efiadm/claude-code-hooks

Claude Code Hooks Setup

Configure PostToolUse hooks for real-time auto-linting as Claude Code edits files.

Purpose

Enable automatic linting after every file edit by Claude Code:

• PostToolUse hooks: Run after Edit or Write tool operations
• Auto-fix: Apply linter fixes automatically
• Multi-language: Support for JS/TS/Python/Ruby/Go/Rust

When to Invoke

Automatic (via hooks-setup orchestrator)

• After CLAUDE.md is created or modified
• During project initialization

Manual Invocation

• "Set up Claude Code hooks"
• "Enable auto-linting on file edits"
• "Configure PostToolUse hooks"
• "Run ESLint automatically after changes"

Setup Process

Step 1: Analyze CLAUDE.md

Identify:

1. Languages used in project
2. Linting tools (ESLint, Prettier, Black, etc.)
3. Package manager (for command execution)
4. Auto-fix capabilities

Step 2: Run Setup Script

python .claude/skills/claude-code-hooks/scripts/setup_claude_hooks.py

What the script does:

1. Parses CLAUDE.md for linting tools
2. Detects package manager
3. Generates PostToolUse hook configuration
4. Creates/updates .claude/settings.json

Step 3: Verify Installation

1. Edit a file with linting issues
2. Verify linter runs automatically
3. Check auto-fixes are applied

Hook Configuration

.claude/settings.json

{
  "description": "Auto-lint files after Claude Code edits",
  "hooks": {
    "PostToolUse": [
      {
        "matcher": "Edit|Write",
        "hooks": [
          {
            "type": "command",
            "command": "if [[ \"$CLAUDE_TOOL_FILE_PATH\" == *.ts ]]; then npx eslint \"$CLAUDE_TOOL_FILE_PATH\" --fix 2>/dev/null || true; fi"
          }
        ]
      }
    ]
  }
}

Language-Specific Patterns

JavaScript/TypeScript

npx eslint "$CLAUDE_TOOL_FILE_PATH" --fix 2>/dev/null || true

Python

black "$CLAUDE_TOOL_FILE_PATH" 2>/dev/null || true

Ruby

rubocop "$CLAUDE_TOOL_FILE_PATH" --auto-correct 2>/dev/null || true

Go

gofmt -w "$CLAUDE_TOOL_FILE_PATH" 2>/dev/null || true

Rust

rustfmt "$CLAUDE_TOOL_FILE_PATH" 2>/dev/null || true

Multi-Language Configuration

{
  "hooks": {
    "PostToolUse": [
      {
        "matcher": "Edit|Write",
        "hooks": [
          {
            "type": "command",
            "command": "if [[ \"$CLAUDE_TOOL_FILE_PATH\" == *.py ]]; then black \"$CLAUDE_TOOL_FILE_PATH\" 2>/dev/null || true; elif [[ \"$CLAUDE_TOOL_FILE_PATH\" == *.ts || \"$CLAUDE_TOOL_FILE_PATH\" == *.tsx ]]; then npx eslint \"$CLAUDE_TOOL_FILE_PATH\" --fix 2>/dev/null || true; fi"
          }
        ]
      }
    ]
  }
}

Best Practices

1. Graceful failure: Always use 2>/dev/null || true
2. Auto-fix when possible: Use --fix flags
3. Check file extensions: Use proper bash pattern matching
4. Project-level config: Use .claude/settings.json for teams
5. Test with CLAUDE_TOOL_FILE_PATH: Verify commands work

Customization

See references/claude-hook-patterns.md for:

• Advanced hook patterns
• Conditional execution
• Performance optimization
• Debugging hooks

Troubleshooting

Hooks not running

1. Check .claude/settings.json exists
2. Verify JSON syntax is valid
3. Test command manually with CLAUDE_TOOL_FILE_PATH

Linter not found

1. Ensure linter is in package.json
2. Check npx/pnpm exec path resolution
3. Install missing dependencies