Cancel Run

Cancel an active workflow run.

Immediately marks the run as cancelled and stops any further processing. In-flight work at the current node may be abandoned mid-execution. The operation is idempotent: cancelling an already-cancelled run returns the run unchanged without error.

Runs already in a terminal state (completed, failed, or cancelled) are returned unchanged. Concurrent terminalization is also treated as an idempotent success; a still-active compare-and-swap loser returns 409.

Unlike pause, cancel is permanent — a cancelled run cannot be resumed. Use pause if you intend to continue the run later.

Requires at least editor role in the workspace; viewers cannot cancel runs.