Stream session events

Subscribe to a Forward session event stream with SSE.

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

Streams session events as Server-Sent Events. The data payload uses the same Forward filtering model as the event history endpoint. New integrations that need streaming output should subscribe with event_deltas[].

Headers

Header	Required	Description
Authorization	Yes	Bearer <PAT>
Accept	Yes	text/event-stream
Last-Event-ID	No	Resume after this Event ID.

Path parameters

Parameter	Type	Required	Description
session_id	string	Yes	Session ID.

Query parameters

Parameter	Type	Required	Default	Description
event_deltas[]	string	No	-	Subscribe to streaming delta events for the specified public event types. Supports repeated parameters. Allowed values: agent.message, agent.thinking. See Event delta streaming.
include_tool_calls	boolean	No	true	Include tool call events.
include_thinking	boolean	No	true	Include thinking events.

Example request

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

Subscribe to text and thinking streaming delta events:

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

Example response

HTTP 200 OK

id: evt_xxx
event: agent.message
data: {"id":"evt_xxx","type":"agent.message","session_id":"sess_xxx","content":[{"type":"text","text":"Here is the analysis result."}],"processed_at":"2026-06-22T11:00:03Z"}

Event delta streaming example

When event_deltas[] is provided, the stream includes event_start and event_delta frames before the final buffered event:

id: evt_xxx
event: event_start
data: {"id":"evt_xxx","type":"event_start","session_id":"sess_xxx","event":{"id":"evt_xxx","type":"agent.message"}}

id: evt_xxx
event: event_delta
data: {"id":"evt_xxx","type":"event_delta","session_id":"sess_xxx","event_id":"evt_xxx","delta":{"type":"content_delta","index":0,"content":{"type":"text","text":"Here"}}}

Response fields

Field	Description
id	SSE event ID. Equals the Event ID.
event	Event type.
data	Filtered Forward Event JSON. Standard public events follow the Event type matrix documented by List Session Events; event delta stream frames follow Event delta streaming.

Errors

HTTP	Type	Code	Trigger
404	not_found_error	-	Last-Event-ID references an Event that does not exist or does not belong to this Session.
401	authentication_error	authentication_required	PAT invalid or expired.
404	not_found_error	session_not_found	Session does not exist.

Notes

• event_deltas[] is the recommended way to enable streaming; when this parameter is not provided, only standard public events are returned.
• incremental_streaming_enabled is a legacy streaming toggle retained for backward compatibility. If a Session was created with incremental_streaming_enabled=true, it uses legacy streaming and event_deltas[] will not take effect on that Session.
• Unknown Event types are forwarded as envelope-only events when available.
• include_thinking=false filters thinking events, legacy thinking deltas, and new stream agent.thinking event start signals and delta.content.type=thinking fragments.
• include_tool_calls=false filters tool-use events and legacy tool input/output deltas.

Related

Create a session

List session events