roslyn

This Roslyn-based MCP server exposes C# code analysis capabilities via the MCP protocol. It leverages the Roslyn compiler platform to validate C# files, locate symbol usages across a project, and analyze code within the full project context, including support for Microsoft code analyzers. Two primary tools are exposed: ValidateFile for syntax, semantic, and analyzer checks, and FindUsages to locate all references to a symbol at a given position. To use it, configure an MCP client to connect via standard I/O (stdio) to the server (as shown in the example config), then issue commands like ValidateFile and FindUsages with the appropriate parameters. The server runs a .NET project; running dotnet run will start the MCP server process, which listens for MCP commands over stdio.

Prerequisites:

• .NET SDK (compatible with Roslyn and the target project)
• MSBuild tools (often included with the .NET SDK)
• NuGet packages for Roslyn analyzers (typically restored automatically via the project)

Installation steps:

1. Clone or download the repository containing the Roslyn MCP server.
2. Ensure you have a valid RoslynMCP.csproj path as referenced in the README example.
3. Restore NuGet packages: dotnet restore
4. Build the project (optional but recommended): dotnet build
5. Run the server (from the repository or with the configured project path): dotnet run --project RoslynMCP/RoslynMCP/RoslynMCP/RoslynMCP.csproj
6. Connect an MCP client using the stdio protocol and issue commands like ValidateFile and FindUsages.

Notes and tips:

• The server uses Microsoft.CodeAnalysis (Roslyn) to perform code analysis and analyzers; ensure your project includes any required analyzers via NuGet.
• The example config uses an absolute path to RoslynMCP.csproj; adjust the path to your environment if needed.
• If you encounter client-server communication issues, verify the MCP protocol version compatibility and that the server process is running and listening on stdio.
• You can customize or extend the MCP server by integrating additional Roslyn capabilities (e.g., additional analyzers or code fixes) as needed.
• Ensure your .NET project references the necessary Roslyn packages for full diagnostics and analyzer support.