What problem does it solve? Understanding how an unfamiliar subsystem works requires hours of manual code reading. This Skill answers "how does X work" questions by exploring the codebase and producing a senior-engineer-level architectural explanation with a working mental model. ## Core Features & Use Cases - Complexity Assessment: Routes simple questions to a single-pass explainer and complex subsystem questions to parallel explorers plus a synthesizer. - Parallel Exploration: Decomposes broad questions into 2-4 exploration angles, each investigated by a read-only subagent that traces entry points, call chains, abstractions, and boundaries. - Structured Explanations: Synthesizes findings into sections covering Overview, Key Concepts, How It Works, Where Things Live, and Gotchas, with mermaid or ASCII diagrams where useful. - Use Case: Before modifying a payment processing flow spanning multiple services, ask how it works and receive a walkthrough of the trigger, step-by-step data flow, key files, and non-obvious pitfalls. ## Quick Start Ask how the authentication flow in this repository works and receive an architectural explanation of the subsystem.