Structure codebases for AI agents with modular design

Cursor and Claude Code can ship working admin pages from a 200-component design system without manual coding, but only if the repo is structured for agent readability. Five structural properties—module boundaries, typed contracts, barrel exports, consistent naming, and small files—each roughly double what an agent can reliably do. The pattern works in any repo, not just OTF kits, and costs almost nothing to implement.