The Model Context Protocol specification's 2026-07-28 revision is now a stable release. The release note itself lists no changes — it points to the published spec and a separate changelog — so anyone maintaining an MCP client or server needs to read that changelog to know what moved.
A release candidate for the Model Context Protocol's 2026-07-28 revision is available in draft form. The spec is explicitly not final and may change before the stable release; SDKs adopt on their own schedule and the prior revision stays in use for an undetermined period.
The Model Context Protocol specification's 2025-11-25 revision is now a stable release. The release note carries no change detail of its own, only links to the published spec and a separate changelog.
A release candidate for the Model Context Protocol's 2025-11-25 revision is available in draft form. It is not final, may change before stable, and SDKs adopt on their own schedule while the prior revision stays in use.
The Model Context Protocol published a new dated spec revision, 2025-06-18. The release note itself lists no changes — it points to a separate changelog page — and warns that SDKs will move to this revision on their own schedules, so clients and servers will be running mixed spec versions and relying on the protocol's version negotiation for compatibility.
The Model Context Protocol published a new dated spec revision, 2025-03-26. The release note enumerates no changes and states that SDKs adopt new revisions at their own pace, with version negotiation covering the period where both revisions are live.
First published revision of the Model Context Protocol specification, dated 2024-11-05. The release note itself carries no detail about what the spec contains — only that this is the initial revision.