This README was created using the C# MCP server project template. It demonstrates how you can easily create an MCP server using C# and publish it as a NuGet package.
The MCP server is built as a framework-dependent application and requires the .NET runtime to be installed on the target machine. The application is configured to roll-forward to the next highest major version of the runtime if one is available on the target machine. If an applicable .NET runtime is not available, the MCP server will not start. Consider building the MCP server as a self-contained application if you want to avoid this dependency.
See aka.ms/nuget/mcp/guide for the full guide.
Please note that this template is currently in an early preview stage. If you have feedback, please take a brief survey.
- Test the MCP server locally using the steps below.
- Update the package metadata in the .csproj file, in particular the
<PackageId>. - Update
.mcp/server.jsonto declare your MCP server's inputs.- See configuring inputs for more details.
- Pack the project using
dotnet pack.
The bin/Release directory will contain the package file (.nupkg), which can be published to NuGet.org.
To test this MCP server from source code (locally) without using a built MCP server package, you can configure your IDE to run the project directly using dotnet run.
{
"servers": {
"mcpserver": {
"type": "stdio",
"command": "dotnet",
"args": [
"run",
"--project",
"<PATH TO PROJECT DIRECTORY>"
]
}
}
}Once configured, you can ask Copilot Chat for a random number, for example, Give me 3 random numbers. It should prompt you to use the get_random_number tool on the mcpserver MCP server and show you the results.
- Run
dotnet pack -c Releaseto create the NuGet package - Publish to NuGet.org with
dotnet nuget push bin/Release/*.nupkg --api-key <your-api-key> --source https://api.nuget.org/v3/index.json
Once the MCP server package is published to NuGet.org, you can configure it in your preferred IDE. Both VS Code and Visual Studio use the dnx command to download and install the MCP server package from NuGet.org.
- VS Code: Create a
<WORKSPACE DIRECTORY>/.vscode/mcp.jsonfile - Visual Studio: Create a
<SOLUTION DIRECTORY>\.mcp.jsonfile
For both VS Code and Visual Studio, the configuration file uses the following server definition:
{
"servers": {
"mcpserver": {
"type": "stdio",
"command": "dnx",
"args": [
"<your package ID here>",
"--version",
"<your package version here>",
"--yes"
]
}
}
}.NET MCP servers use the ModelContextProtocol C# SDK. For more information about MCP:
Refer to the VS Code or Visual Studio documentation for more information on configuring and using MCP servers: