The Model Context Protocol (MCP) has been evolving quickly. One of the most interesting changes in the latest MCP specification is the move toward a stateless protocol model . I recently updated my MCP currency converter server to work with the newer stateless behavior and the new split TypeScript SDK packages, particularly @modelcontextprotocol/server . In this article, I'll explain: What MCP sessions were doing What "stateless MCP" actually means Why the change matters for ...