Writing Hookify Rules

This walks you through creating Hookify rules, which are markdown files that watch for patterns in Claude's tool use and fire warnings or blocks when they match. You'd use it when you want to prevent dangerous bash commands, catch console.log statements before they ship, or enforce checklists before Claude stops working. The guide covers the YAML frontmatter structure, regex pattern writing, and the difference between simple pattern matches and multi-condition rules. It's thorough on the mechanics but light on philosophy. If you're setting up guardrails in a codebase where Claude might do something you'll regret later, this gives you the syntax and examples to write those rules quickly.

skills.sh installs: 168
GitHub stars: 476
last updated: Aug 21, 2026

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Install

$ npx -y skills add aiskillstore/marketplace --skill writing-hookify-rules --agent claude-code

Installs into .claude/skills of the current project.

Files

Writing Hookify Rules

Overview

Hookify rules are markdown files with YAML frontmatter that define patterns to watch for and messages to show when those patterns match. Rules are stored in .claude/hookify.{rule-name}.local.md files.

Rule File Format

Basic Structure

---
name: rule-identifier
enabled: true
event: bash|file|stop|prompt|all
pattern: regex-pattern-here
---

Message to show Claude when this rule triggers.
Can include markdown formatting, warnings, suggestions, etc.