[Utility] Guide for developing Claude Code hooks - shell commands that execute automatically in response to tool calls and notifications. Use this when users want to create, debug, or optimize hooks for automating workflows like linting, formatting, notifications, or custom validations. Supports PreToolUse, PostToolUse, Stop, SubagentStop, SessionStart, SessionEnd, UserPromptSubmit, PreCompact, Notification events.

[Code Quality] Identifies architectural hotspots: high-churn files, coupling issues, layer violations, and dependency tangles. Use to find systemic issues that cause repeated bugs or slow development.