Anthropic releases MCP protocol version 5, switching to stateless core

Anthropic released version 5 of its Model Context Protocol (MCP) yesterday, calling it the biggest overhaul since the protocol launched. MCP is an open standard that helps large language models talk to outside data and tools. The biggest change is moving from a two-way stateful connection to a fully stateless core. No more handshake or session IDs. Each request is now independent and can go to any server, making it work well with serverless setups like AWS Lambda and Cloudflare Workers. The new version also adds a framework for extensions, including MCP Apps and Tasks, so developers can add interactive features and long-running tasks. For security, it now supports OAuth 2.0 and OIDC, letting MCP servers connect to enterprise systems like Entra or Okta.