handleRetrieverStart

handleRetrieverStart(
  retriever: Serialized,
  query: string,
  runId: string = ...,
  _parentRunId: string | undefined = undefined,
  _tags: string[] | undefined = undefined,
  _metadata: Record<string, unknown> | undefined = undefined,
  runName: string | undefined = undefined
): Promise<CallbackManagerForRetrieverRun>