Skill: codebase-exploration

Purpose

The default move in an unfamiliar repo is to start opening files — grep a symbol, read the hit, follow an import, read that, and keep going. By the time you understand the layout, you have pulled twenty files of source into the one context that has to do the actual work, and your attention is spread across all of it. Long context degrades attention non-uniformly — relevant facts buried in the middle of a bloated window get missed even when they are present.

This skill changes that: the orchestrator does not read source files to orient. It delegates 2-4 narrow, read-only recon slices to subagents, gets back a compact key-files map (path → one-line role), and only then reads the handful of files that actually matter — in a context that is still mostly empty. The recon cost is paid in throwaway subagent contexts; the main context stays clean for the work.

When to delegate vs. just look