registry__search_artifacts when you know a name or topic but do not yet
have an artifact handle.
- Inputs: required
query; optionalkind,limit,semantic, andsession_id; plusrationalewhen Gateway enables it. - Limit: defaults to 50 and accepts at most 500.
- Returns: matching artifacts visible to the caller.
- Effect: read only.
registry__get_artifact or
registry__get_related_artifacts.