Beta SDKs for the 2026-07-28 MCP Spec Release Candidate Are Here

The MCP protocol is about to undergo its biggest revision since launch. As you might’ve seen from our recent release candidate announcement, the new protocol revision goes stateless, removing the initialize handshake and the protocol-level session, and completing the plan we laid out in The Future of MCP Transports. If you’re building MCP servers, you can now scale them using a simple round-robin load balancer, removing the need to manage sticky sessions and to store shared sessions. For client developers, new patterns, like Multi Round-Trip Requests (MRTR) enable a whole new range of possibilities for server-to-client interactions. You can check out the full changelog to see what’s coming. ...

June 29, 2026 · 9 min · Felix Weinberger (TypeScript SDK Lead), Max Isbey (Python SDK Lead), Den Delimarsky (Lead Maintainer)

The 2026-07-28 MCP Specification Release Candidate

The release candidate for MCP 2026-07-28 is now available. It is the largest revision of the protocol since launch and delivers on the 2026 roadmap: a stateless core that scales on ordinary HTTP infrastructure extensions including server-rendered UIs through MCP Apps and long-running work through the Tasks extension authorization that aligns more closely with OAuth and OpenID Connect deployments a formal deprecation policy so the protocol can evolve without breaking what you’ve built, and many other changes. ...

May 21, 2026 · 9 min · David Soria Parra (Lead Maintainer), Den Delimarsky (Lead Maintainer)

One Year of MCP: November 2025 Spec Release

Today, MCP turns one year old. You can check out the original announcement blog post if you don’t believe us. It’s hard to imagine that a little open-source experiment, a protocol to provide context to models, became the de-facto standard for this very scenario in less than twelve months. But not only do we hit the first anniversary milestone today - we’re also releasing a brand-new MCP specification version. Before we get to the details of what’s new, let’s do a bit of a retrospective. ...

November 25, 2025 · 21 min · MCP Core Maintainers