Troubleshooting & FAQ
What to do when a build fails, an app won't open, or a message looks unfamiliar — plus answers to common questions.
Most app issues are recoverable — your last working version and full history are always safe. Here's how to read the common ones.
Build & save errors
- The chosen model is unavailable — it's temporarily down or rate-limited. Try again, or switch to another model and continue.
- Compile / bundle / save failed — a code change didn't build. The editor flags the error with its line number and offers Retry. You can also Revert file to discard the change, or ask the agent to fix it.
- A runtime error in the running app — a Fix runtime error banner appears in the composer. Click it to load a repair prompt and send it to the agent.
- A fork or fuse didn't complete — the action reports the failure in its dialog. Your source app is unaffected; run the action again.
"Private preview"
A Private preview page that asks you to open the app from its workspace means the app is an unpublished draft — only the project's editors can open it. Publish it to make it openable by anyone with the link.