claude-plugins-official/plugins/hookify/README.md

# 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

```bash
/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`:
```markdown
---
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`:
```markdown
---
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

```markdown
---
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

```markdown
---
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

```markdown
---
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:

```markdown
---
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:
```bash
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:**
```bash
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