Azure MCP Server migrates to the 2026-07-28 stateless protocol in prerelease, requiring routing headers on every POST

Microsoft's Azure MCP Server migrated to the stateless 2026-07-28 protocol in prerelease 3.0.0-beta.30, published July 28, the day the revision landed. The changelog entry is explicit about the wire contract: HTTP clients using the new protocol must include the Mcp-Method and Mcp-Name routing headers on every POST request, while clients on the previous 2025-11-25 protocol are unaffected because the server auto-negotiates backward compatibility. The migration is built on the C# SDK at 2.0.0-preview.1.

The release page puts the server's individual tool count at 427 and lists its distribution channels: Azure.Mcp on NuGet, @azure/mcp on npm, msmcp-azure on PyPI, and .mcpb bundles. A follow-up prerelease, 3.0.0-beta.31, landed July 31.

The framing that matters for the tracker: this migration shipped in a beta prerelease, not a stable release, so it records as migrated-in-prerelease rather than a stable adoption milestone. The stable 3.0.0 will be the cleaner marker when it arrives.