update-doc

Update project documentation after implementing new features, API endpoints, CLI commands, architectural changes, or workflow changes that affect how the project is understood, used, or maintained. Covers docs/ and README.md. Maintains Tables of Contents (up to h4). Handles new doc files by linking them from README.md. NEVER modifies CLAUDE.md, MEMORY.md, specs/, or docs/manual/. Do NOT use for internal refactors, small bug fixes, dependency bumps, test-only changes, or any change that does not affect usage, behavior, APIs, or conceptual understanding.