how

How

Explore the codebase to answer "how does X work?" questions. Produce architectural explanations at the level of a senior engineer onboarding onto a subsystem, enough to build a working mental model, not so much that it reads like annotated source code.

Explorers and the explainer are subagents that inherit the session's model. They read and search, and they change nothing.

Assess complexity

If the scope is ambiguous, state your interpretation and explore. The operator can redirect.

• Simple (a single module, a small utility, a narrow question such as "how does function X work"): no explorers. One explainer explores and explains in a single pass. Go to "Explain directly".
• Complex (a subsystem spanning multiple files or services, a cross-cutting feature, a full architectural overview): spawn parallel explorers first, then hand off to the explainer. Go to "Explore".

When in doubt, take the simple path.

Explore, for a complex question

Decompose the question into 2 to 4 exploration angles, each a distinct slice of the subsystem. Spawn all explorers in a single message, so that they run concurrently, and go on only once every finding is back.

Each explorer gets the prompt in references/explorer-prompt.md with its angle filled in. Then go to "Synthesize".

Explain directly, for a simple question

Spawn one subagent that explores and explains in one pass.

Build its prompt from references/explainer-prompt.md without the explorer-findings section. Go to "Present".

Synthesize, for a complex question

Once all explorers have returned, spawn one subagent to synthesize their findings into one explanation.

Build its prompt from references/explainer-prompt.md with every explorer's findings filled in.

Present

Once the explainer's output is back, present it to the operator. Light edits for clarity or context from the conversation are fine. Do not substantially rewrite it.

Output format

The explanation uses the sections defined in references/explainer-prompt.md, dropping any that do not apply: Overview, Key concepts, How it works, Where things live, Gotchas.