What problem does it solve? When working with a dependency, inherited project, or open-source repo you did not write, READMEs and docs describe intent rather than actual behavior, leading to wrong-API usage and hallucinated signatures. This Skill pulls the real upstream source and maps it into a call graph so you read the files that actually matter. ## Core Features & Use Cases - Real Source Fetching: Uses opensrc to download the actual GitHub source tree behind npm, PyPI, or crates.io packages at the exact version you depend on. - Call Graph Mapping: Uses graphify to build a local AST-based call/containment graph with zero tokens, no LLM, and no API key, producing a queryable graph.json and a human-readable report. - Targeted Reading Workflow: Query symbols, call paths, and relationships with graphify explain/path/query before opening files, so you read twenty relevant files instead of two thousand. - Use Case: Before modifying an inherited codebase or depending on a library whose behavior matters, run opensrc path zod then graphify update on the result, query the graph for the symbols you care about, and read only those files. ## Quick Start Ask the agent to pull the real source of the library you are about to use with opensrc, map it with graphify, and explain how a specific function is called before you change any code.