mcf-predicate

name	mcf-predicate
description	Create and modify Minecraft Java Edition predicate files and inline predicates. Use when building condition checks for loot tables, advancements, target selectors, or execute commands. Covers all 20+ predicate types with complete field reference.
license	MIT
compatibility	opencode
metadata	{"version":"1.0","game-version":"26.1.2","category":"minecraft-datapack"}

Minecraft Predicates (Loot Conditions)

File Location

data/<namespace>/predicate/<path>.json

Usage

• Target selectors: @a[predicate=namespace:path]
• Execute command: execute if predicate namespace:path
• Inline predicate (SNBT in commands):

execute if predicate {condition:"minecraft:location_check",predicate:{biome:"minecraft:plains"}}

• Loot tables: in conditions arrays within pools/entries
• Advancements: in trigger conditions and player predicates

File Format

Object form (single predicate):

{
  "condition": "minecraft:entity_properties",
  "entity": "this",
  "predicate": { ... }
}

Array form (multiple = all_of):

[
  { "condition": "minecraft:location_check", ... },
  { "condition": "minecraft:weather_check", ... }
]

Predicate Types Reference

Logical Predicates

all_of - Logical AND:

{ "condition": "minecraft:all_of", "terms": [...] }

any_of - Logical OR:

{ "condition": "minecraft:any_of", "terms": [...] }

inverted - Logical NOT:

{ "condition": "minecraft:inverted", "term": { ... } }

reference - Reference another predicate file:

{ "condition": "minecraft:reference", "name": "namespace:path" }

Entity Predicates

entity_properties - Test entity properties:

{
  "condition": "minecraft:entity_properties",
  "entity": "this",
  "predicate": {
    "type": "minecraft:zombie",
    "location": { "biome": "minecraft:desert" },
    "flags": { "is_on_fire": true },
    "nbt": "{Health:20.0f}"
  }
}

Entity targets: this, attacker, direct_attacker, attacking_player, target_entity, interacting_entity

entity_scores - Test scoreboard scores:

{
  "condition": "minecraft:entity_scores",
  "entity": "this",
  "scores": {
    "my_objective": { "min": 1, "max": 10 }
  }
}

Location & Block Predicates

location_check - Test location with offset:

{
  "condition": "minecraft:location_check",
  "offsetX": 0, "offsetY": 1, "offsetZ": 0,
  "predicate": {
    "block": { "blocks": ["minecraft:stone"] },
    "biome": "minecraft:plains",
    "dimension": "minecraft:overworld",
    "light": { "light": { "min": 7 } }
  }
}

Requires loot context origin.

block_state_property - Test block state:

{
  "condition": "minecraft:block_state_property",
  "block": "minecraft:oak_door",
  "properties": { "half": "upper", "open": "true" }
}

Requires loot context block_state.

Item Predicates

match_tool - Test the used tool/item:

{
  "condition": "minecraft:match_tool",
  "predicate": {
    "items": ["minecraft:diamond_pickaxe"],
    "enchantments": [{ "enchantment": "minecraft:silk_touch", "levels": { "min": 1 } }]
  }
}

Requires loot context tool.

Damage & Combat Predicates

damage_source_properties - Test damage source:

{
  "condition": "minecraft:damage_source_properties",
  "predicate": {
    "tags": [{ "id": "minecraft:is_fire", "expected": true }],
    "is_direct": true
  }
}

Requires loot context origin and damage_source.

killed_by_player - Entity killed by player:

{ "condition": "minecraft:killed_by_player" }

survives_explosion - 1/explosion_radius probability:

{ "condition": "minecraft:survives_explosion" }

Passes automatically if no explosion_radius context.

Random Predicates

random_chance - Random probability (0.0-1.0):

{
  "condition": "minecraft:random_chance",
  "chance": { "type": "minecraft:constant", "value": 0.5 }
}

random_chance_with_enchanted_bonus - Enchantment-affected probability:

{
  "condition": "minecraft:random_chance_with_enchanted_bonus",
  "enchantment": "minecraft:looting",
  "enchanted_chance": {
    "type": "minecraft:linear",
    "base": 0.025,
    "per_level_above_first": 0.01
  },
  "unenchanted_chance": 0.025
}

Requires attacking_entity context.

table_bonus - Enchantment-level-indexed probability table:

{
  "condition": "minecraft:table_bonus",
  "enchantment": "minecraft:fortune",
  "chances": [0.0, 0.33, 0.5, 0.66, 1.0]
}

Requires tool context.

Environment Predicates

weather_check - Test weather:

{
  "condition": "minecraft:weather_check",
  "raining": true,
  "thundering": false
}

time_check - Test game time:

{
  "condition": "minecraft:time_check",
  "clock": "minecraft:overworld",
  "value": { "min": 0, "max": 13000 },
  "period": 24000
}

With period, time is modulo'd first (e.g., period=24000 checks day time only).

environment_attribute_check (v26.1) - Test environment attribute:

{
  "condition": "minecraft:environment_attribute_check",
  "attribute": "minecraft:temperature",
  "value": 0.8
}

Requires origin if attribute varies by location.

enchantment_active_check - Test if enchantment is active:

{
  "condition": "minecraft:enchantment_active_check",
  "active": true
}

Requires enchantment_active context.

Value Predicates

value_check - Compare a number provider against a range:

{
  "condition": "minecraft:value_check",
  "value": { "type": "minecraft:score", "target": "this", "score": "my_obj" },
  "range": { "min": 0, "max": 100 }
}

Common Patterns

Check if player is in a specific biome

{
  "condition": "minecraft:entity_properties",
  "entity": "this",
  "predicate": {
    "location": { "biome": "minecraft:desert" }
  }
}

Check if block below player is grass

{
  "condition": "minecraft:location_check",
  "offsetY": -1,
  "predicate": {
    "block": { "blocks": ["minecraft:grass_block"] }
  }
}

50% chance

{ "condition": "minecraft:random_chance", "chance": 0.5 }