Hooks

Ultracite can automatically format and fix code after AI coding assistants make edits through editor hooks. This ensures all AI-generated code adheres to your project's standards without manual intervention.

The hooks work alongside Biome's linting and formatting. After an AI coding assistant edits a file, the hook automatically runs npx ultracite fix to format and fix auto-fixable linting issues. This dual approach ensures both intelligent code generation (through AI rules) and automated code quality (through hooks).

Note: Hooks are separate from AI coding rules. The --agents flag configures AI coding rules, while the --hooks flag sets up automatic formatting after file edits.

Setup

Automatic Setup

When you run npx ultracite init, you'll be prompted to select which editor hooks you want to enable:

? Which agent hooks do you want to enable (optional)?
  ◯ Cursor
  ◯ Claude Code

This will create the relevant hook configuration file in your project directory.

Manual Setup

If you want to manually set things up or add hooks after initialization, run:

npx ultracite init --hooks cursor,claude

Alternatively, you can manually create or edit the hook configuration files in your project directory and add the appropriate hook command.

Supported Editors

How It Works

1. Automatic Execution: After the AI agent edits a file, the hook automatically runs npx ultracite fix
2. Code Formatting: Ultracite formats the edited code according to your Biome configuration
3. Linting Fixes: Auto-fixable linting issues are resolved automatically
4. Seamless Integration: The process happens transparently without interrupting your workflow

Benefits

Using Ultracite editor hooks provides several advantages:

• Consistency: All AI-generated code is automatically formatted to match your style
• Quality: Linting issues are fixed immediately after code generation
• Efficiency: No need to manually run formatters or linters after AI edits
• Standards: Ensures AI-generated code always adheres to project standards
• Clean Commits: Code is properly formatted before you even review it

Customization

Ultracite intelligently merges with existing hook configurations:

• Preserves existing hooks: All existing hooks and their commands remain intact
• Avoids duplicates: If Ultracite is already configured, it won't be added again
• Non-destructive: Your existing hook configuration structure is maintained

You can also customize the hook behavior by modifying the hook configuration files directly if you need different formatting commands or additional post-edit actions.