Stateless MCP Removes Session Affinity for AWS Server Deployments

AWS outlined how the latest Model Context Protocol spec makes remote MCP servers stateless by removing the initialize/initialized handshake and the Mcp-Session-Id header. Requests can now be routed to any server instance behind a standard load balancer, simplifying horizontal scaling and enabling AWS Lambda deployments.

• Initialize/initialized handshake and Mcp-Session-Id header removed
• Requests can reach any instance behind a standard load balancer
• New Mcp-Method and Mcp-Name headers enable gateway routing and throttling
• Stream resumability removed, raising the importance of idempotency