RoslynMcp

A Model Context Protocol (MCP) server that brings Roslyn code intelligence to AI agents.

Get It on NuGet

This project uses Roslynator, licensed under Apache 2.0.

Installation

dotnet tool install -g RoslynMcp

Update

dotnet tool update -g RoslynMcp

MCP config (OpenCode)

  "mcp": {
    "roslyn": {
      "type": "local",
      "command": [
        "roslynmcp"
      ]
    }
  }

What It Is

RoslynMcp is a .NET application that exposes the power of Roslyn (the .NET compiler platform) through the MCP protocol. It acts as a bridge between AI assistants and your C# codebase, enabling deep code understanding and analysis.

Why It Exists

Traditional AI code assistants often rely on simplistic pattern matching (grep/glob) which misses semantic context. RoslynMcp solves this by providing:

• Semantic understanding — It knows what your code means, not just what it says
• Symbol resolution — Understands types, methods, properties across your entire solution
• Call graph tracing — See how code flows through your system

Recommended Workflows

Choose the entry point based on what you already know.

%%{init: {"theme": "base", "themeVariables": { "background": "transparent" }}}%%
flowchart TD
    ls[load_solution]
    lp[load_project]
    lt[load_type]
    lm[load_member]
    fr[find_references]
    st[search_type]
    sm[search_member]
    df[diagnose_file]
    rt[run_tests]
    ls -->|projectPath| lp
    lp -->|typeSymbolId| lt
    lt -->|memberSymbolId| lm
    lt -->|typeSymbolId| fr
    st -->|typeSymbolId| lt
    sm -->|memberSymbolId| lm
    lm -->|memberSymbolId| fr
    ls -.-> st
    ls -.-> sm
    lm -.->|filePath from location| df
    df -.-> rt
    classDef tool fill:#1f2937,stroke:#9ca3af,color:#f9fafb;
    class ls,lp,lt,lm,fr,st,sm,df,rt tool;
    linkStyle default stroke:#9ca3af,stroke-width:1.5px;

This keeps navigation semantic and symbol-aware without relying on text-only search, while still giving you fast search and file-level validation when you need it.

The full tool descriptions can be found here