hookify

Hookify Plugin

Easily create custom hooks to prevent unwanted behaviors by analyzing conversation patterns or from explicit instructions.

Overview

The hookify plugin makes it simple to create hooks without editing complex hooks.json files. Instead, you create lightweight markdown configuration files that define patterns to watch for and messages to show when those patterns match.

Key features:

• 🎯 Analyze conversations to find unwanted behaviors automatically
• 📝 Simple markdown configuration files with YAML frontmatter
• 🔍 Regex pattern matching for powerful rules
• 🚀 No coding required - just describe the behavior
• 🔄 Easy enable/disable without restarting

Quick Start

1. Create Your First Rule

/hookify Warn me when I use rm -rf commands

This analyzes your request and creates .claude/hookify.warn-rm.local.md.

2. Test It Immediately

No restart needed! Rules take effect on the very next tool use.

Ask Claude to run a command that should trigger the rule:

Run rm -rf /tmp/test

You should see the warning message immediately!

Usage

Main Command: /hookify

With arguments:

/hookify Don't use console.log in TypeScript files

Creates a rule from your explicit instructions.

Without arguments:

/hookify

Analyzes recent conversation to find behaviors you've corrected or been frustrated by.

Helper Commands

List all rules:

/hookify:list

Configure rules interactively:

/hookify:configure

Enable/disable existing rules through an interactive interface.

Get help:

/hookify:help

Rule Configuration Format

Simple Rule (Single Pattern)

.claude/hookify.dangerous-rm.local.md:

---
name: block-dangerous-rm
enabled: true
event: bash
pattern: rm\s+-rf
action: block
---

⚠️ **Dangerous rm command detected!**

This command could delete important files. Please:
- Verify the path is correct
- Consider using a safer approach
- Make sure you have backups

Action field:

• warn: Shows warning but allows operation (default)
• block: Prevents operation from executing (PreToolUse) or stops session (Stop events)

Advanced Rule (Multiple Conditions)

.claude/hookify.sensitive-files.local.md:

---
name: warn-sensitive-files
enabled: true
event: file
action: warn
conditions:
  - field: file_path
    operator: regex_match
    pattern: \.env$|credentials|secrets
  - field: new_text
    operator: contains
    pattern: KEY
---

🔐 **Sensitive file edit detected!**

Ensure credentials are not hardcoded and file is in .gitignore.

All conditions must match for the rule to trigger.

Event Types

• bash: Triggers on Bash tool commands
• file: Triggers on Edit, Write, MultiEdit tools
• stop: Triggers when Claude wants to stop (for completion checks)
• prompt: Triggers on user prompt submission
• all: Triggers on all events

Pattern Syntax

Use Python regex syntax:

Pattern	Matches	Example
rm\s+-rf	rm -rf	rm -rf /tmp
console\.log\(	console.log(	console.log("test")
(eval|exec)\(	eval( or exec(	eval("code")
\.env$	files ending in .env	.env, .env.local
chmod\s+777	chmod 777	chmod 777 file.txt

Tips:

• Use \s for whitespace
• Escape special chars: \. for literal dot
• Use | for OR: (foo|bar)
• Use .* to match anything
• Set action: block for dangerous operations
• Set action: warn (or omit) for informational warnings

Examples

Example 1: Block Dangerous Commands

---
name: block-destructive-ops
enabled: true
event: bash
pattern: rm\s+-rf|dd\s+if=|mkfs|format
action: block
---

🛑 **Destructive operation detected!**

This command can cause data loss. Operation blocked for safety.
Please verify the exact path and use a safer approach.

This rule blocks the operation - Claude will not be allowed to execute these commands.

Example 2: Warn About Debug Code

---
name: warn-debug-code
enabled: true
event: file
pattern: console\.log\(|debugger;|print\(
action: warn
---

🐛 **Debug code detected**

Remember to remove debugging statements before committing.

This rule warns but allows - Claude sees the message but can still proceed.

Example 3: Require Tests Before Stopping

---
name: require-tests-run
enabled: false
event: stop
action: block
conditions:
  - field: transcript
    operator: not_contains
    pattern: npm test|pytest|cargo test
---

**Tests not detected in transcript!**

Before stopping, please run tests to verify your changes work correctly.

This blocks Claude from stopping if no test commands appear in the session transcript. Enable only when you want strict enforcement.

Advanced Usage

Multiple Conditions

Check multiple fields simultaneously:

---
name: api-key-in-typescript
enabled: true
event: file
conditions:
  - field: file_path
    operator: regex_match
    pattern: \.tsx?$
  - field: new_text
    operator: regex_match
    pattern: (API_KEY|SECRET|TOKEN)\s*=\s*["']
---

🔐 **Hardcoded credential in TypeScript!**

Use environment variables instead of hardcoded values.

Operators Reference

• regex_match: Pattern must match (most common)
• contains: String must contain pattern
• equals: Exact string match
• not_contains: String must NOT contain pattern
• starts_with: String starts with pattern
• ends_with: String ends with pattern

Field Reference

For bash events:

• command: The bash command string

For file events:

• file_path: Path to file being edited
• new_text: New content being added (Edit, Write)
• old_text: Old content being replaced (Edit only)
• content: File content (Write only)

For prompt events:

• user_prompt: The user's submitted prompt text

For stop events:

• Use general matching on session state

Management

Enable/Disable Rules

Temporarily disable: Edit the .local.md file and set enabled: false

Re-enable: Set enabled: true

Or use interactive tool:

/hookify:configure

Delete Rules

Simply delete the .local.md file:

rm .claude/hookify.my-rule.local.md

View All Rules

/hookify:list

Installation

This plugin is part of the Claude Code Marketplace. It should be auto-discovered when the marketplace is installed.

Manual testing:

cc --plugin-dir /path/to/hookify

Requirements

• Python 3.7+
• No external dependencies (uses stdlib only)

Troubleshooting

Rule not triggering:

1. Check rule file exists in .claude/ directory (in project root, not plugin directory)
2. Verify enabled: true in frontmatter
3. Test regex pattern separately
4. Rules should work immediately - no restart needed
5. Try /hookify:list to see if rule is loaded

Import errors:

• Ensure Python 3 is available: python3 --version
• Check hookify plugin is installed

Pattern not matching:

• Test regex: python3 -c "import re; print(re.search(r'pattern', 'text'))"
• Use unquoted patterns in YAML to avoid escaping issues
• Start simple, then add complexity

Hook seems slow:

• Keep patterns simple (avoid complex regex)
• Use specific event types (bash, file) instead of "all"
• Limit number of active rules

Contributing

Found a useful rule pattern? Consider sharing example files via PR!

Future Enhancements

• Severity levels (error/warning/info distinctions)
• Rule templates library
• Interactive pattern builder
• Hook testing utilities
• JSON format support (in addition to markdown)

License

MIT License