Create a reusable definition with ordinary typed references or inline sequence steps.

Use kind=all_of/any_of/not/at_least/consecutive with definition_ids. For kind=sequence use steps=[{condition: {kind: condition_ref, definition_id: ...}, within_bars: 6}]. Each step accepts condition, optional id, within_bars and hold_bars. builder_discover(ref="condition:sequence") documents the canonical step grammar. The standard source parser validates inline predicates and references. Policy exits are attached as separate exit rules.