File Watcher

Use Claude Code's FileChanged and CwdChanged hooks to create reactive workflows that respond to file system changes.

Trigger

Use when:

• Setting up auto-reload for config changes
• Watching for dependency updates
• Monitoring build output
• Creating reactive development workflows

How File Watching Works

Claude Code's SessionStart and CwdChanged hooks support returning watchPaths to register file watchers. The current cwd-changed.js script focuses on env injection; to add watch registration, your hook script must output this JSON structure: