On July 28, the Model Context Protocol project shipped a new spec revision, 2026-07-28. I run backend engineering at GoodBarber, and our public MCP server is a live production surface: real apps, real content, real push notifications. So for us a new revision is not a changelog to skim on a Friday. It is a migration with our name on it.
We have just brought the server up to the new revision. This post is three things: the operator's cut of what changed, what upgrading a public server actually involves, and the thing we found in our logs while checking the work. The last one is the reason I'm writing.
The operator's cut of 2026-07-28
The headline is the stateless core. MCP grew up as a stateful, bidirectional protocol: an initialize handshake, a negotiated session, an Mcp-Session-Id header to carry it all. The new revision retires that entirely. Every request now self-describes in _meta: protocol version, client identity, capabilities. The practical consequence is the one server operators have wanted since day one: you can put an MCP server behind a plain round-robin load balancer with no shared session storage. If you have ever kept session affinity alive with duct tape, you know exactly which muscle just relaxed.
