Before you refactor an interface or estimate a sprint in unfamiliar code, this answers the questions static analysis tools don't: who actually depends on this module, what's the real blast radius if I change it, which files are the high-coupling chokepoints. It parses your repo into ast_nodes.json, then lets you query with five modes: file skeleton, reverse dependencies (who imports X), impact radius (upstream + downstream counts), hub analysis (most-depended-on modules), and directory-level summary. The who-imports and impact queries are the money shots when you're about to rename something or touch a core abstraction. Requires Python 3.10+ and produces hard numbers, not guesses. Works standalone or shares the .nexus-map structure with nexus-mapper if you need the full knowledge base later.
npx skills add https://github.com/haaaiawd/nexus-skills --skill nexus-query