User:WinX64/Slot Data

The Slot data structure defines how an item is represented when inside an inventory window of any kind, such as a chest or furnace.

This page presents the new Slot data structure, using structured components. You can find the documentation of the old structure, that utilizes raw NBT data, here.

Format

Some description does here.

Name		Type		Meaning
Item Count		VarInt		The item count. Every following field is only present if this value is greater than zero.
Item ID		Optional VarInt		The item ID. Item IDs are distinct from block IDs; see Data Generators for more information.
Number of components to add		Optional VarInt		Number of elements present in the first data component array
Number of components to remove		Optional VarInt		Number of elements present in the second data component array. This serve as a way to remove the default component values that are present on some items.
Components to add	Component type	Optional Array	Optional VarInt Enum	The type of component. See Structured components for more detail.
	Component data		Optional Varies	The component-dependent data. See Structured components for more detail.
Components to remove	Component type	Optional Array	Optional VarInt Enum	The type of component. See Structured components for more detail.

Structured components

The complete list of available components is described below. Items marked in blue cause no noticeable impact on the client, and mainly concern server-side operations.

For a more in-depth description, and information on how the items below are encoded with the NBT format, check here.

Type	Name	Description	Data
0	minecraft:custom_data	Customizable data that doesn't fit any specific component.	As follows: Name Type Description Data NBT Always a Compound Tag.
1	minecraft:max_stack_size	Maximum stack size for the item.	As follows: Name Type Description Max Stack Size VarInt Ranges from 1 to 99.
2	minecraft:max_damage	The maximum damage the item can take before breaking.	As follows: Name Type Description Max Damage VarInt
3	minecraft:damage	The current damage of the item.	As follows: Name Type Description Damage VarInt
4	minecraft:unbreakable	Marks the item as unbrekable.	As follows: Name Type Description Show In Tooltip Boolean Whether the Unbreakable indicator should be shown on the item's tooltip.
5	minecraft:custom_name	Item's custom name. Normally shown in italic, and changeable at an anvil.	As follows: Name Type Description Name Text Component
6	minecraft:item_name	Override for the item's default name. Shown when the item has no custom name.	As follows: Name Type Description Name Text Component
7	minecraft:lore	Item's lore.	As follows: Name Type Description Number of Lines VarInt Number of elements in the following array. Lines Array of Text Component
8	minecraft:rarity	Item's rarity. This affects the default color of the item's name.	As follows: Name Type Description Rarity VarInt Enum Can be one of the following: 0 - Common (white) 1 - Uncommon (yellow) 2 - Rare (aqua) 3 - Epic (pink)
9	minecraft:enchantments	The enchantments of the item.	As follows: Name Type Description Number Of Enchantments VarInt Number of elements in the following array. Enchantment Type ID Array VarInt Enum The ID of the enchantment in the enchantment registry. Level VarInt The level of the enchantment. Show In Tooltip Boolean Whether the list of enchantments should be shown on the item's tooltip.
10	minecraft:can_place_on	List of blocks this block can be placed on when in adventure mode.	As follows: Name Type Description Number Of Predicates VarInt Number of elements in the following array. Block Predicates Array of Block Predicate See Block Predicate. Show In Tooltip Boolean Whether the Unbreakable indicator should be shown on the item's tooltip.
11	minecraft:can_break	List of blocks this item can break when in adventure mode.	As follows: Name Type Description Number Of Predicates VarInt Number of elements in the following array. Block Predicates Array of Block Predicate See Block Predicate. Show In Tooltip Boolean Whether the Unbreakable indicator should be shown on the item's tooltip.
12	minecraft:attribute_modifiers	The attribute modifiers of the item.	As follows: Name Type Description Number Of Attributes VarInt Number of elements in the following array. Attribute Type ID Array VarInt Enum The ID of the attribute. Unique ID UUID The attribute's unique ID. Name String The attribute's name. Value Double The attribute's value. Operation VarInt Enum The operation to be applied upon the value. Can be one of the following: 0 - Add 1 - Multiply base 2 - Multiply total Slot VarInt Enum The item slot placement required for the attribute to have effect. Can be one of the following: 0 - Any 1 - Main hand 2 - Off hand 3 - Hand 4 - Feet 5 - Legs 6 - Chest 7 - Head 8 - Armor 9 - Body Show In Tooltip Boolean Whether the list of attributes should be shown on the item's tooltip.
13	minecraft:custom_model_data	Value for the item predicate when using custom item models. More info can be found here.	As follows: Name Type Description Value VarInt
14	minecraft:hide_additional_tooltip	The following information needs to be added to this page: What is considered as "additional"? What exact items does this hide?	None.
15	minecraft:hide_tooltip	Hides the item's tooltip altogether.	None.
16	minecraft:repair_cost	Accumulated anvil usage cost. The client displays "Too Expensive" if the value is greater than 40 and the player is not in creative mode (more specifically, if they don't have the insta-build flag enabled). This behavior can be overridden by setting the level with the Set Container Property packet.	As follows: Name Type Description Cost VarInt
17	minecraft:creative_slot_lock	Marks the item as non-interactive on the creative inventory (the first 5 rows of items). This is used internally by the client on the paper icon in the saved hot-bars tab.	None.
18	minecraft:enchantment_glint_override	Overrides the item glint resulted from enchantments	As follows: Name Type Description Has Glint VarInt
19	minecraft:intangible_projectile	Marks the projectile as intangible (cannot be picked-up). The Notchian client utilizes the codec meant for chat parsing (and NBT in general) when handling this component, even though it contains no data. This causes an empty Compound Tag to be written, which is likely an unintended bug.	As follows: Name Type Description Value NBT Always a Compound Tag, and always empty.
20	minecraft:food	Makes the item consumable.	As follows: Name Type Description Nutrition VarInt Non-negative Saturation Boolean Can Always Eat Boolean Whether the item can always be eaten, even at full hunger. Seconds To Eat Float How long it takes to consume the item. Number of effects VarInt Number of elements in the following array. Effect Type ID Array Potion Effect The potion effect. See Potion Effect. Probability Float The probability for this effect to be chosen.
21	minecraft:fire_resistant	Marks this item as fire resistant. The client won't render the item as being on-fire if this component is present.	None.
22	minecraft:tool	Alters the speed at which this item breaks certain blocks	As follows: Name Type Description Number of Rules VarInt The number of elements in the following array. Rule Blocks Array Block Set The block this rule applies to. See Block Set. Has Speed Boolean Speed Optional Float The speed at which the tool breaks this rules' blocks. Only present if Has Speed is true. Has Correct Drop For Blocks Boolean Correct Drop For Blocks Optional Boolean Whether items should drop only if this is the correct tool. Only present if Has Correct Drop For Blocks is true. Default Mining Speed Float The mining speed in case none of the previous rule were matched. Damage Per Block VarInt The amount of damage the item takes per block break.
23	minecraft:stored_enchantments	The enchantments stored in this enchanted book.	As follows: Name Type Description Number of enchantments VarInt Number of elements in the following array. Enchantment Type ID Array VarInt Enum The ID of the enchantment in the enchantment registry. Level VarInt The level of the enchantment. Show In Tooltip Boolean Whether the list of enchantments should be shown on the item's tooltip.
24	minecraft:dyed_color	Color of dyed leather armor.	As follows: Name Type Description Color Int The RGB components of the color, encoded as an integer. Show In Tooltip Boolean Whether the armor's color should be shown on the item's tooltip.
25	minecraft:map_color	Color of the markings on the map item model.	As follows: Name Type Description Color Int The RGB components of the color, encoded as an integer.
26	minecraft:map_id	The ID of the map.	As follows: Name Type Description ID VarInt
27	minecraft:map_decorations	Icons present on a map.	As follows: Name Type Decorations Data NBT Always a Compound Tag.
28	minecraft:map_post_processing	Used internally by the client when expanding or locking a map. Display extra information on the item's tooltip when the component is present.	As follows: Name Type Decorations Type VarInt Enum Type of post processing. Can be either: 0 - Lock 1 - Scale
29	minecraft:charged_projectiles	Projectiles loaded into a charged crossbow.	As follows: Name Type Decorations Number Of Projectiles VarInt The number of elements in the following array. Projectiles Array of Slot The projectiles.
30	minecraft:bundle_contents	Contents of a bundle.	As follows: Name Type Decorations Number Of Items VarInt The number of elements in the following array. Items Array of Slot The projectiles.
31	minecraft:potion_contents	Visual and effects of a potion item.	As follows: Name Type Decorations Potion ID VarInt The ID of the potion type in the potion registry. Has Custom Color Boolean Whether this potion has a custom color. If false, it uses the default color associated with the potion type. Custom Color Int The RGB components of the color, encoded as an integer. Number Of Custom Effects VarInt The number of elements in the following array. Custom Effects Array of Potion Effect Any custom effects the potion might have. See Potion Effect.
32	minecraft:suspicious_stew_effects	Effects granted by a suspicious stew.	As follows: Name Type Description Number Of Effects VarInt Number of elements in the following array. Effect Type ID Array VarInt Enum The ID of the effect in the potion effect type registry. Duration VarInt The duration of the effect.
33	minecraft:writable_book_content	Description here.	Data here.
34	minecraft:written_book_content	Description here.	Data here.
35	minecraft:trim	Description here.	Data here.
36	minecraft:debug_stick_state	Description here.	Data here.
37	minecraft:entity_data	Description here.	Data here.
38	minecraft:bucket_entity_data	Description here.	Data here.
39	minecraft:block_entity_data	Description here.	Data here.
40	minecraft:instrument	Description here.	Data here.
41	minecraft:ominous_bottle_amplifier	Description here.	Data here.
42	minecraft:recipes	Description here.	Data here.
43	minecraft:lodestone_tracker	Description here.	Data here.
44	minecraft:firework_explosion	Description here.	Data here.
45	minecraft:fireworks	Description here.	Data here.
46	minecraft:profile	Description here.	Data here.
47	minecraft:note_block_sound	Description here.	Data here.
48	minecraft:banner_patterns	Description here.	Data here.
49	minecraft:base_color	Description here.	Data here.
50	minecraft:pot_decorations	Description here.	Data here.
51	minecraft:container	Description here.	Data here.
52	minecraft:block_state	Description here.	Data here.
53	minecraft:bees	Description here.	Data here.
54	minecraft:lock	Description here.	Data here.
55	minecraft:container_loot	Description here.	Data here.

Other types

Common types used in multiple components are described below.

Block Predicate

Describes a predicate used when block filtering is necessary. It can be parameterized to account for the type of block, the values of specific block state properties, NBT data related to block entities, or any combination of the three.

Name	Type	Description
Has Blocks	Boolean	Whether this predicate is tied to specific types of blocks.
Blocks	Optional Block Set	See Block Set. Only present if Has Blocks is true.
Has Properties	Boolean	Whether this predicate is tied to specific properties of a block.
Number of Properties	Optional VarInt	Number of elements in the following array. Only present if Has Properties is true.
Properties	Optional Array of Property	See Property structure below. Only present if Has Properties is true.
Has NBT	Boolean	Whether this predicate is tied to specific block entity data.
NBT	Optional NBT	Only present is Has NBT is true.

The Property structure is defined as follows:

Name	Type	Description
Name	String	Name of the block state property.
Is Exact Match	Boolean	Whether this is an exact value match, as opposed to ranged.
Exact Value	Optional String	Value of the block state property. Only present in exact match mode.
Min Value	Optional String	Minimum value of the block state property range. Only present in ranged match mode.
Max Value	Optional String	Maximum value of the block state property range. Only present in ranged match mode.

Block Set

Represents a list of block types, either directly (enumerated IDs) or indirectly (block tag).

Name	Type	Description
Type	VarInt	Identifier used to determine the data that follows. It can be either: 0 - Represents a named set of blocks, defined by a tag. Anything else - Represents an enumerated set of blocks, defined by block IDs.
Tag name	Optional Identifier	A tag representing a set of blocks. Only present if Type is 0.
Block IDs	Optional Array of VarInt	An array of block IDs. Only present if Type is not 0. The size of the array is equal to Type - 1.

Potion Effect

Describes all the aspects of a potion effect.

Name	Type	Description
Type ID	VarInt Enum	The ID of the effect in the potion effect type registry.
Details	Detail	See Detail structure below.

The Detail structure is defined as follows:

Name	Type	Description
Amplifier	VarInt
Duration	VarInt	-1 for infinite.
Ambient	Boolean	Produces more translucent particle effects if true.
Show Particles	Boolean	Completely hides effect particles if false.
Show Icon	Boolean	Shows the potion icon in the inventory screen if true.
Has Hidden Effect	Boolean	Used to store the state of the previous potion effect when a stronger one is applied. This guarantees that the weaker one will persist, in case it lasts longer. The following information needs to be added to this page: This behavior seems to be entirely server-sided. Does the presence of this field actually has any noticeable impact on the client?
Hidden Effect	Optional Detail	Only present if Has Hidden Effect is true.