explain-codebase

# Explain Codebase ## When to use Invoke this skill when onboarding to a codebase, investigating a subsystem, or locating where a change should be made. ## Steps 1. Map the entry points and the high-level modules from the directory layout. 2. Trace one concrete flow end to end (request, build, job) to anchor understanding. 3. Note the key abstractions, data structures, and external dependencies. 4. Identify the files most relevant to the user's question. 5. Produce a layered summary: what it does, how it works, where to start. ## Examples - "Explain how authentication works in this repo" - "Walk me through the request lifecycle" ## References Prefer file:line references and small diagrams over prose; stop before guessing behaviour you have not verified.