Registry Data

Registries are repositories of data that contain entries pertaining to certain aspects of the game, such as the world, the player, among others.

The ability for the server to send customized registries to the client was introduced in 1.16.3, which allows for a great deal of customization over certain features of the game.

Format

The server sends these registries to the client via Registry Data packet during the configuration phase.

Packet ID	State	Bound To	Field Name	Field Type	Notes
0x05	Configuration	Client	Registry Data	NBT Tag Compound	Information included below.

The Registry Data field represents a list of all available registries in the form of a Compound Tag. Elements in this compound are defined by the registry information, associated with the registry's name, as shown in the example below:

{
    "minecraft:worldgen/biome": {
        "type": "minecraft:worldgen/biome",
        "value": [
            {
                "name": "minecraft:ocean",
                "id": 0,
                "element": { /* Element */ }
            },
            {
                "name": "minecraft:plains",
                "id": 1,
                "element": { /* Element */ }
            },
            { /* Registry Entry */ }
            ...
        ]
    },
    "minecraft:dimension_type": { /* Registry */ },
    "minecraft:chat_type": { /* Registry */ },
    ...
}

Registry

The Registry Compound Tag specifies the type of the registry, and a list of registry entries.

The name of the registry in the Registry Data is always the same to the registry type in the Notchian implementation.

Name	Type	Notes
type	TAG_String	The type of the registry.
value	TAG_List of TAG_Compound	List of registry entries. The format of the entries is defined by the value of the previous field.

Registry Entry

The Registry Entry Compound Tag specifies a single entry of a Registry.

Name	Type	Notes
name	TAG_String	The name of the entry.
id	TAG_Int	The protocol ID of the entry.
element	TAG_Compound	The actual data of the entry. This field is context-dependent and is based on the type field of its Registry.

Available Registries

The current release specification allows for six different registries to be sent to the client, six of which are required. A brief explanation of each of them is presented below, along with the format of their entries' element field.

Fields marked in __ blue represent data for server-side exclusive operations, and thus have no visible impact on the client.

Armor Trim Material

The minecraft:trim_material registry. It defines various visual properties of trim materials in armors.

Name			Type		Meaning		Values
asset_name			TAG_String		The trim color model to be rendered on top of the armor. The Notchian client uses the corresponding asset located at trims/color_palettes.		Example: "minecraft:amethyst".
ingredient			TAG_String		The ingredient used. This has the visual effect of showing the trimmed armor model on the Smithing Table when the correct item is placed.		Example: "minecraft:copper_ingot".
item_model_index			TAG_Float		Color index of the trim on the armor item when in the inventory.		Default values vary between 0.1 and 1.0.
override_armor_materials			Optional TAG_Compound		Asset for different types of armor materials, which overrides the value specified in the asset_name field. The Notchian client uses this to give a darker color shade when a trim material is applied to armor of the same material, such as iron applied to iron armor.		The key can be either: leather chainmail iron gold diamond turtle netherite The value is the same as asset_name.
description			TAG_Compound or TAG_String		The name of the trim material to be displayed on the armor tool-tip. Any styling used in this component is also applied to the trim pattern description.		See Chat.

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Armor Trim Pattern

The minecraft:trim_pattern registry. It defines various visual properties of trim patterns in armors.

	The following information needs to be added to this page:
	The decal field seems to exist to prevent overlapping between the armor model and the trim model. What exact effect does it have?

Name			Type		Meaning		Values
asset_id			TAG_String		The trim pattern model to be rendered on top of the armor. The Notchian client uses the corresponding asset located at trims/models/armor.		Example: "minecraft:coast".
template_item			TAG_String		The template item used for this trim. This has the visual effect of showing the trimmed armor model on the Smithing Table when the correct item is placed.		Example: "minecraft:coast_armor_trim_smithing_template".
description			TAG_Compound or TAG_String		The name of the trim pattern to be displayed on the armor tool-tip.		See Chat.
decal			TAG_Byte		Whether this trim is a decal.		1: true, 0: false.

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Biome

The minecraft:worldgen/biome registry. It defines several aesthetic characteristics of the biomes present in the game.

Biome entries are referenced in the Chunk Biomes and Chunk Data and Update Light packets.

A registry entry for each biome implemented in the client must exist in the Biome registry, otherwise the client will crash with an exception due to the missing biome.

Name			Type		Meaning		Values
has_precipitation			TAG_Byte		Determines whether or not the biome has precipitation.		1: true, 0: false.
temperature			TAG_Float		The temperature factor of the biome. Affects foliage and grass color if they are not explicitly set.		The default values vary between -0.5 and 2.0.
temperature_modifier			Optional TAG_String		Modifier that affects the resulting temperature.		Can be either: none, for a static temperature throughout the biome (aside from variations depending on the height). frozen, for pockets of warm temperature (0.2) to be randomly distributed throughout the biome. This is used on frozen ocean variants in the Notchian client to simulate spots of unfrozen water, where it always rains instead of snowing.
downfall			TAG_Float		The downfall factor of the biome. Affects foliage and grass color if they are not explicitly set.		The default values vary between 0.0 and 1.0.
effects			TAG_Compound		Biome special effects.		See Effects.

Effects

Name			Type		Meaning		Values
fog_color			TAG_Int		The color of the fog effect when looking past the view distance.		Example: 8364543, which is #7FA1FF in RGB.
water_color			TAG_Int		The tint color of the water blocks.		Example: 8364543, which is #7FA1FF in RGB.
water_fog_color			TAG_Int		The color of the fog effect when looking past the view distance when underwater.		Example: 8364543, which is #7FA1FF in RGB.
sky_color			TAG_Int		The color of the sky.		Example: 8364543, which is #7FA1FF in RGB.
foliage_color			Optional TAG_Int		The tint color of leaves. If not specified, the foliage color is calculated based on biome temperature and downfall.		Example: 8364543, which is #7FA1FF in RGB.
grass_color			Optional TAG_Int		The tint color of the grass. If not specified, the grass color is calculated based on biome temperature and downfall.		Example: 8364543, which is #7FA1FF in RGB.
grass_color_modifier			Optional TAG_String		Modifier that affects the resulting grass color.		Can be either: none, for a static grass color throughout the biome. dark_forest, for a darker, and less saturated shade of the color. swamp, for overriding it with two fixed colors (#4C763C and #6A7039), randomly distributed throughout the biome.
particle			Optional TAG_Compound		Ambient visual particles.		See Particle.
ambient_sound			Optional TAG_String or TAG_Compound		Ambient soundtrack that starts playing when entering the biome, and fades out when exiting it.		Can be either: as a TAG_String: the ID of a soundtrack, such as "minecraft:ambient.basalt_deltas.loop". as a TAG_Compound: see Ambient sound.
mood_sound			Optional TAG_Compound		Additional ambient sound that plays in moody situations. Moodiness increases when blocks around the player are at both sky and block light level zero, and decreases otherwise. The moodiness calculation happens once per tick, and after reaching a certain value, the ambient mood sound is played.		See Mood sound.
additions_sound			Optional TAG_Compound		Additional ambient sound that has a chance of playing randomly every tick.		See Additions sound.
music			Optional TAG_Compound		Music properties for the biome.		See Music.

Particle

Name			Type		Meaning		Values
options			TAG_Compound		Particle type and related options.		See Particle options.
probability			TAG_Float		The chance for the particle to be spawned. Ambient particles are attempted to be spawned multiple times every tick.		The default values vary between 0.0 and 1.0.

Particle options

	The following information needs to be added to this page:
	The extra data specified in the Particle definitions is missing information to allow the particle to be successfully serialized as NBT. Is it here the best place to define them, or somewhere else?

Name			Type		Meaning		Values
type			TAG_String		The name of the particle.		See protocol particle data.
value			Optional Varies		Any necessary extra data to fully define the particle.		See protocol particle data.

Ambient sound

Name			Type		Meaning		Values
sound_id			TAG_String		The ID of a soundtrack		Example: "minecraft:ambient.basalt_deltas.loop"
range			Optional TAG_Float		The range of the sound. If not specified, the volume is used to calculate the effective range.

Mood sound

Name			Type		Meaning		Values
sound			TAG_String		The ID of a soundtrack.		Example: "minecraft:ambient.basalt_deltas.mood"
tick_delay			TAG_Int		Defines the rate at which the moodiness increase, and also the minimum time between plays.		The default value is always 6000.
block_search_extent			TAG_Int		The radius used for the block search around the player during moodiness calculation.		The default value is always 8.
offset			TAG_Double		The distance offset from the player when playing the sound. The sound plays in the direction of the selected block during moodiness calculation, and is magnified by the offset.		The default value is always 2.0.

Additions sound

Name			Type		Meaning		Values
sound			TAG_String		The ID of a soundtrack.		Example: "minecraft:ambient.basalt_deltas.additions"
tick_chance			TAG_Double		The chance of the sound playing during the tick.		The default value is always 0.0111.

Music

Name			Type		Meaning		Values
sound			TAG_String		The ID of a soundtrack.		Example: "minecraft:music.nether.basalt_deltas"
min_delay			TAG_Int		The minimum time in ticks since the last music finished for this music to be able to play.		The default value is always 12000.
max_delay			TAG_Int		The maximum time in ticks since the last music finished for this music to be able to play.		The default value is always 24000.
replace_current_music			TAG_Byte		Whether this music can replace the current one.		1: true, 0: false.

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Chat Type

The minecraft:chat_type registry. It defines the different types of in-game chat and how they're formatted.

Chat type entries are referenced in the Disguised Chat Message and Player Chat Message packets.

Name			Type		Meaning		Values
chat			TAG_Compound		The chat decoration.		See Decoration.
narration			TAG_Compound		The narration decoration.		See Decoration.

Decoration

Name			Type		Meaning		Values
translation_key			TAG_String		The translation key representing the chat format. It can also be a formatting string directly.		Example: "chat.type.text", which translates to "<%s> %s".
style			Optional TAG_Compound		Optional styling to be applied on the final message. Not present in the narration decoration.		See Chat styling.
parameters			TAG_List of TAG_String		Placeholders used when formatting the string given by the translation_key field.		Can be either: sender, for the name of the player sending the message. target, for the name of the player receiving the message, which may be empty. contant, for the actual message.

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Damage Type

The minecraft:damage_type registry. It defines the different types of damage an entity can sustain.

Damage type entries are referenced in the Damage Event packet.

Name	Type	Meaning	Values
message_id	TAG_String	Id of the death message. The full message is displayed as death.attack.<message_id>.	Example: "onFire".
scaling	TAG_String	Whether the damage taken scales with the difficulty.	Can be either: never when_caused_by_living_non_player always
exhaustion	TAG_Float	The amount of exhaustion caused when suffering this type of damage.	Default values are either 0.0 or 0.1.
effects	Optional TAG_String	Effect played when the player suffers this damage, including the sound that is played.	Can be either: hurt thorns drowning burning poking freezing
death_message_type	Optional TAG_String	Defines how the death message is constructed.	Can be either: default, for the message to be built normally. fall_variants, for the most significant fall damage to be considered. intentional_game_design, for MCPE-28723 to be considered as an argument when translating the message.

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Dimension Type

The minecraft:dimension_type registry. It defines the types of dimension that can be attributed to a world, along with all their characteristics.

Dimension type entries are referenced in the Login (play) and Respawn packets.

Name	Type	Meaning	Values
fixed_time	Optional TAG_Long	If set, the time of the day fixed to the specified value.	Allowed values vary between 0 and 24000.
has_skylight	TAG_Byte	Whether the dimension has skylight access or not.	1: true, 0: false.
has_ceiling	TAG_Byte	Whether the dimension has a bedrock ceiling or not. When true, causes lava to spread faster.	1: true, 0: false.
ultrawarm	TAG_Byte	Whether the dimensions behaves like the nether (water evaporates and sponges dry) or not. Also causes lava to spread thinner.	1: true, 0: false.
natural	TAG_Byte	When false, compasses spin randomly. When true, nether portals can spawn zombified piglins.	1: true, 0: false.
coordinate_scale	TAG_Double	The multiplier applied to coordinates when traveling to the dimension.	Allowed values vary between 1e-5 (0.00001) and 3e7 (30000000).
bed_works	TAG_Byte	Whether players can use a bed to sleep.	1: true, 0: false.
respawn_anchor_works	TAG_Byte	Whether players can charge and use respawn anchors.	1: true, 0: false.
min_y	TAG_Int	The minimum Y level.	Allowed values vary between -2032 and 2031, and must also be a multiple of 16. min_y + height cannot exceed 2032.
height	TAG_Int	The maximum height.	Allowed values vary between 16 and 4064, and must also be a multiple of 16. min_y + height cannot exceed 2032.
logical_height	TAG_Int	The maximum height to which chorus fruits and nether portals can bring players within this dimension. (Must be lower than height)	Allowed values vary between 0 and 4064, and must also be a multiple of 16. logical_height cannot exceed the height.
infiniburn	TAG_String	A resource location defining what block tag to use for infiniburn.	"#" or minecraft resource "#minecraft:...".
effects	TAG_String	Defines special dimensional effects, which includes: Cloud level: Height at which clouds appear, if at all. Sky type: Whether it's the normal sky with sun and moon; the low-visibility, foggy sky of the nether; or the static sky of the end. Forced light map: Whether a bright light map is forced, siimilar to the night vision effect. Constant ambient light: Whether blocks have shade on their faces.	Can be either: minecraft:overworld, for clouds at 192, normal sky type, normal light map and normal ambient light. minecraft:the_nether, for no clouds, nether sky type, normal light map and constant ambient light. minecraft:the_end, for no clouds, end sky type, forced light map and normal ambient light.
ambient_light	TAG_Float	How much light the dimension has. Used as interpolation factor when calculating the brightness generated from sky light.	The default values are 0.0 and 0.1, 0.1 for the nether and 0.0 for the other dimensions.
piglin_safe	TAG_Byte	Whether piglins shake and transform to zombified piglins.	1: true, 0: false.
has_raids	TAG_Byte	Whether players with the Bad Omen effect can cause a raid.	1: true, 0: false.
monster_spawn_light_level	TAG_Int or TAG_Compound	During a monster spawn attempt, this is the maximum allowed light level for it to succeed. It can be either a fixed value, or one of several types of distributions.	Can be either: as a TAG_Int: Allowed values vary between 0 and 15. as a TAG_Compound: See Integer distribution.
monster_spawn_block_light_limit	TAG_Int	Maximum allowed block light level monster spawn attempts to happen.	Allowed values vary between 0 and 15. The default values are 0 and 15, 15 for the nether (where monsters can spawn anywhere) and 0 for other dimensions (where monsters can only spawn naturally in complete darkness).

Integer distribution

Integer providers can be either declared as constants with a TAG_Int, or in a structured TAG_Compounds for specific distribution types. For the latter, the following format is used.

	The following information needs to be added to this page:
	The use for integer distributions described in the previous section pertains to monster spawning mechanisms, which is server-sided operation. The values received in the monster_spawn_light_level field have no noticeable impact on the client whatsoever. Should they even be described here?

Name	Type	Meaning	Values
type	TAG_String	The type of distribution.	Can be either: minecraft:constant, for constant values, similarly to when declared as a TAG_Int. minectaft:uniform, for uniformly distributed values between the specified range. minecraft:biased_to_bottom, for values biased towards the lower end, between the specified range. minecraft:clamped, for uniformly distributed values, clamped inside a range. minecraft:weighted_list, for a weighted list of multiple distributions. minecraft:clamped_normal, for normally distributed values, clamped inside a range.
value	TAG_Compound	Extra data pertaining to the type of distribution.	Depends on the type of distribution.

Default Registries

The default registries in the JSON format is available for the following versions:

• 1.20.1
• 1.19.2
• 1.19