MCP goes stateless on July 28 — delete your session store and route on Mcp-Method

Model Context Protocol Blog·high signal

The 2026-07-28 MCP release candidate removes the session concept from the protocol layer entirely: the initialize/initialized handshake and the Mcp-Session-Id header are gone, and protocol version, client identity, and capabilities now travel in a `_meta` object on every request. Any server instance can serve any request, so a remote MCP server runs behind a plain round-robin load balancer with no sticky sessions or shared session store. Clients may cache `tools/list` responses for as long as the server's `ttlMs` permits, and hosts route on the new `Mcp-Method` header.