Claude Code Hooks Guide 2026: Automate Your AI Coding Workflow
Claude Code hooks let you attach shell commands to specific moments in your AI coding session—like automatically formatting code or running tests every time Claude edits a file—without lifting a finger. CLAUDE.md is a project-level readme that tells Claude about your codebase upfront so it doesn't waste time re-learning your conventions each session. Together, these two features turn Claude Code from a conversational assistant into an automated coding pipeline.
MISSION OBJECTIVES
- 01Create a `.claude/` directory in your project root and add a `settings.json` file with a Prettier hook targeting the `Edit|Write` matcher using the exact config snippet below, then open a file and ask Claude to make a change to confirm auto-formatting fires.
- 02Write a `CLAUDE.md` file in your project root listing your build command, lint command, test command, and three key architectural decisions—keep it under 300 words—so Claude stops asking you to explain your stack at the start of each session.
- 03Install the `karanb192/claude-code-hooks` event-logger script (`event-logger.py`) from GitHub, run it against your next Claude session, and inspect the stdin JSON payloads to identify which of the 17–18 lifecycle events are most useful for your workflow.
CODE INTELLIGENCE
{
"hooks": [
{
"matcher": "Edit|Write",
"hooks": [
{
"type": "command",
"command": "prettier --write \"$CLAUDE_FILE_PATHS\""
}
]
}
]
}FIELD OPERATIONS
Auto-Test-on-Edit CI Pipeline Inside Claude Code
Configure a PostToolUse hook that triggers `npm test -- --testPathPattern=$CLAUDE_FILE_PATHS` every time Claude writes a file, then pipe failures back as a follow-up prompt so Claude iterates until tests pass—creating a tight local red-green-refactor loop without leaving the terminal.
Dangerous Command Blocker with Slack Alert
Build a PreToolUse hook that intercepts shell commands matching patterns like `rm -rf`, `DROP TABLE`, or `force push`, exits with a non-zero code to block execution, and calls a Slack webhook to notify the team—giving businesses an audit trail of blocked destructive actions during AI-assisted development sessions.
STRATEGIC APPLICATIONS
- →A software agency onboarding new developers can place a CLAUDE.md in every client repo with that client's linting rules, deployment commands, and forbidden patterns, ensuring Claude Code gives consistent, project-appropriate suggestions to every team member from day one without a senior engineer explaining the stack each time.
- →A SaaS company running multiple microservices can use Edit|Write hooks to auto-run TypeScript type checks and ESLint on every file Claude touches, catching type errors and style violations in real time and preventing broken code from ever reaching a pull request review.