The Slot data structure is how Minecraft represents an item and its associated data in the Minecraft Protocol.
|Present||Boolean||True if there is an item in this position; false if it is empty.|
|Item ID||Optional VarInt||The Data Generators for more information. Not present if present is false. Item IDs are distinct from block IDs; see|
|Item Count||Optional Byte||Not present if present is false.|
|NBT||Optional NBT||Not present if present is false. If 0 (TAG_End), there is no NBT data, and no further data follows. Otherwise the byte is the start of an NBT blob as shown below:|
COMPOUND '' LIST 'StoredEnchantments' COMPOUND SHORT 'id' SHORT 'lvl' END COMPOUND ... END ... END INT 'Unbreakable' ... END
See NBT for more information about the NBT format, and for the contained information and its format. Note that tool durability is included in NBT, among other things.
00 | empty slot 01 01 01 00 | a stone block 01 01 01 04 CA FE BA BE | a stone block with (made-up) NBT data