1. User requests an action in an external app (e.g., "Send email to sarah@acme.com about the launch").
2. Claude identifies the required tool using Composio Tool Router.
3. If it's the first time using the app, the user authorizes the connection via OAuth.
4. The action is executed in the external app.
5. The result is returned to Claude.
6. Claude informs the user about the outcome.