Mirror of https://github.com/modelcontextprotocol/csharp-sdk — The official C# SDK for Model Context Protocol servers and clients. Maintained in collaboration with Microsoft.
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Stephen Halter 9df7640172
Reject mismatched initialize protocol versions (#1724)
Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>
2026-07-23 11:45:28 -07:00
.config Bump docfx from 2.78.4 to 2.78.5 (#1408) 2026-03-02 09:17:42 -05:00
.devcontainer Fix dev container configuration to work in codespaces (#1555) 2026-05-07 04:43:44 -07:00
.github Update package READMEs as part of the release process (#1683) 2026-07-07 15:13:32 -04:00
docs Implement RFC 9207 issuer validation in ClientOAuthProvider (#1605) 2026-07-23 08:01:22 -07:00
samples Implement RFC 9207 issuer validation in ClientOAuthProvider (#1605) 2026-07-23 08:01:22 -07:00
src Reject mismatched initialize protocol versions (#1724) 2026-07-23 11:45:28 -07:00
tests Reject mismatched initialize protocol versions (#1724) 2026-07-23 11:45:28 -07:00
.editorconfig style: (#746) 2025-09-02 18:34:17 +03:00
.gitattributes Add gitattributes (#98) 2025-03-25 18:57:01 -07:00
.gitignore Implementation for SEP-2243 Http Standardization (#1553) 2026-05-14 15:39:37 -07:00
CONTRIBUTING.md Add testing guidelines, update copilot instructions for tests (#1507) 2026-04-07 09:05:28 -07:00
Directory.Build.props Skip .NET Framework tests on non-Windows platforms (#1226) 2026-01-30 14:56:24 -08:00
Directory.Packages.props Implement SEP-2663 Tasks Extension (#1579) 2026-06-11 13:10:45 -07:00
global.json Revert "Update to MTP (#958)" (#1011) 2025-11-21 14:53:16 -08:00
LICENSE Release v1.1.0 (#1411) 2026-03-06 12:52:11 -08:00
logo.png Add Directory.Build.props, apply CPM, use NB.GitVersioning, update package publishing 2025-03-19 17:27:18 +02:00
Makefile Add AOT compatibility publish test (#1246) 2026-02-09 22:00:12 +02:00
ModelContextProtocol.slnx Extract Tasks into the ModelContextProtocol.Extensions.Tasks extension package (#1693) 2026-07-14 18:53:58 -04:00
nuget.config Fix nuget config 2025-03-19 15:12:55 -04:00
Open.snk Add strong naming (#49) 2025-03-21 17:51:05 +00:00
package-lock.json Re-enable http-custom-headers conformance scenario (#1655) (#1691) 2026-07-10 10:49:24 -07:00
package.json Re-enable http-custom-headers conformance scenario (#1655) (#1691) 2026-07-10 10:49:24 -07:00
README.md Release v2.0.0-preview.3 (#1706) 2026-07-14 20:21:31 -04:00
SECURITY.md Update SECURITY.md to use GitHub Security Advisories (#1306) 2026-02-18 15:41:14 -08:00
THIRD-PARTY-NOTICES.txt Add McpServer/ClientResource{Template} and friends (#391) 2025-05-09 18:21:11 -04:00

MCP C# SDK

NuGet version

The official C# SDK for the Model Context Protocol, enabling .NET applications, services, and libraries to implement and interact with MCP clients and servers. Please visit the API documentation for more details on available functionality.

Packages

The SDK packages are:

  • ModelContextProtocol.Core NuGet version - For projects that only need to use the client or low-level server APIs and want the minimum number of dependencies.

  • ModelContextProtocol NuGet version - The main package with hosting and dependency injection extensions. References ModelContextProtocol.Core. This is the right fit for most projects that don't need HTTP server capabilities.

  • ModelContextProtocol.AspNetCore NuGet version - The library for HTTP-based MCP servers. References ModelContextProtocol.

  • ModelContextProtocol.Extensions.Apps NuGet version - MCP Apps extension for building interactive UI applications that render inside MCP hosts.

  • ModelContextProtocol.Extensions.Tasks NuGet version - MCP Tasks extension for running long-running tool invocations asynchronously with status polling and input requests.

Getting Started

To get started, see the Getting Started guide in the conceptual documentation for installation instructions, package-selection guidance, and complete examples for both clients and servers.

You can also browse the samples directory and the API documentation for more details on available functionality.

About MCP

The Model Context Protocol (MCP) is an open protocol that standardizes how applications provide context to Large Language Models (LLMs). It enables secure integration between LLMs and various data sources and tools.

For more information about MCP:

Cross-Application Access (Identity Assertion Authorization Grant flow)

The SDK provides support for the Identity Assertion Authorization Grant flow via IdentityAssertionGrantProvider. See the Cross-Application Access section in the transport docs for full usage details.

License

This project is licensed under the Apache License 2.0.