The MCP server accepts newer protocol versions

A client that requests an MCP protocol version newer than the server supports, such as 2026-07-28, now gets a working session at the server's newest version (2025-11-25). This applies to initialize and to the MCP-Protocol-Version header on later requests. Before, those later requests returned 400 Bad Request: Unsupported protocol version, so clients such as Claude's connectors could not connect. A malformed version, or one older than the server supports, still returns 400.