions is achieved like this:

  • A temporary collision-checked move of the player is attempted from its current position to the requested one.
  • The offset from the resulting position to the requested position is computed. If the absolute value of the offset on the y axis is less than 0.5, it (only the y component) is rounded down to 0.
  • If the magnitude of the offset is greater than 0.25 and the player isn't in creative or spectator mode, it is logged that "<player> moved wrongly!", and the player is teleported back to their current (before this packet) server-side position.
  • In addition, if the player's hitbox stationary at the requested position would intersect with a block, and they aren't in spectator mode, they are teleported back without a log message.

Checking for illegal flight is achieved like this:

  • When a movement packet is received, a flag indicating whether or not the player is floating mid-air is updated. The flag is set if the move test described above detected no collision below the player and the y component of the offset from the player's current position to the requested one is greater than -0.5, unless any of various conditions permitting flight (creative mode, elytra, levitation effect, etc., but not jumping) are met.
  • Each server tick, it is checked if the flag has been set for more than 80 consecutive ticks. If so, and the player isn't currently sleeping, dead or riding a vehicle, they are kicked for multiplayer.disconnect.flying.
Packet ID State Bound To Field Name Field Type Notes
0x1A Play Server X Double Absolute position.
Feet Y Double Absolute feet position, normally Head Y - 1.62.
Z Double Absolute position.
On Ground Boolean True if the client is on the ground, false otherwise.

Set Player Position and Rotation

A combination of Move Player Rotation and Move Player Position.

Packet ID State Bound To Field Name Field Type Notes
0x1B Play Server X Double Absolute position.
Feet Y Double Absolute feet position, normally Head Y - 1.62.
Z Double Absolute position.
Yaw Float Absolute rotation on the X Axis, in degrees.
Pitch Float Absolute rotation on the Y Axis, in degrees.
On Ground Boolean True if the client is on the ground, false otherwise.

Set Player Rotation

The unit circle for yaw
The unit circle of yaw, redrawn

Updates the direction the player is looking in.

Yaw is measured in degrees, and does not follow classical trigonometry rules. The unit circle of yaw on the XZ-plane starts at (0, 1) and turns counterclockwise, with 90 at (-1, 0), 180 at (0,-1) and 270 at (1, 0). Additionally, yaw is not clamped to between 0 and 360 degrees; any number is valid, including negative numbers and numbers greater than 360.

Pitch is measured in degrees, where 0 is looking straight ahead, -90 is looking straight up, and 90 is looking straight down.

The yaw and pitch of player (in degrees), standing at point (x0, y0, z0) and looking towards point (x, y, z) can be calculated with:

dx = x-x0
dy = y-y0
dz = z-z0
r = sqrt( dx*dx + dy*dy + dz*dz )
yaw = -atan2(dx,dz)/PI*180
if yaw < 0 then
    yaw = 360 + yaw
pitch = -arcsin(dy/r)/PI*180

You can get a unit vector from a given yaw/pitch via:

x = -cos(pitch) * sin(yaw)
y = -sin(pitch)
z =  cos(pitch) * cos(yaw)
Packet ID State Bound To Field Name Field Type Notes
0x1C Play Server Yaw Float Absolute rotation on the X Axis, in degrees.
Pitch Float Absolute rotation on the Y Axis, in degrees.
On Ground Boolean True if the client is on the ground, false otherwise.

Set Player On Ground

This packet as well as Set Player Position, Set Player Rotation, and Set Player Position and Rotation are called the “serverbound movement packets”. Vanilla clients will send Move Player Position once every 20 ticks even for a stationary player.

This packet is used to indicate whether the player is on ground (walking/swimming), or airborne (jumping/falling).

When dropping from sufficient height, fall damage is applied when this state goes from false to true. The amount of damage applied is based on the point where it last changed from true to false. Note that there are several movement related packets containing this state.

Packet ID State Bound To Field Name Field Type Notes
0x1D Play Server On Ground Boolean True if the client is on the ground, false otherwise.

Move Vehicle

Sent when a player moves in a vehicle. Fields are the same as in Set Player Position and Rotation. Note that all fields use absolute positioning and do not allow for relative positioning.

Packet ID State Bound To Field Name Field Type Notes
0x1E Play Server X Double Absolute position (X coordinate).
Y Double Absolute position (Y coordinate).
Z Double Absolute position (Z coordinate).
Yaw Float Absolute rotation on the vertical axis, in degrees.
Pitch Float Absolute rotation on the horizontal axis, in degrees.

Paddle Boat

Used to visually update whether boat paddles are turning. The server will update the Boat entity metadata to match the values here.

Packet ID State Bound To Field Name Field Type Notes
0x1F Play Server Left paddle turning Boolean
Right paddle turning Boolean

Right paddle turning is set to true when the left button or forward button is held, left paddle turning is set to true when the right button or forward button is held.

Pick Item

Used to swap out an empty space on the hotbar with the item in the given inventory slot. The Notchian client uses this for pick block functionality (middle click) to retrieve items from the inventory.

Packet ID State Bound To Field Name Field Type Notes
0x20 Play Server Slot to use VarInt See Inventory.

The server first searches the player's hotbar for an empty slot, starting from the current slot and looping around to the slot before it. If there are no empty slots, it starts a second search from the current slot and finds the first slot that does not contain an enchanted item. If there still are no slots that meet that criteria, then the server uses the currently selected slot.

After finding the appropriate slot, the server swaps the items and sends 3 packets:

Ping Request (play)

Packet ID State Bound To Field Name Field Type Notes
0x21 Play Server Payload Long May be any number. Notchian clients use a system-dependent time value which is counted in milliseconds.

Place Recipe

This packet is sent when a player clicks a recipe in the crafting book that is craftable (white border).

Packet ID State Bound To Field Name Field Type Notes
0x22 Play Server Window ID Byte
Recipe Identifier A recipe ID.
Make all Boolean Affects the amount of items processed; true if shift is down when clicked.

Player Abilities (serverbound)

The vanilla client sends this packet when the player starts/stops flying with the Flags parameter changed accordingly.

Packet ID State Bound To Field Name Field Type Notes
0x23 Play Server Flags Byte Bit mask. 0x02: is flying.

Player Action

Sent when the player mines a block. A Notchian server only accepts digging packets with coordinates within a 6-unit radius between the center of the block and the player's eyes.

Packet ID State Bound To Field Name Field Type Notes
0x24 Play Server Status VarInt Enum The action the player is taking against the block (see below).
Location Position Block position.
Face Byte Enum The face being hit (see below).
Sequence VarInt Block change sequence number (see #Acknowledge Block Change).

Status can be one of seven values:

Value Meaning Notes
0 Started digging Sent when the player starts digging a block. If the block was instamined or the player is in creative mode, the client will not send Status = Finished digging, and will assume the server completed the destruction. To detect this, it is necessary to calculate the block destruction speed server-side.
1 Cancelled digging Sent when the player lets go of the Mine Block key (default: left click). Face is always set to -Y.
2 Finished digging Sent when the client thinks it is finished.
3 Drop item stack Triggered by using the Drop Item key (default: Q) with the modifier to drop the entire selected stack (default: Control or Command, depending on OS). Location is always set to 0/0/0, Face is always set to -Y. Sequence is always set to 0.
4 Drop item Triggered by using the Drop Item key (default: Q). Location is always set to 0/0/0, Face is always set to -Y. Sequence is always set to 0.
5 Shoot arrow / finish eating Indicates that the currently held item should have its state updated such as eating food, pulling back bows, using buckets, etc. Location is always set to 0/0/0, Face is always set to -Y. Sequence is always set to 0.
6 Swap item in hand Used to swap or assign an item to the second hand. Location is always set to 0/0/0, Face is always set to -Y. Sequence is always set to 0.

The Face field can be one of the following values, representing the face being hit:

Value Offset Face
0 -Y Bottom
1 +Y Top
2 -Z North
3 +Z South
4 -X West
5 +X East

Player Command

Sent by the client to indicate that it has performed certain actions: sneaking (crouching), sprinting, exiting a bed, jumping with a horse, and opening a horse's inventory while riding it.

Packet ID State Bound To Field Name Field Type Notes
0x25 Play Server Entity ID VarInt Player ID
Action ID VarInt Enum The ID of the action, see below.
Jump Boost VarInt Only used by the “start jump with horse” action, in which case it ranges from 0 to 100. In all other cases it is 0.

Action ID can be one of the following values:

ID Action
0 Start sneaking
1 Stop sneaking
2 Leave bed
3 Start sprinting
4 Stop sprinting
5 Start jump with horse
6 Stop jump with horse
7 Open vehicle inventory
8 Start flying with elytra

Leave bed is only sent when the “Leave Bed” button is clicked on the sleep GUI, not when waking up in the morning.

Open vehicle inventory is only sent when pressing the inventory key (default: E) while on a horse or chest boat — all other methods of opening such an inventory (involving right-clicking or shift-right-clicking it) do not use this packet.

Player Input

Packet ID State Bound To Field Name Field Type Notes
0x26 Play Server Sideways Float Positive to the left of the player.
Forward Float Positive forward.
Flags Unsigned Byte Bit mask. 0x1: jump, 0x2: unmount.

Also known as 'Input' packet.

Pong (play)

Response to the clientbound packet (Ping) with the same id.

Packet ID State Bound To Field Name Field Type Notes
0x27 Play Server ID Int id is the same as the ping packet

Change Recipe Book Settings

Replaces Recipe Book Data, type 1.

Packet ID State Bound To Field Name Field Type Notes
0x28 Play Server Book ID VarInt Enum 0: crafting, 1: furnace, 2: blast furnace, 3: smoker.
Book Open Boolean
Filter Active Boolean

Set Seen Recipe

Sent when recipe is first seen in recipe book. Replaces Recipe Book Data, type 0.

Packet ID State Bound To Field Name Field Type Notes
0x29 Play Server Recipe ID Identifier

Rename Item

Sent as a player is renaming an item in an anvil (each keypress in the anvil UI sends a new Rename Item packet). If the new name is empty, then the item loses its custom name (this is different from setting the custom name to the normal name of the item). The item name may be no longer than 50 characters long, and if it is longer than that, then the rename is silently ignored.

Packet ID State Bound To Field Name Field Type Notes
0x2A Play Server Item name String (32767) The new name of the item.

Resource Pack Response (play)

Packet ID State Bound To Field Name Field Type Notes
0x2B Play Server
UUID UUID The unique identifier of the resource pack received in the Add Resource Pack (play) request.
Result VarInt Enum Result ID (see below).

Result can be one of the following values:


ID Result
0 Successfully downloaded
1 Declined
2 Failed to download
3 Accepted
4 Downloaded
5 Invalid URL
6 Failed to reload
7 Discarded

Seen Advancements

Packet ID State Bound To Field Name Field Type Notes
0x2C Play Server Action VarInt Enum 0: Opened tab, 1: Closed screen.
Tab ID Optional Identifier Only present if action is Opened tab.

Select Trade

When a player selects a specific trade offered by a villager NPC.

Packet ID State Bound To Field Name Field Type Notes
0x2D Play Server Selected slot VarInt The selected slot in the players current (trading) inventory.

Set Beacon Effect

Changes the effect of the current beacon.

Packet ID State Bound To Field Name Field Type Notes
0x2E Play Server
Has Primary Effect Boolean
Primary Effect Optional VarInt A Potion ID.
Has Secondary Effect Boolean
Secondary Effect Optional VarInt A Potion ID.

Set Held Item (serverbound)

Sent when the player changes the slot selection.

Packet ID State Bound To Field Name Field Type Notes
0x2F Play Server Slot Short The slot which the player has selected (0–8).

Program Command Block

Packet ID State Bound To Field Name Field Type Notes
0x30 Play Server
Location Position
Command String (32767)
Mode VarInt Enum One of SEQUENCE (0), AUTO (1), or REDSTONE (2).
Flags Byte 0x01: Track Output (if false, the output of the previous command will not be stored within the command block); 0x02: Is conditional; 0x04: Automatic.

Program Command Block Minecart

Packet ID State Bound To Field Name Field Type Notes
0x31 Play Server Entity ID VarInt
Command String (32767)
Track Output Boolean If false, the output of the previous command will not be stored within the command block.

Set Creative Mode Slot

While the user is in the standard inventory (i.e., not a crafting bench) in Creative mode, the player will send this packet.

Clicking in the creative inventory menu is quite different from non-creative inventory management. Picking up an item with the mouse actually deletes the item from the server, and placing an item into a slot or dropping it out of the inventory actually tells the server to create the item from scratch. (This can be verified by clicking an item that you don't mind deleting, then severing the connection to the server; the item will be nowhere to be found when you log back in.) As a result of this implementation strategy, the "Destroy Item" slot is just a client-side implementation detail that means "I don't intend to recreate this item.". Additionally, the long listings of items (by category, etc.) are a client-side interface for choosing which item to create. Picking up an item from such listings sends no packets to the server; only when you put it somewhere does it tell the server to create the item in that location.

This action can be described as "set inventory slot". Picking up an item sets the slot to item ID -1. Placing an item into an inventory slot sets the slot to the specified item. Dropping an item (by clicking outside the window) effectively sets slot -1 to the specified item, which causes the server to spawn the item entity, etc.. All other inventory slots are numbered the same as the non-creative inventory (including slots for the 2x2 crafting menu, even though they aren't visible in the vanilla client).

Packet ID State Bound To Field Name Field Type Notes
0x32 Play Server Slot Short Inventory slot.
Clicked Item Slot

Program Jigsaw Block

Sent when Done is pressed on the Jigsaw Block interface.

Packet ID State Bound To Field Name Field Type Notes
0x33 Play Server Location Position Block entity location
Name Identifier
Target Identifier
Pool Identifier
Final state String (32767) "Turns into" on the GUI, final_state in NBT.
Joint type String (32767) rollable if the attached piece can be rotated, else aligned.
Selection priority VarInt
Placement priority VarInt

Program Structure Block

Packet ID State Bound To Field Name Field Type Notes
0x34 Play Server
Location Position Block entity location.
Action VarInt Enum An additional action to perform beyond simply saving the given data; see below.
Mode VarInt Enum One of SAVE (0), LOAD (1), CORNER (2), DATA (3).
Name String (32767)
Offset X Byte Between -48 and 48.
Offset Y Byte Between -48 and 48.
Offset Z Byte Between -48 and 48.
Size X Byte Between 0 and 48.
Size Y Byte Between 0 and 48.
Size Z Byte Between 0 and 48.
Mirror VarInt Enum One of NONE (0), LEFT_RIGHT (1), FRONT_BACK (2).
Rotation VarInt Enum One of NONE (0), CLOCKWISE_90 (1), CLOCKWISE_180 (2), COUNTERCLOCKWISE_90 (3).
Metadata String (128)
Integrity Float Between 0 and 1.
Seed VarLong
Flags Byte 0x01: Ignore entities; 0x02: Show air; 0x04: Show bounding box.

Possible actions:

  • 0 - Update data
  • 1 - Save the structure
  • 2 - Load the structure
  • 3 - Detect size

The Notchian client uses update data to indicate no special action should be taken (i.e. the done button).

Update Sign

This message is sent from the client to the server when the “Done” button is pushed after placing a sign.

The server only accepts this packet after Open Sign Editor, otherwise this packet is silently ignored.

Packet ID State Bound To Field Name Field Type Notes
0x35 Play Server Location Position Block Coordinates.
Is Front Text Boolean Whether the updated text is in front or on the back of the sign
Line 1 String (384) First line of text in the sign.
Line 2 String (384) Second line of text in the sign.
Line 3 String (384) Third line of text in the sign.
Line 4 String (384) Fourth line of text in the sign.

Swing Arm

Sent when the player's arm swings.

Packet ID State Bound To Field Name Field Type Notes
0x36 Play Server Hand VarInt Enum Hand used for the animation. 0: main hand, 1: off hand.

Teleport To Entity

Teleports the player to the given entity. The player must be in spectator mode.

The Notchian client only uses this to teleport to players, but it appears to accept any type of entity. The entity does not need to be in the same dimension as the player; if necessary, the player will be respawned in the right world. If the given entity cannot be found (or isn't loaded), this packet will be ignored. It will also be ignored if the player attempts to teleport to themselves.

Packet ID State Bound To Field Name Field Type Notes
0x37 Play Server Target Player UUID UUID of the player to teleport to (can also be an entity UUID).

Use Item On

Packet ID State Bound To Field Name Field Type Notes
0x38 Play Server Hand VarInt Enum The hand from which the block is placed; 0: main hand, 1: off hand.
Location Position Block position.
Face VarInt Enum The face on which the block is placed (as documented at Player Action).
Cursor Position X Float The position of the crosshair on the block, from 0 to 1 increasing from west to east.
Cursor Position Y Float The position of the crosshair on the block, from 0 to 1 increasing from bottom to top.
Cursor Position Z Float The position of the crosshair on the block, from 0 to 1 increasing from north to south.
Inside block Boolean True when the player's head is inside of a block.
Sequence VarInt Block change sequence number (see #Acknowledge Block Change).

Upon placing a block, this packet is sent once.

The Cursor Position X/Y/Z fields (also known as in-block coordinates) are calculated using raytracing. The unit corresponds to sixteen pixels in the default resource pack. For example, let's say a slab is being placed against the south face of a full block. The Cursor Position X will be higher if the player was pointing near the right (east) edge of the face, lower if pointing near the left. The Cursor Position Y will be used to determine whether it will appear as a bottom slab (values 0.0–0.5) or as a top slab (values 0.5-1.0). The Cursor Position Z should be 1.0 since the player was looking at the southernmost part of the block.

Inside block is true when a player's head (specifically eyes) are inside of a block's collision. In 1.13 and later versions, collision is rather complicated and individual blocks can have multiple collision boxes. For instance, a ring of vines has a non-colliding hole in the middle. This value is only true when the player is directly in the box. In practice, though, this value is only used by scaffolding to place in front of the player when sneaking inside of it (other blocks will place behind when you intersect with them -- try with glass for instance).

Use Item

Sent when pressing the Use Item key (default: right click) with an item in hand.

Packet ID State Bound To Field Name Field Type Notes
0x39 Play Server Hand VarInt Enum Hand used for the animation. 0: main hand, 1: off hand.
Sequence VarInt Block change sequence number (see #Acknowledge Block Change).
Yaw Float Player head rotation along the Y-Axis.
Pitch Float Player head rotation along the X-Axis.