MSBuild Project Graph MCP Server

Pre-build static analysis of MSBuild solutions for LLM-powered coding assistants. Analyze project dependencies, detect build issues, inspect shared imports, and compare configurations — all through natural language, before building.

No existing MCP server provides pre-build project graph analysis. This fills that gap.

What It Does

Ask your AI assistant natural questions about your .NET/C++ solution:

• "Show me the dependency graph for this solution" → Full DAG with topological sort
• "Are there any TFM mismatches?" → Finds net6.0 projects referencing net8.0 libraries
• "What does Directory.Build.props affect?" → Shows all projects importing each shared file
• "Compare Debug vs Release" → Property and package reference differences
• "Where does LangVersion come from?" → Traces to Directory.Build.props line 3

Tools

Supported Clients

✅ Works with

❌ Not supported

Quick Start

Install

dotnet tool install -g MsBuildGraphMcp

Configure

Claude Desktop — add to %APPDATA%\Claude\claude_desktop_config.json:

{
  "mcpServers": {
    "msbuild-graph": {
      "command": "msbuild-graph-mcp"
    }
  }
}

Claude Code:

claude mcp add msbuild-graph -- msbuild-graph-mcp

VS Code — add to .vscode/mcp.json:

{
  "servers": {
    "msbuild-graph": {
      "type": "stdio",
      "command": "msbuild-graph-mcp"
    }
  }
}

Cursor — add to .cursor/mcp.json:

{
  "mcpServers": {
    "msbuild-graph": {
      "command": "msbuild-graph-mcp"
    }
  }
}

Requirements

• .NET SDK 8.0+ (or Visual Studio 2022+)
• Windows (MSBuildLocator discovers VS/.NET SDK installations)

Example Output

get_project_graph

{
  "metrics": {
    "nodeCount": 4,
    "edgeCount": 3,
    "uniqueProjectCount": 4,
    "maxDepth": 2,
    "constructionTimeMs": 297
  },
  "projects": [
    {
      "name": "WebApp",
      "targetFrameworks": ["net8.0"],
      "outputType": "Exe",
      "isRoot": true,
      "references": ["DataLib\\DataLib.csproj", "CoreLib\\CoreLib.csproj"]
    }
  ],
  "topologicalOrder": [
    "CoreLib\\CoreLib.csproj",
    "DataLib\\DataLib.csproj",
    "WebApp\\WebApp.csproj"
  ]
}

detect_build_issues

{
  "totalIssues": 2,
  "frameworkMismatches": [{
    "project": "OldApp.csproj",
    "projectTfm": "net6.0",
    "dependency": "NewLib.csproj",
    "dependencyTfm": "net8.0",
    "reason": "net6.0 cannot consume net8.0"
  }],
  "orphanProjects": [{
    "name": "UnusedLib",
    "reason": "Library with no referencing projects"
  }]
}

Features

• Pre-build analysis — no build required, evaluates MSBuild project files directly
• .sln / .slnx / .slnf — supports all solution formats including the new .slnx (VS 17.10+)
• Multi-targeting aware — correctly handles TargetFrameworks (plural) with outer/inner build deduplication
• TFM compatibility — NuGet.Frameworks-based checking (net8.0-windows vs net8.0, netstandard2.0 vs net48, etc.)
• Property source tracking — shows which file and line number defined each MSBuild property
• Configuration diffing — compares any two configurations (Debug/Release, custom configs)
• Circular dependency detection — catches both MSB4251 and CircularDependencyException
• Shared import discovery — identifies Directory.Build.props, Directory.Build.targets, Directory.Packages.props
• CPM detection — recognizes Central Package Management (ManagePackageVersionsCentrally)

Security

All tools are read-only — no builds are triggered, no files are modified.

Important: MSBuild property functions execute during evaluation (by design). Functions like $([System.IO.File]::ReadAllText(...)) run when a project is loaded. Only analyze projects you trust.

Architecture

┌──────────────────┐     stdio (JSON-RPC)   ┌─────────────────────┐
│ Claude / Copilot │◄──────────────────────►│ msbuild-graph-mcp   │
│ VS Code / Cursor │                        │                     │
└──────────────────┘                        │ MSBuildLocator      │
                                            │ ► ProjectGraph      │
                                            │ ► ProjectCollection │
                                            │ ► SolutionPersist   │
                                            └─────────────────────┘

Key architectural decisions:

• MSBuildLocator JIT trap pattern — RegisterInstance() in Main(), MSBuild types only in [NoInlining] method
• EvaluationContext.Shared via ProjectInstanceFactoryFunc — 2-5x speedup for large solutions
• Parallelism capped at 8 — prevents memory exhaustion on high-core machines
• Microsoft.Build 17.13.9 with ExcludeAssets="runtime" — avoids 17.14.8 dependency publishing bug

Testing

333 tests across 35 test files, sourced from 5 rounds of internet research covering 20+ sources:

dotnet test tests/MsBuildGraphMcp.Tests/
# Passed! - Failed: 0, Passed: 333, Skipped: 0, Total: 333, Duration: 12s

Test categories: validation, core tools, TFM compatibility, security (OWASP/CVE), solution formats, production resilience, concurrency, path edge cases, JSON serialization, real-world scenarios.

8 production bugs found and fixed during testing.

Complementary Tools

This server provides pre-build analysis. For post-build analysis (requires a completed build), see:

• BinlogInsights.Mcp — 26 MCP tools + 13 CLI commands for MSBuild binary log analysis (build times, errors, performance, analyzers)
• baronfel/mcp-binlog-tool — MSBuild binary log analysis (build times, errors, targets)

Contributing

See CONTRIBUTING.md for guidelines.

License

MIT - FlorinVica