MCP C# SDK — MCP Protocol

Official SDK for building MCP servers and clients in C#

Basic Information

What Is This Program?

This is the official SDK for developers who want to build MCP servers in C#. It abstracts MCP's core primitives (tools, resources, prompts) in a type-safe way.

This SDK runs on .NET 8 or later and supports both stdio and Streamable HTTP transports. You can naturally add MCP features to existing C# codebases.

What Problems Does It Solve?

• ('In C# projects', 'When you need to implement MCP servers and clients', 'Ensure protocol compliance with official primitives')
• ('Type safety', 'When you need to prevent incorrect protocol use at compile time', 'Catch mistakes early with the type system')
• ('Multiple transports', 'When you need to support both local stdio and remote HTTP', 'Choose the transport that fits your deployment environment')

Key Features

Server Implementation

Server API for registering tools, resources, and prompts

• Use case: Expose external tools through MCP
• Result: Type-safe server definitions
• Limitations: Requires learning the protocol

Client Implementation

Client API for connecting to MCP servers

• Use case: Call servers from agents
• Result: Connect through the standard protocol
• Limitations: Authentication configuration required

Transport Layer

Built-in stdio and Streamable HTTP transports

• Use case: Support both local and remote scenarios
• Result: Deploy without switching transports
• Limitations: Requires CORS and authentication for remote use

Installation and Execution

dotnet

Install with the C# package manager.

dotnet add package ModelContextProtocol

Real-World Usage Examples

Starting the Server

dotnet run

Run the MCP server over stdio.

Advantages and Limitations

Advantages

• Official MCP project, ensuring protocol compliance
• Idiomatic C# development patterns
• Multiple transport support

Considerations Before Use

• Requires installing the C# runtime
• Timing for 2026 specification support varies by SDK

Comparison with Similar Programs

Official Resources and Further Learning

• Official website — https://modelcontextprotocol.io/docs/sdk
• Official documentation / knowledge base — https://github.com/modelcontextprotocol/csharp-sdk-sdk
• Installation & Distribution — dotnet add package ModelContextProtocol
• Release notes — https://github.com/modelcontextprotocol/csharp-sdk-sdk/releases
• Source / development resources — https://github.com/modelcontextprotocol/csharp-sdk-sdk

Version and supported environment information was confirmed on the official site as of 2026-10-18. Installation commands may vary depending on your distribution and version, so also check the official installation documentation.

Actual Execution Screenshots

Synthetic example — not an actual execution result. The screen is a synthetic example and not an actual execution result.

!MCP C# SDK usage example

A server running in production

Source (HTML): https://games.aidebatehub.com/programs/mcp/protocol/csharp-sdk.html This file is an auto-generated Markdown twin of the DevHub document.