Wall-clock time spent inside Provider.Search() for this invocation.
Result rows from this provider, with metadata already stamped.
OptionalscopeID?: stringScope ID when running per-scope; undefined when unconstrained.
Source type as reported by the provider (e.g. 'vector', 'fulltext').
Callback fired the moment an individual provider's
Search()resolves — before fusion, dedup, permission filtering, or rerank. Used by SearchEngine.streamSearch to emitproviderevents as each provider returns rather than waiting for the whole pipeline. The callback runs inside the provider's promise chain, so any throw it raises will cancel that provider's contribution but won't take down the search.