Minecraft Slot Source

Slot Source

Slot sources select specific slots from slot-holding objects (block entities, entities). Java Edition only. Used in loot tables and (from 26.3) command parameters.

Definition Format

Before 26.3, slot sources are loot-table-only. From 26.3: registry SLOT_SOURCE, data pack path slot_source (files in data/<namespace>/slot_source/; tags in tags/slot_source/).

A slot source is an object {type, ...} or a list of slot sources (list = group behavior).

Types

• group — terms (recursive list): concatenates the slot lists in order, duplicates included ([a,b] + [a,c] → [a,b,a,c]).
• filtered — item_filter (item stack predicate) + slot_source (recursive): drops slots whose item fails the test.
• limit_slots — limit (max count) + slot_source: keeps only the first limit slots in order.
• slot_range — picks slots from a source's slot range: source (from the loot context: block_entity, this, attacking_entity, last_damage_player, direct_attacker, target_entity, interacting_entity; default container) and slots (slot range like armor.chest, container.*). From 26.3, directly specifying a slot range in the slot_source command parameter converts to this type (source = the command's container context parameter).
• contents — gets slots from container components of the input slots' items: component (bundle_contents, charged_projectiles, or container) + slot_source (recursive). Empty/missing items or components yield no slots. From 26.3, /item targeting component slots first sets the component on the item when missing; (fill|override) gets all available component slots; bundle_contents fills in slot order, stopping when the bundle would overflow.
• reference (26.3) — name (slot source ID); cycles fail parsing.
• empty — no slots.