Return a session's transcript, and whether it is complete.

Transcript records reach the logs database through an asynchronous pipeline, so a read taken immediately after a session ends can return a short record. transcript_complete is true only when everything the session reported writing is present, across both the spoken transcript and the tool activity in actions. A caller that needs the whole record should re-request with exponential backoff until it is true, or until its own time limit passes, keeping the last response either way.

A time limit is required rather than optional. transcript_complete never turns true for a session still in progress, for a session on a channel that reports no expected count (only voice reports one today), or for a session that ended before the field was introduced - so a caller polling without a limit would never stop.

{
  "transcription": [
    {
      "lang": "en-US",
      "source": "user"
    }
  ],
  "transcript_complete": true
}