Microsoft’s official C# SDK for implementing Mannequin Context Protocol (MCP) servers and purchasers has reached its 1.0 milestone launch. The replace brings full help for the 2025-11-25 model of the MCP Specification, highlighted by enhanced authorization server discovery and icon metadata for instruments, sources, and prompts.
MCP C# SDK 1.0 was unveiled March 5 and may be discovered on GitHub. The MCP C# SDK 1.0 launch represents a serious step ahead for constructing MCP servers and purchasers in .NET, based on Microsoft. Builders can use the SDK to implement safe authorization flows, construct wealthy software experiences with sampling, or deal with long-running operations, the corporate stated.
With authorization server discovery within the 2025-11-25 MCP specification, servers have 3 ways to show the Protected Useful resource Metadata (PRM) doc: by way of a “well-known” URL derived from the server’s MCP endpoint path, on the root well-known URL, and, as earlier than, by way of a URL within the useful resource metadata parameter of the WWW-Authentication header.
