Watch the iPhone, not the agent. After you prompt your agent, the result appears on the iPhone preview. That is the only surface that matters.

Keep it running. Just keep the app open. If you quit, open Prototo again and pick up where you left off.

You do not repeat your design system. Your agent reads DESIGN.md every time. Describe the screen: layout, content, feel. The colours and fonts you already chose during setup come along on their own.

Be specific. “Add a card” gets a guess. “Add a card with a glass background, merchant name at the top, amount large in the centre” gets what you pictured. More examples in How to prompt Prototo.

Change screens in plain language. You do not edit files. Say what to change: “on the settings screen, move sign out to the bottom and make it red.”

Your agent checks its own work. After each screen it writes, it takes a screenshot of the live iPhone, type-checks the project, and reads the current errors itself. If you change the navigation (tabs, root layout), it can restart the app on its own too. You rarely need to relay what you see.

If a screen looks broken, ask the agent to fix it:

fix any errors in the Settings screen

Replace Settings with your screen name. You do not need to read the error.

When nothing else works, reset. Click Reload in the toolbar under the iPhone, or choose View › Restart Preview. That restarts your prototype and the preview. It fixes most stuck states. Details in Troubleshooting.