Item functions modify the nature of an item in loot tables and trade tables.

TODO can enchantments be prefixed with minecraft:/whatever?

{
    "type": "item",
    "name": "minecraft:diamond",
    "weight": 1,
    "functions": [
        {
            "function": "set_count",
            "count": {
                "min": 1,
                "max": 3
            }
        }
    ]
}

Most of the functions here were tested in trade tables only.

These functions are usable in trade tables and loot tables only.

These functions should be under the functions array.

None accept Molang.

No Java additional functions or properties were successful.

All may be prefixed with any sequence of text followed by a colon, like minecraft:exploration_map or d1245436576u:fio2ejfoijfiowejf::::::exploration_map

General ​

A handful of functions are available for basic item properties. These functions are usable on any item.

Count ​

The set_count function sets the count for that item entry.

{
    "function": "set_count",
    "count": {
        "min": 2,
        "max": 4
    }
}

The "count" property determines how many of that item should be yielded; it can either be provided as an integer or a range object. Provided counts values may be larger than the stack size for that item. When this happens, the item will leak into other slots if in a container or separate into multiple different item stacks if dropped into the world. The count property actually defaults to 0, so it should always be included.

Name ​

The name of an item can be set using the set_name function. Names are visible in the user interface when hovering over an item. Names can be changed by players using anvils.

{
    "function": "set_name",
    "name": "Cursed Bow"
}

The name to give the item is given with the string "name" property. By default, name text appears italicized. However, item names support format codes, and §r can be inserted at the start of the text to reset it to non-italics. Raw text is unsupported in item names. \n can be used for newlines.

Lore ​

The set_lore function sets the lore for an item.

{
    "function": "set_lore",
    "lore": ["", ""]
}

The "lore" property configures the lore. It can be represented as either a string or an array of strings. All lore strings support format codes but do not support localization. In the array form, each string represents a new line of lore. Each such string's formatting context is independent, meaning formatting will reset with each string. By default, purple and italicized text is used for lore; this can be reset by prepending the reset format code (§r) to each string as necessary. \n can be used within any lore string to form a newline while preserving the current formatting context.

Data ​

set_data establishes the data for the given item, similar to the argument in the /give command. If used on a block, it will set the block's data value. If used on an item, it will set it's aux value. Unlike the command, however, set_data cannot set the durability of an item. For that, use durability.

{
    "function": "set_data",
    "data": 2
}

The "data" property sets the item's data. If not provided, it will default to 0. "data" can either be provided as an integer or a range object.

As an integer:

"data": 1

As a range object:

"data": {
	"min": 0,
	"max": 5
}

The object form will randomly select a data value inclusively between the provided minimum and maximum each instance this function's item entry is selected.

Block State ​

random_block_state sets an individual block state for a block.

{
    "function": "random_block_state",
    "block_state": "wiki:color",
    "values": 3
}

Sets a block state for a block.

block_state: Required string name of block state.

values: Can be a number or a range object.

Defaults to 0… kinda required otherwise pointless? IDK…

Aux Value ​

random_aux_value

{
    "function": "random_aux_value",
    "values": {
        "min": 2,
        "max": 4
    }
}

Sets the auxiliary value of an item.

values: Can be an integer or a range object.

If using a range object, it will randomly choose the values uniformly(each value has the same chance of being chosen).

Only used for auxiliary value; won't, for example, set damage of a tool but will set color of wool.

It overrides any provided auxiliary value as identifier :suffix, like minecraft:wool:10.

Also works for block data.

Durability ​

Item durability can be set using the set_damage function.

{
    "function": "set_damage",
    "damage": {
        "min": 0.5,
        "max": 1
    }
}

Sets the damage value of this item.

damage: Can either be a set number or a range object. Allowed values range from 0.0-1.0.

Note that if this item has no durability component, this function will be ignored.

Item-Specific Data ​

Some functions are only usable by a certain set of items. See each function for which items are relevant.

Heat Item ​

furnace_smelt

{
    "function": "furnace_smelt"
}

Auto-implies that the entity must’ve been on fire when they died. Vanilla files use a function condition for this, but even removing that condition still implies that the entity must’ve died on fire for the furnace_smelt function to trigger.

Book Contents ​

set_book_contents

{
    "function": "set_book_contents",
    "title": "Wiki Book",
    "author": "Bedrock Wiki",
    "pages": ["Example page number one", "Example page number 2"]
}

Sets the data for a book.

Can only be used on minecraft:writable_book or minecraft:written_book.

author: String name of the author.

title: String name of the book.

pages: Array of strings — each string is the contents of that page.

Supports up to 50 strings and 798 characters per string 12,800‌ character limit across all pages. Use \n in the string (not \\n) to add newlines.

Can’t use tabs.

Can use color codes; Each different page string resets the color codes each time.

Exploration Map ​

exploration_map

{
    "function": "exploration_map",
    "destination": "village"
}

Trade Table info:

destination:

Currently only monument and mansion are allowed.

Nothing else, not even buried treasure (this one looks like it’ll work — names the map right instead of Unknown Map like the others, but it doesn’t point anywhere). 😦

Loot Table info:

destination:

Works for any /locate location (see old recipe notes for caveats there; this is for container loot tables).

Only works if in the appropriate dimension.

If a mansion or monument, gets named, colored, and icon’d correctly, corresponding to the right marker decoration.

If invalid or no destination is given, shows no marker but still has the river and ocean lines on the map.

Works in both containers and entity equipment and drops.

Keep in mind how only 2 locations worked from traders.

Banner Type ​

set_banner_details

{
    "function": "set_banner_details",
    "type": 1 // Ominous Banner
}

Sets type of a minecraft:banner or the banner on a minecraft:shield (only usable on these).

type: Can only be 0 or 1.

• 0 is a White Banner.
• 1 is an Ominous Banner.

base_color: Can be set for banners of type 0 and sets the color of the banner. patterns: Is an array of banner patterns and colors to be applied to the banner. Up to 6 patterns can be applied.

Random Dyeing ​

random_dye

{
    "function": "random_dye"
}

Randomly dyes dyeable items. Such as leather horse armor, leather armor, and wolf armor.

It doesn’t work on wool or other related items.

Spawn Eggs ​

set_actor_id

{
    "function": "set_actor_id",
    "id": "minecraft:chicken"
}

Usable with spawn eggs.

id: The identifier for the mob.

In trade tables, if the id property is omitted, it defaults to the trader's identifier.

Container Contents ​

fill_container

{
    "function": "fill_container",
    "loot_table": "loot_tables/chests/chest_loot.json"
}

Sets the contents of a container item/block. Allows container items such as shulker boxes and bundles to contain loot itself.

loot_table: Path to loot table file from behavior pack root.

The loot_table property is needed or it will just be the normal item. It cannot point to the same loot table the item is in. Works in containers and both entity stuff and blocks

Potion Type ​

set_potion

{
    "function": "set_potion",
    "id": "poison"
}

Sets the potion type of this item. Allowed item types are: minecraft:potion, minecraft:splash_potion, minecraft:lingering_potion, and minecraft:arrow.

id: the name of the potion type. Here is the list of all the Potion Types.

Ominous Bottle Amplifier ​

set_ominous_bottle_amplifier

{
    "function": "set_ominous_bottle_amplifier",
    "amplifier": {
        "min": 0,
        "max": 4
    }
}

Sets the minecraft:ominous_bottle potion effect amplifier.

amplifier: can be a set number or a range object. Allowed values are 0-4.

Suspicous Stew Effect ​

set_ominous_bottle_amplifier

{
    "function": "minecraft:set_stew_effect",
    "effects": [
        {
            "id": 0 // night vision
        },
        {
            "id": 3 // blindness
        }
    ]
}

Sets the effect of a minecraft:suspicious_stew item.

id can be set to any integer from 0 to 12.

Enchanting ​

These functions control whether an item has an enchantment.

Enchant for Trading ​

enchant_book_for_trading

{
    "function": "enchant_book_for_trading"
}

Documented in trade tables.

Level-Based Enchantments ​

enchant_with_levels enchants items using enchantment table logic, optionally allowing for treasure enchantments.

{
    "function": "enchant_with_levels",
    "levels": {
        "min": 15,
        "max": 21
    },
    "treasure": true
}

Enchants books as though off an Enchanting Table with the given levels.

Unlike the Enchanting Table, it doesn’t cap at 30, otherwise seems symmetrical.

Level 99999 gives ludicrously powerful books… with pretty much every possible enchantment on them.

treasure: Enables treasure enchantments as possibilities for that item. Boolean, defaults to false. If false, curses can't appear as possibilities; if true, they can.

levels: Can be a number or a range object. Defaults to 0. Can be negative, but will just be remapped as though 0.

Random Enchantments ​

enchant_randomly

{
    "function": "enchant_randomly"
}

Randomly picks a count of enchantments and their strengths for the given item.

treasure:Enables treasure enchantments as possibilities for that item. Boolean, defaults to false.

Enchant Gear ​

enchant_random_gear

{
    "function": "enchant_random_gear",
    "chance": 0.5 // 50% chance of being enchanted
}

Randomly picks a count of enchantments and their strengths for the given item.

Pretty much like enchant_randomly, but seemingly no treasure enchantments.

Not working on shears, but does even work on carrot-on-a-stick.

chance: the probability of this item to get an enchanted at all. Allowed values ranges from 0.0-1.0. Defaults to 0. Note that going over 1.0 doesn't make it more "enchanted".

Specific Enchantments ​

specific_enchants

{
    "function": "specific_enchants",
    "enchants": [
        {
            "id": "unbreaking",
            "level": [1, 3]
        }
    ]
}

Applies a specific set of enchantments.

enchants:

Can be a string array or object. Here is the list of all Enchantment Types.

For array, any mix of strings or objects (see below).

For string, an enchantment id.

For object:

id: The identifier for the enchantment.

level:

Optional, defaults to 1 Can be an exact number or a 2-valued array, representing min and max, inclusive.

Example:

{
    "function": "specific_enchants",
    "enchants": [ 
        "mending",
        {
            "id": "fortune",
            "level": [1, 3]
        }
    ]
}

External Factors ​

External conditions that affect item drops.

Held Tool Looting Enchantment ​

looting_enchant

{
    "function": "looting_enchant",
    "count": {
        "min": 0,
        "max": 1
    }
}

Increases the number of items dropped based on the Looting Enchantment level used to kill the entity.

Count can be an integer or a range object.

Explosion Decay ​

explosion_decay

{
    "function": "explosion_decay"
}

By default, always survives. If in an explosion, has a chance of not dropping based on explosion power at that block’s location

Entity Color ​

set_data_from_color_index

{
    "function": "set_data_from_color_index"
}

Sets the data value of the block to the value of the minecraft:color component on the entity

Trader Material Type ​

trader_material_type

{
    "function": "trader_material_type"
}

Only in trades? Maybe it can work somewhere in loot.

Type Identifiers

List of all string values used in functions that use string values such as potion types and enchantments.

Potion Types ​

Used by the set_potion function.

• "water"
• "mundane"
• "long_mundane"
• "awkward"
• "nightvision"
• "long_nightvision"
• "invisibility"
• "long_invisibility"
• "leaping"
• "long_leaping"
• "strong_leaping"
• "fire_resistance"
• "long_fire_resistance"
• "swiftness"
• "long_swiftness"
• "strong_swiftness"
• "slowness"
• "long_slowness"
• "strong_slowness"
• "water_breathing"
• "long_water_breathing"
• "healing"
• "strong_healing"
• "harming"
• "strong_harming"
• "poison"
• "long_poison"
• "strong_poison"
• "regeneration"
• "long_regeneration"
• "strong_regeneration"
• "strength"
• "long_strength"
• "strong_strength"
• "weakness"
• "long_weakness"
• "wither"
• "turtle_master"
• "long_turtle_master"
• "strong_turtle_master"
• "slow_falling"
• "long_slow_falling"
• "wind_charge"
• "weaving"
• "oozing"
• "infested"

Enchantment Types ​

Used by the specific_enchants function.

• "protection"
• "fire_protection"
• "feather_falling"
• "blast_protection"
• "projectile_protection"
• "unbreaking"
• "mending"
• "respiration"
• "depth_strider"
• "frost_walker"
• "aqua_affinity"
• "soul_speed"
• "swift_sneak"
• "sharpness"
• "smite"
• "bane_of_arthropods"
• "fire_aspect"
• "knockback"
• "looting"
• "efficiency"
• "fortune"
• "silk_touch"
• "power"
• "punch"
• "flame"
• "infinity"
• "multishot"
• "piercing"
• "quick_charge"
• "luck_of_the_sea"
• "lure"
• "impaling"
• "riptide"
• "loyalty"
• "channeling"
• "curse_of_binding"
• "curse_of_vanishing"
• "density"
• "breach"
• "wind_burst"
• "lunge"