code-graph-mcp

A high-performance code knowledge graph server implementing the Model Context Protocol (MCP). Indexes codebases into a structured AST knowledge graph with semantic search, call graph traversal, and HTTP route tracing — designed to give AI coding assistants deep, structured understanding of your code.

• Multi-language parsing — Tree-sitter AST extraction for TypeScript, JavaScript, Go, Python, Rust, Java, C, C++, HTML, CSS
• Semantic code search — Hybrid BM25 full-text + vector semantic search with Reciprocal Rank Fusion (RRF), powered by sqlite-vec
• Call graph traversal — Recursive CTE queries to trace callers/callees with cycle detection
• HTTP route tracing — Map route paths to backend handler functions (Express, Flask/FastAPI, Go)
• Impact analysis — Determine the blast radius of code changes by tracing all dependents
• Incremental indexing — Merkle tree change detection with file system watcher for real-time updates
• Context compression — Token-aware snippet extraction for LLM context windows (L0→full code, L1→summaries, L2→file groups, L3→directory overview)
• Embedding model — Optional local embedding via Candle (feature-gated embed-model)
• MCP protocol — JSON-RPC 2.0 over stdio, plug-and-play with Claude Code, Cursor, Windsurf, and other MCP clients
• Claude Code Plugin — First-class plugin with slash commands (/understand, /trace, /impact), agents, skills, auto-indexing hooks, StatusLine integration, and self-updating

Unlike naive full-text search or simple AST dumps, code-graph-mcp builds a structured knowledge graph that understands the relationships between symbols across your entire codebase.

BLAKE3 Merkle tree tracks every file's content hash. On re-index, only changed files are re-parsed — unchanged directory subtrees are skipped entirely via mtime cache. When a function signatur