Recorded live from POST /agents/{agent_id}/chats/{chat_id}/query (is_stream=true)
on 2026-07-31, via a raw httpx streaming request (bypassing httpx_sse parsing)
so the exact wire framing is visible.

Content-Type: text/event-stream; charset=utf-8

Key findings:
- No `event:` field is ever sent -- httpx_sse's `connect_sse` therefore reports
  every frame as the default event name "message". Event identity MUST be read
  from the JSON payload's "type" field, not the SSE event name.
- Response text lives at the top-level "text" key of each payload.
- The stream always ends with the literal sentinel line `data: [DONE]`.
- Observed types in this capture: metadata, response, end_response, done.

Raw frames (one `data:` line each, separated by a blank line per SSE spec):

data: {"text": "", "extended_text": null, "type": "metadata", "subtype": null, "data": {"message_id": "REDACTED_MESSAGE_ID"}, "elapsed_ms": null}

data: {"text": "1,", "extended_text": null, "type": "response", "subtype": null, "data": null}

data: {"text": " 2, 3.", "extended_text": null, "type": "response", "subtype": null, "data": null}

data: {"text": "", "extended_text": null, "type": "end_response", "subtype": null, "data": null}

data: [DONE]

