What is a matcher in a Claude Code hook?

A matcher is a string pattern (like 'Edit|Write') used to specify exactly which tool executions should trigger a particular hook.

How do hooks receive data from Claude?

Hooks receive data as a JSON object via standard input (stdin), containing details like the tool name, input parameters, and current working directory.

Where should I store my hook scripts?

It is recommended to store complex scripts in a .claude/hooks/ directory within your project or your user home directory for easy reference.

What are Claude Code Hooks?

They are specialized event listeners that trigger scripts or commands at specific points in Claude Code's execution lifecycle, such as before or after a tool is used.

Can I use hooks to prevent Claude from running certain commands?

Yes, using the PreToolUse hook, you can inspect tool inputs and set a permission decision to 'deny' based on your custom logic.

Claude Code Hooks

Name: Claude Code Hooks
Author: bendrucker

bybendrucker

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Productivity & Workflow

Automates and customizes Claude Code behavior through lifecycle event triggers and custom script integration.

About

The Claude Code Hooks skill provides a comprehensive framework for extending Claude's capabilities during its task execution lifecycle. It enables developers to implement automated testing, linting, input validation, and result processing at critical stages such as PreToolUse and PostToolUse. Whether you need to enforce security policies by blocking specific tool calls or enhance output by automatically formatting code with external utilities, this skill serves as the definitive guide and toolset for creating robust, event-driven workflows within the Claude Code environment.

Key Features

Configure lifecycle triggers including PreToolUse, PostToolUse, and UserPromptSubmit
5 GitHub stars
Control tool execution permissions and modify inputs dynamically
Implement pattern-based matchers for specific tools or MCP functions
Troubleshoot and debug hook failures using standard JSON protocols
Automate code quality checks like formatting and linting after file edits

Use Cases

Running unit tests or linters automatically before Claude commits a file change
Adding project-specific context to user prompts before they are processed by the AI
Enforcing security constraints by denying specific bash commands or file access

About

Key Features

Configure lifecycle triggers including PreToolUse, PostToolUse, and UserPromptSubmit
5 GitHub stars
Control tool execution permissions and modify inputs dynamically
Implement pattern-based matchers for specific tools or MCP functions
Troubleshoot and debug hook failures using standard JSON protocols
Automate code quality checks like formatting and linting after file edits

Use Cases

Running unit tests or linters automatically before Claude commits a file change
Adding project-specific context to user prompts before they are processed by the AI
Enforcing security constraints by denying specific bash commands or file access