MCP .NET Implementation

Add the server and/or client packages to your .NET project. The Server package is needed to build an MCP server; the Client package is needed to connect to one.

dotnet add package Mcp.Net.Server
dotnet add package Mcp.Net.Client

Use the McpServerBuilder to register tools and select a transport. The following creates a stdio server with a single calculator tool suitable for Claude Desktop integration.

var builder = new McpServerBuilder()
    .WithName("MyServer")
    .UseStdioTransport();

builder.AddTool("multiply", "Multiplies two numbers",
    (double a, double b) => a * b);

await builder.Build().RunAsync();

Clone the repository and run the included SimpleServer example to verify your environment works before writing custom code.

git clone https://github.com/SamFold/Mcp.Net.git
cd Mcp.Net
dotnet run --project Mcp.Net.Examples.SimpleServer/Mcp.Net.Examples.SimpleServer.csproj

For SSE/HTTP transport, configure host, port, and scheme either via appsettings.json or environment variables. These are only needed if you are not using stdio.

{
  "Server": {
    "Port": 8080,
    "Hostname": "0.0.0.0",
    "Scheme": "http"
  }
}

Add the compiled .NET server binary to claude_desktop_config.json. Build your project first with `dotnet publish`, then reference the output executable.

{
  "mcpServers": {
    "mcp-net-example": {
      "command": "/path/to/publish/MyMcpServer",
      "args": []
    }
  }
}