Specification

The 2026-07-28 revision of the Model Context Protocol specification is now available in stable form on the official MCP website, with a detailed changelog listing the changes from the prior revision.

The Model Context Protocol 2026-07-28 revision is available as a release candidate in draft form, with a detailed changelog on the specification site. The spec is not final and may change before release, and SDKs will adopt the version at their own pace.

The 2025-11-25 revision of the Model Context Protocol specification is now a stable release, published on the official MCP website. A detailed changelog accompanies the revision.

The Model Context Protocol 2025-11-25 revision is available as a release candidate in draft form, with a draft changelog detailing the changes. The spec is not final and may change before release; clients and servers use version negotiation to determine which protocol version is in use.

The Model Context Protocol publishes the initial 2025-06-18 revision of the specification, with a detailed changelog hosted on modelcontextprotocol.io. SDKs will adopt the version at their own pace, and version negotiation between clients and servers permits backwards and forwards compatibility.

The 2025-03-26 revision of the Model Context Protocol specification is released. SDKs adopt revisions at their own pace, and the spec defines client-server version negotiation for backwards and forwards compatibility.

The 2024-11-05 revision of the Model Context Protocol is finalized, rolling up all backwards compatible changes made since the initial 2024-11-05 release.

The Model Context Protocol publishes its initial 2024-11-05 specification revision.

Final update to version 2024-10-07 of the MCP specification.