Tag operations

Types

• FGameplayTag: one registered hierarchical name.
• FGameplayTagContainer: explicit tags plus cached parent relationships.
• FGameplayTagQuery: serialized any/all/none expression tree evaluated against a container.

Use containers instead of TArray<FGameplayTag> for tag-set behavior.

Matching direction

Given stored tag State.Movement.Sprinting:

Test	Result
hierarchical HasTag(State.Movement)	true
exact HasTagExact(State.Movement)	false
hierarchical query for State.Movement.Sprinting.Fast	false
exact query for State.Movement.Sprinting	true

Matching is directional. A child satisfies a parent query; a parent does not satisfy a more specific child query.

For individual tags, MatchesTag includes parent matching and MatchesTagExact requires the literal tag. For containers, use HasTag, HasAny, and HasAll or their Exact variants.

Empty semantics

Epic documents that an empty input container returns false for HasTag/Any-style tests, while All-style tests return true because no required tag is missing. Empty query expressions have similar logical identities. Test empty authored queries; a missing requirement can otherwise silently allow everything.

Query selection

Use direct container operations for simple code-owned checks. Use FGameplayTagQuery when:

• designers author nested any/all/none logic;
• the rule is stored in a Data Asset/Table;
• multiple systems evaluate the same serialized rule.

Example prerequisite:

ALL(ANY(State.Weapon.Rifle, State.Weapon.Pistol), NONE(State.Disabled, State.Dead))

Keep queries named/documented. Dense anonymous query trees become difficult to debug.

Blueprint implementation

Use Gameplay Tag and Gameplay Tag Container variable types and the Gameplay Tags Blueprint library functions shown by the context menu. Confirm exact versus non-exact node choice in UE 5.8; do not compare ToString output.