Stream events

Stream public Session events over Server-Sent Events.

GET /api/v1/cloud/sessions/{session_id}/events/stream

Streams public Session events as Server-Sent Events.

Path parameters

Parameter	Type	Description
session_id	string	Session ID with the sess_ prefix

Query parameters

Parameter	Type	Description
event_deltas[]	string	Optional, repeatable. Allowed values are agent.message and agent.thinking. Selects event types to stream incrementally on this connection.

Headers

Header	Required	Description
Authorization	Yes	Bearer $QODER_PAT
Accept	No	Use text/event-stream
Last-Event-ID	No	Resumes after the specified buffered event ID. When it equals an in-progress event delta ID, historical deltas for that event are skipped and only future output is sent.

Example request

curl -N -X GET "https://api.qoder.com/api/v1/cloud/sessions/sess_019e392c0d1e74e095d21ea4c6b41def/events/stream" \
  -H "Authorization: Bearer $QODER_PAT" \
  -H "Accept: text/event-stream"

Request both supported event delta types:

curl -N -G "https://api.qoder.com/api/v1/cloud/sessions/sess_019e392c0d1e74e095d21ea4c6b41def/events/stream" \
  -H "Authorization: Bearer $QODER_PAT" \
  -H "Accept: text/event-stream" \
  --data-urlencode "event_deltas[]=agent.message" \
  --data-urlencode "event_deltas[]=agent.thinking"

Response

The response uses text/event-stream. Each data: payload is one of:

• a complete public Event object, called a buffered event below, which is recorded in Session event history and includes an SSE id: cursor;
• a stream-only event delta frame, whose SSE id: is the ID of the event being streamed.

The model request boundaries in buffered output follow the model request span event schemas.

Stream format

Each event is emitted with standard SSE fields:

id: evt_019e392c0d787cfaa21bda98e06cd913
event: user.message
data: {"id":"evt_019e392c0d787cfaa21bda98e06cd913","type":"user.message","content":[{"type":"text","text":"Hello"}],"processed_at":"2026-05-18T03:40:48.888851795Z"}

id: evt_a1b2c3d4e5f6a7b8
event: agent.message
data: {"id":"evt_a1b2c3d4e5f6a7b8","type":"agent.message","content":[{"type":"text","text":"Hello! How can I help you today?"}],"processed_at":"2026-05-18T03:40:50.123456789Z"}

id: evt_b2c3d4e5f6a7b8c9
event: session.status_idle
data: {"id":"evt_b2c3d4e5f6a7b8c9","type":"session.status_idle","stop_reason":{"type":"end_turn"},"processed_at":"2026-05-18T03:40:50.987654321Z"}

The server sends : heartbeat comment lines periodically to keep the connection alive.

Event delta frames

Incremental agent.message output emits event_start followed by one or more event_delta frames. Incremental agent.thinking output emits only event_start.

id: evt_00jjujk9fbnr55q5rtyp
event: event_start
data: {"event":{"id":"evt_00jjujk9fbnr55q5rtyp","type":"agent.thinking"},"type":"event_start"}

id: evt_00jjujk9fbnr4wkj2gh8
event: event_start
data: {"event":{"id":"evt_00jjujk9fbnr4wkj2gh8","type":"agent.message"},"type":"event_start"}

id: evt_00jjujk9fbnr4wkj2gh8
event: event_delta
data: {"delta":{"content":{"text":"Hello","type":"text"},"index":0,"type":"content_delta"},"event_id":"evt_00jjujk9fbnr4wkj2gh8","type":"event_delta"}

Each frame’s SSE id: is the ID of the event being streamed. Its JSON payload does not include top-level id or processed_at fields. Event delta frames do not appear in list/history responses. Retained deltas are available for reconnect only while the event is still in progress; after the buffered agent.message is written, historical deltas are no longer replayed.

Reconnection

For normal buffered events, Last-Event-ID resumes after the specified event. An in-progress incrementally streamed event has additional behavior because its event_start, all event_delta frames, and final buffered event share one ID:

1. A cursor before the current event_start replays its retained start and historical deltas while generation is still in progress.
2. A cursor equal to the in-progress event ID skips its historical deltas and receives only future deltas and the final buffered event.
3. After generation completes, reconnecting from an earlier buffered event returns the final agent.message, not historical deltas.

To rebuild an entire in-progress event, reconnect from the buffered event immediately before its event_start and reprocess frames keyed by their shared event ID. See SSE Event Stream for the complete client guidance.

Errors

HTTP	Type	Trigger
400	invalid_request_error	Last-Event-ID identifies an archived or non-public event, or event_deltas[] contains an unsupported value
401	authentication_error	PAT invalid or expired
404	not_found_error	Session or the event referenced by Last-Event-ID does not exist

Example: 404 Session not found

{
  "error": {
    "message": "Session 'sess_doesnotexist_xxxxxxxxxxxxxxxxxxxxxxxx' was not found.",
    "type": "not_found_error"
  },
  "request_id": "b5822072-f264-48da-9d61-6d48ffb07551",
  "type": "error"
}

See Errors for the full error envelope.