Updated
Updated · InfoWorld · Jul 29
Microsoft Ships MCP C# SDK 2.0 as 2026-07-28 Spec Makes HTTP Stateless
Updated
Updated · InfoWorld · Jul 29

Microsoft Ships MCP C# SDK 2.0 as 2026-07-28 Spec Makes HTTP Stateless

3 articles · Updated · InfoWorld · Jul 29

Summary

  • MCP C# SDK v2.0 now implements the 2026-07-28 MCP revision, with Microsoft calling it the protocol’s biggest overhaul since launch.
  • HttpServerTransportOptions.Stateless now defaults to true, replacing the 1.x default of stateful sessions and turning each MCP request into a self-describing HTTP POST.
  • Standardized headers such as Mcp-Method and Mcp-Name let load balancers, proxies, gateways and web application firewalls route MCP traffic without deep packet inspection.
  • MRTR support on both server and client enables multi-step interactions—such as user confirmation before a significant action—without a live session because continuity moves in the payload.
  • Microsoft said its next priority after spec compliance is end-to-end authentication and authorization, aiming for turnkey secure deployments built on closer OAuth and OpenID Connect alignment.

Insights

Is Microsoft’s MCP C# SDK v2.0 the moment AI tool servers become ordinary stateless web services?
How much easier will MCP be to scale and secure now that every request is self-describing and session-free?
Can MRTR deliver smooth multi-step AI tool workflows without bringing back the session complexity MCP is trying to escape?