Bedrock Edition level format/Item format

Item NBT is used both in the player's inventory and Ender inventory, and in chest block entities, dropped item entities, etc.

Item Stack Base

 * The item ID
 * Number of items stacked in this inventory slot.
 * The additional data value. Note that this tag does not store items' damage value.
 * Unknown.
 * (May not exist) What block is placed when using this item on a block.
 * (May not exist) Additional information about the item, discussed more bellow.
 * 1 for "lock in slot". 2 for "lock in inventory".
 * 1 if keeping on death.
 * (May not exist) Controls what block types this item can destroy.
 * An item ID.
 * (May not exist) Controls what block types this block may be placed on.
 * An item ID.
 * An item ID.

General Tags

 * (May not exist) The damage value for this item. Defaults to 0.
 * (May not exist) Display properties.
 * (May not exist) The JSON text component to use to display the item.
 * (May not exist) List of strings to display as lore for the item.
 * (May not exist) A line of text for the lore of an item.
 * (May not exist) Number of experience levels to add to the base level cost when repairing, combining, or renaming this item with an Anvil.

Enchantment Tags

 * Contains enchantments on this item.
 * A single enchantment.
 * The id of the enchantment.
 * The level of the enchantment, where 1 is level 1. Values are clamped between 0 and 255 when reading.

Bucket of Aquatic Mob

 * Whether entity color, state, and id are used to generate the bucket item's name. Defaults to 1.
 * (May not exist) The custom name of entity in it. Used to generate the bucket item's name.
 * (May not exist) The translation key of a color. Used to generate the bucket item's name.
 * (May not exist) The translation key of another color. Used to generate the bucket item's name.
 * (May not exist) The translation key of entity's state. Used to generate the bucket item's name.
 * (May not exist) Unknown. Used to generate the bucket item's name.
 * entity

Lodestone Compass

 * The id of lodestone to track.

Filled Map

 * (May not exist) Unknown.
 * The uuid of the map used in this item.
 * The index of the map's name.
 * (May not exist) Whether the map displays player markers.
 * (May not exist) Unknown.
 * (May not exist) Unknown.

Horse Armor

 * (May not exist) The color of the leather armor.

Glow Stick

 * (May not exist) Unknown.

Banner

 * (May not exist) 1 is ominous banner‌.
 * List of all patterns applied to the banner.
 * : An individual pattern.
 * : The pattern id code. SeeBanner.
 * : The base color of the pattern. SeeBanner.

Firework

 * List of compounds representing each explosion this firework causes.
 * Indicates the flight duration of the firework (equals the amount of gunpowder used in crafting the rocket). Can be anything from -128 to 127.
 * Indicates the flight duration of the firework (equals the amount of gunpowder used in crafting the rocket). Can be anything from -128 to 127.
 * Indicates the flight duration of the firework (equals the amount of gunpowder used in crafting the rocket). Can be anything from -128 to 127.

Firework Star

 * The explosion effect contributed by this firework star.
 * Explosion
 * The color of this firework star.

Written Book

 * The author of this book.
 * The title of this book.
 * Unknown.
 * The list of pages in the book.
 * A single page in the book.
 * The test in this page.
 * Unknown.
 * The copy tier of the book. 0 = original, 1 = copy of original, 2 = copy of copy.

Book and Quills

 * (May not exist) The list of pages in the book.
 * A single page in the book.
 * The test in this page.
 * Unknown.

Shulker box

 * List of items in the shulker box.
 * compound

Crossbow

 * The items this crossbow has charged.
 * ItemStackBase

Potion

 * (May not exist) True if item is brewed in brewing stand