code-review-graph is a local-first open-source tool that parses a codebase with Tree-sitter into a graph of functions, classes, imports, calls and test coverage, then serves compact review context over MCP so AI coding assistants read only the files a change actually touches. The project reports a median ~63x per-question token reduction versus a whole-corpus baseline across 6 open-source repositories (range 35x–358x), a ~40-second cold index of a ~3,000-file repo, and ~2.5 seconds to incrementally re-index a two-file edit. It also ships a GitHub Action that posts one sticky, risk-scored PR comment with affected execution flows and test gaps, optionally as a merge gate.