Stop Background Task (Extension)

POST /agent/v1/sessions/{session_id}/background_tasks/{task_id}/stop● Supported

Request parameters

session_idstring必填
path: Session id (sesn_...), as returned by sessions.create or sessions.list. The same id is also accepted as the session_id query parameter on resource and thread calls, where it must equal the path value.
task_idstring必填
path: Background task id (task_...), as listed by sessions.background_tasks.list.

Returns

200

Own-face extension. No request body is required. Uses the same stop implementation as TaskStop: records stop_requested_at and signals the process group. Returns BackgroundTask with the same fields as the list operation. Until termination is observed, status may remain running with cancellable=false. An ended or unsupported task returns 409. Missing or inaccessible sessions or tasks return 404.

Errors follow the Anthropic error format (type / message / request_id) — see error codes

Response

HTTP 200

Current task after stop request

application/json

Name	Type	Description
id	string	Identifier of the object, as returned by the API; pass it in the path of follow-up calls on the same resource.
kind	string	Kind of background task: bash for a command started with run_in_background, monitor for a Monitor watch.
title	string	Short human-readable title of the task or object.
thread_id	string \| null	Execution thread the task belongs to; null for the primary thread.
status	string	Current lifecycle state.
started_at	string	RFC 3339 time at which the task started.
ended_at	string \| null	RFC 3339 time at which the task ended; null while it is running.
cancellable	boolean	Whether the task can still be stopped.
notified_at	string \| null	RFC 3339 time of the latest run that the task's notification started; null while no notification has been delivered.
trigger_count	integer \| null	For a monitor task, how many times its matches woke the session; null for other kinds or before the first notification.