Hooks — Workflow Automation

Teaching Claude Reflexes

In the last seven blocks, every action Claude took was something you explicitly asked for. “Add dark theme.” “Review K8s manifests.” “Generate a provisioning script.” That’s the conversational model — you ask, Claude does.

Hooks flip the script. Instead of you telling Claude what to do, you tell Claude what should always happen — automatically, every time, without you having to remember. “After every file edit, run Prettier.” “Before any edit to .env, stop and ask.” “When a session starts, show me the git status.”

Think of hooks as Claude’s reflexes. You don’t think about blinking — it just happens. Hooks are the same idea: actions that fire automatically at the right moment, so you can focus on the actual work instead of the ceremony around it.

What We’ll Cover

1. What hooks are — automated actions that fire at Claude Code lifecycle events
2. The four hook types — command, prompt, agent, and http
3. Event types — when hooks fire (before tools, after tools, session start, etc.)
4. Exit codes — how hooks control flow (proceed vs. block)
5. Hands-on hooks — auto-format, file protection, notifications, and confirmation prompts
6. Verbose mode — watching hooks fire in real time with Ctrl+O

Why This Block Matters

Every team has rules that live in people’s heads. “Don’t edit package-lock.json manually.” “Always run the linter before committing.” “Ping the team channel when a deploy finishes.” These rules get written in READMEs, mentioned in onboarding docs, and forgotten by the third week.

Hooks make these rules enforceable. Not by nagging people to follow them, but by making the right thing happen automatically. The file that shouldn’t be edited? Blocked at the hook level. The formatter that should run after every change? Fires without anyone thinking about it. The notification that a long task finished? Pops up on its own.

This is the difference between a convention and a constraint. Conventions rely on memory. Constraints rely on code.

Prerequisites

• Completed Blocks 0-7
• The ai-coderrank project open in Claude Code
• Basic familiarity with JSON configuration files
• macOS (for the notification hook example — Linux alternatives provided)

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