A Roslyn-powered MCP server that gives Claude direct access to your C# and VB.NET codebase structure without reading source files. Exposes 28 tools for symbol lookup, call graph traversal, type hierarchy queries, and architectural fact extraction (HTTP endpoints, DI registrations, config keys, middleware). Builds a persistent semantic index from your .sln or .slnx file, then answers questions like "who calls this method" or "where is this config key used" in 200 tokens instead of 3,600. Handles cross-DLL references into NuGet packages with optional decompilation. Reach for this when you're working on medium to large C# projects and want Claude to navigate by semantic intent rather than grepping through thousands of lines.