Claude Code Hooks Example

Security configuration for Claude Code using hooks and permissions.

Features

• File Permissions: Blocks access to sensitive directories and files (.env, venv/, pycache, .pyc)
• Bash Validation Hook: Pre-execution validation for Bash commands to prevent access to restricted paths
• Context Token Savings: Blocked directories contain thousands of generated/cached files that waste context tokens if accidentally read

Configuration

Settings defined in .claude/settings.local.json:

• Denied file patterns via permissions
• PreToolUse hook for Bash command validation

Validation script at .claude/scripts/validate-bash.sh blocks commands accessing:

• Environment files (.env)
• Build artifacts (build/, dist/) - often contain thousands of files
• Version control (.git/) - large binary objects
• Virtual environments (venv/) - thousands of dependency files
• Compiled files (.pyc)
• Cache directories (pycache)
• Data files (.csv, .log)

Usage

Copy .claude/ directory to your project to enforce similar security policies.