Components Reference

Fields under the components section are mapped directly to Minecraft entity attributes or data components by ComponentMapper.

Attribute fields

Field	Type	Description
max_health	double	Maximum health points.
movement_speed	double	Movement speed (vanilla default ~0.25).
attack_damage	double	Melee attack damage.
attack_speed	double	Attack speed.
attack_knockback	double	Knockback strength on hit.
follow_range	double	Maximum target tracking distance (blocks).
knockback_resistance	double	Knockback resistance, 0.0–1.0.
armor	double	Armor value.
armor_toughness	double	Armor toughness.
luck	double	Luck value.
flying_speed	double	Flying speed (flying mobs only).
spawn_reinforcements	double	Zombie reinforcement call chance, 0.0–1.0.
scale	double	Render scale multiplier (1.0 = vanilla size).
step_height	double	Block height the mob can step onto directly.
jump_strength	double	Jump strength (rideable mobs such as horses).
safe_fall_distance	double	Fall distance that causes no damage.
fall_damage_multiplier	double	Fall damage multiplier.
burning_time	double	Burn duration multiplier once ignited.
explosion_knockback_resistance	double	Explosion knockback resistance.
oxygen_bonus	double	Underwater breathing bonus.
water_movement_efficiency	double	Movement efficiency in water.
movement_efficiency	double	Movement efficiency on ground.

NOTE

All of the above are vanilla entity attributes. An entry is ignored when the attribute does not exist on the target entity. Applying max_health also heals the mob up to the new maximum.

Appearance and behavior fields

Field	Type	Description
custom_name	string	Entity display name; supports MiniMessage format.
custom_name_visible	boolean	When true, name tag is always visible; when false, it only shows on hover.
persistent	boolean	Prevent natural despawn when no players are nearby.
silent	boolean	Suppress all mob sounds.
invulnerable	boolean	Immune to all damage.
no_ai	boolean	Disable AI (mob stops moving and attacking).
glowing	boolean	Show outline glow effect.
gravity	boolean	Whether the mob is affected by gravity.
fire_ticks	int	Initial fire duration in ticks.
freeze_ticks	int	Initial freeze duration in ticks (powder snow effect).
absorption	double	Initial absorption amount (yellow hearts).
visual_fire	boolean	Force the burning visual effect without dealing fire damage.
collidable	boolean	Whether the mob takes part in entity collision (pushing).
fire_immune	boolean	Whether the mob is immune to fire damage.

Loot fields

Field	Type	Description
loot_table	string	Associated loot table key: <namespace>:entities/<mob_id>, matching loot_tables/<mob_id>.yml.
can_pick_up_loot	boolean	Whether the mob can pick up items from the ground.
remove_when_far	boolean	Despawn when players move away (overrides persistent).

Equipment fields

Field	Type	Description
main_hand	ItemConfig	Main-hand item, top-level shorthand.
off_hand	ItemConfig	Off-hand item, top-level shorthand.
helmet	ItemConfig	Head slot, top-level shorthand.
chestplate	ItemConfig	Chest slot, top-level shorthand.
leggings	ItemConfig	Legs slot, top-level shorthand.
boots	ItemConfig	Feet slot, top-level shorthand.
equipment.<slot>	ItemConfig	Configure several slots under one equipment section.

Slot names under equipment accept these spellings (case-insensitive):

Slot	Accepted keys
Main hand	main_hand, hand
Off hand	off_hand
Head	helmet, head
Chest	chestplate, chest
Legs	leggings, legs
Feet	boots, feet

Each ItemConfig supports:

Field	Description
item	Item ID. Vanilla material names only, as minecraft:<id> (e.g. minecraft:diamond_sword).
drop_chance	Drop probability on death, 0.0–1.0. 0.0 means never drops.

components:
  main_hand:
    item: "minecraft:iron_sword"
    drop_chance: 0.05
  helmet:
    item: "minecraft:iron_helmet"
    drop_chance: 0.0
  equipment:
    legs:
      item: "minecraft:iron_leggings"
      drop_chance: 0.0
    # A bare material name works when only the item matters
    feet: "minecraft:iron_boots"

Unknown component keys are ignored silently

Keys under components must match the tables on this page exactly. ComponentMapper looks up a handler by key name and skips the entry when none is found, with no error and no log line. A misspelled key (for example noai instead of no_ai) produces no warning.

Mob-specific fields

Field	Applies to	Description
is_baby	Ageable mobs	Whether the mob spawns as a baby.
creeper_powered	Creeper	Whether the creeper is charged.
creeper_explosion_radius	Creeper	Explosion radius.
angry	Wolf	Whether the wolf is angered.
wolf_variant	Wolf	Wolf variant, from the minecraft:wolf_variant registry (e.g. pale, woods, ashen).
horse_color	Horse	WHITE, CREAMY, CHESTNUT, BROWN, BLACK, GRAY, DARK_BROWN.
horse_style	Horse	NONE, WHITE, WHITE_FIELD, WHITE_DOTS, BLACK_DOTS.
cat_type	Cat	Cat variant, from the minecraft:cat_variant registry.
parrot_variant	Parrot	RED, BLUE, GREEN, CYAN, GRAY.
frog_variant	Frog	Frog variant, from the minecraft:frog_variant registry.
axolotl_variant	Axolotl	LUCY, WILD, GOLD, CYAN, BLUE.
fox_type	Fox	RED, SNOW.
rabbit_type	Rabbit	BROWN, WHITE, BLACK, BLACK_AND_WHITE, GOLD, SALT_AND_PEPPER, THE_KILLER_BUNNY.
mushroom_type	Mooshroom	RED, BROWN.
panda_main_gene	Panda	NORMAL, LAZY, WORRIED, PLAYFUL, BROWN, WEAK, AGGRESSIVE.
panda_hidden_gene	Panda	Recessive gene; same values as above.
goat_screaming	Goat	Whether this is a screaming goat.
llama_color	Llama	CREAMY, WHITE, BROWN, GRAY.
llama_strength	Llama	Llama strength (1–5, determines chest capacity).
slime_size	Slime / Magma Cube	Size (1 = small, 2 = medium, 4 = large).
phantom_size	Phantom	Phantom size.
can_break_doors	Zombie types	Whether the mob can break doors.
villager_type	Villager / Zombie Villager	Biome type, from the minecraft:villager_type registry.
villager_level	Villager / Zombie Villager	Profession level (1–5).
villager_profession	Villager / Zombie Villager	Profession, from the minecraft:villager_profession registry.

An entry is skipped when the mob is not of the matching type, and an unrecognized enum or registry value is skipped as well.

Potion effect field

Field	Type	Description
potion_effect	string or string list	Potion effects applied on spawn. Use a single string for one effect or a list for several.

Each effect is one colon-separated string:

<effect type>:<duration ticks>[:<amplifier>]

Segment	Required	Description
Effect type	Yes	Vanilla effect ID, case-insensitive (speed, regeneration, fire_resistance, …).
Duration ticks	Yes	Duration in ticks.
Amplifier	No	Defaults to 0 (level I); 1 is level II.

components:
  potion_effect:
    - "speed:99999:1"
    - "regeneration:600"
  # A single effect can be written as a plain string
  # potion_effect: "fire_resistance:1200"

The mapping form is not supported

potion_effect parses only the colon-separated string above. Writing - type: SPEED with duration: and amplifier: keys raises no error, but the whole effect is discarded. ambient, particles and icon are not configurable. An unknown effect type, a missing duration, or an unparsable number also skips the entry silently.