What problem does it solve? Agents and developers often act on a codebase without verified context, leading to wrong assumptions about entry points, data flow, and module boundaries. This Skill builds a trustworthy, citation-backed map of a codebase or a single feature slice so downstream planning, implementation, and review work from facts instead of guesses. ## Core Features & Use Cases - Stack Detection: Reads dependency manifests (go.mod, package.json, pyproject.toml, Cargo.toml, and more) to confirm languages, frameworks, and versions before making any claim. - End-to-End Code-Flow Tracing: Follows call chains from entry points through every abstraction layer down to where data is persisted or leaves the process, recording each hop as file:line references. - Architecture Analysis: Documents module boundaries, ownership, dependency direction, seams, and deep versus shallow modules using a shared vocabulary downstream skills can reuse. - Use Case: Before planning a change to an API's request validation, a planning skill calls this Skill to map the handler entry point, the service seam, and the persistence boundary, receiving a cited report with an essential-files list. ## Quick Start Ask the agent to explore how authentication requests flow through this repository and report the entry points, seams, and essential files with file:line citations.