Documentation Index

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Request Cancellation is stabilized

Announcement that protocol-level request cancellation is now part of the stable ACP protocol.

Published: June 29, 2026

The Request Cancellation RFD has moved to Completed and the $/cancel_request notification is stabilized.

Either side can use the optional notification to request cancellation of an outstanding JSON-RPC request by ID. Implementations can return a valid partial result or the standard -32800 Request Cancelled error, while feature-specific mechanisms such as session/cancel remain available for richer semantics.

For the protocol documentation, see Cancellation.

Last updated Oct 08, 2026