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.

Overview

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
Varies	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.

The structure of the entries' data depends on the registry specified in the packet. The structure for each available registry is defined below.

Throughout the configuration phase, the server will send multiple Registry Data packets, each one pertaining to a different registry.

Client/Server Exchange

In order to save bandwidth, the server omits the data for entries pertaining to a data pack that is mutually supported by both the client and server. The exchange is as follows:

1. S→C: Clientbound Known Packs
2. C→S: Serverbound Known Packs
3. Server computes the mutually supported data packs
4. S→C: Multiple Registry Data (excluding mutually supported data)

The ordering in which the entries of a registry are sent defines the numeric ID that they will be assigned to. It is essential to maintain consistency between server and client, since many parts of the protocol reference these entries by their ID. The client will disconnect upon receiving a reference to a non-existing entry.

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			String Tag		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			String Tag		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			Float Tag		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 Compound Tag		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 accepts the same values as asset_name.
description			Compound Tag or String Tag		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 Text formatting.

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			String Tag		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			String Tag		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			Compound Tag or String Tag		The name of the trim pattern to be displayed on the armor tool-tip.		See Text formatting.
decal			Byte Tag		Whether this trim is a decal.		1: true, 0: false.

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.

Name			Type		Meaning		Values
has_precipitation			Byte Tag		Determines whether or not the biome has precipitation.		1: true, 0: false.
temperature			Float Tag		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 String Tag		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			Float Tag		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			Compound Tag		Biome special effects.		See Effects.

Effects

Name			Type		Meaning		Values
fog_color			Int Tag		The color of the fog effect when looking past the view distance.		Example: 8364543, which is #7FA1FF in RGB.
water_color			Int Tag		The tint color of the water blocks.		Example: 8364543, which is #7FA1FF in RGB.
water_fog_color			Int Tag		The color of the fog effect when looking past the view distance when underwater.		Example: 8364543, which is #7FA1FF in RGB.
sky_color			Int Tag		The color of the sky.		Example: 8364543, which is #7FA1FF in RGB.
foliage_color			Optional Int Tag		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 Int Tag		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 String Tag		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 Compound Tag		Ambient visual particles.		See Particle.
ambient_sound			Optional String Tag or Compound Tag		Ambient soundtrack that starts playing when entering the biome, and fades out when exiting it.		Can be either: as a String Tag: the ID of a soundtrack, such as "minecraft:ambient.basalt_deltas.loop". as a Compound Tag: see Ambient sound.
mood_sound			Optional Compound Tag		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 Compound Tag		Additional ambient sound that has a chance of playing randomly every tick.		See Additions sound.
music			Optional Compound Tag		Music properties for the biome.		See Music.

Particle

Name			Type		Meaning		Values
options			Compound Tag		Particle type and related options.		See Particle options.
probability			Float Tag		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			String Tag		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			String Tag		The ID of a soundtrack		Example: "minecraft:ambient.basalt_deltas.loop"
range			Optional Float Tag		The range of the sound. If not specified, the volume is used to calculate the effective range.

Mood sound

Name			Type		Meaning		Values
sound			String Tag		The ID of a soundtrack.		Example: "minecraft:ambient.basalt_deltas.mood"
tick_delay			Int Tag		Defines the rate at which the moodiness increase, and also the minimum time between plays.		The default value is always 6000.
block_search_extent			Int Tag		The radius used for the block search around the player during moodiness calculation.		The default value is always 8.
offset			Double Tag		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			String Tag		The ID of a soundtrack.		Example: "minecraft:ambient.basalt_deltas.additions"
tick_chance			Double Tag		The chance of the sound playing during the tick.		The default value is always 0.0111.

Music

Name			Type		Meaning		Values
sound			String Tag		The ID of a soundtrack.		Example: "minecraft:music.nether.basalt_deltas"
min_delay			Int Tag		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			Int Tag		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			Byte Tag		Whether this music can replace the current one.		1: true, 0: false.

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			Compound Tag		The chat decoration.		See Decoration.
narration			Compound Tag		The narration decoration.		See Decoration.

Decoration

Name			Type		Meaning		Values
translation_key			String Tag		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 Compound Tag		Optional styling to be applied on the final message. Not present in the narration decoration.		See Text formatting#Styling fields.
parameters			List Tag of String Tag		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. content, for the actual message.

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	String Tag	Id of the death message. The full message is displayed as death.attack.<message_id>.	Example: "onFire".
scaling	String Tag	Whether the damage taken scales with the difficulty.	Can be either: never when_caused_by_living_non_player always
exhaustion	Float Tag	The amount of exhaustion caused when suffering this type of damage.	Default values are either 0.0 or 0.1.
effects	Optional String Tag	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 String Tag	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.

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 Long Tag	If set, the time of the day fixed to the specified value.	Allowed values vary between 0 and 24000.
has_skylight	Byte Tag	Whether the dimension has skylight access or not.	1: true, 0: false.
has_ceiling	Byte Tag	Whether the dimension has a bedrock ceiling or not. When true, causes lava to spread faster.	1: true, 0: false.
ultrawarm	Byte Tag	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	Byte Tag	When false, compasses spin randomly. When true, nether portals can spawn zombified piglins.	1: true, 0: false.
coordinate_scale	Double Tag	The multiplier applied to coordinates when traveling to the dimension.	Allowed values vary between 1e-5 (0.00001) and 3e7 (30000000).
bed_works	Byte Tag	Whether players can use a bed to sleep.	1: true, 0: false.
respawn_anchor_works	Byte Tag	Whether players can charge and use respawn anchors.	1: true, 0: false.
min_y	Int Tag	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	Int Tag	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	Int Tag	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	String Tag	A resource location defining what block tag to use for infiniburn.	"#" or minecraft resource "#minecraft:...".
effects	String Tag	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	Float Tag	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	Byte Tag	Whether piglins shake and transform to zombified piglins.	1: true, 0: false.
has_raids	Byte Tag	Whether players with the Bad Omen effect can cause a raid.	1: true, 0: false.
monster_spawn_light_level	Int Tag or Compound Tag	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 Int Tag: Allowed values vary between 0 and 15. as a Compound Tag: See here.
monster_spawn_block_light_limit	Int Tag	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).

Default Registries

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

• 1.20.6
• 1.20.2
• 1.20.1
• 1.19.2
• 1.19