Preview and environment problems
Resolve missing apps, stale links, sleeping machines, and setup failures.
A preview registration contains the app's access metadata. It does not prove that the server is running or healthy. Start with the symptom and keep the session's environment state in view.
No preview is listed
Ask the agent to start the app on the intended port and register its preview. Confirm that the task actually includes a runnable app; a code-only or document task may not produce a web preview.
The preview is blank or refuses the connection
Ask the agent to inspect the app process, listening port, startup command, and current logs. A machine can be ready while its app process has exited. Verify the app responds inside the environment before repeatedly refreshing its external link.
Access expired or the environment is asleep
Refresh preview access through Uno when the link is stale. Use the wake action for a sleeping environment and wait for the wake result.
Waking a machine does not necessarily restart the app server. If the preview still fails, ask the agent to verify and restart the process. A wake from another part of the app can also leave the preview holding an older access link, so refresh it there.
The layout looks like mobile
Inspect Desktop or Responsive mode, the preview pane width, and the app's viewport. A narrow inspector can show a mobile layout. Zoom and screenshot scaling do not establish the browser's layout width.
State the intended viewport when reporting a layout issue. For feedback on a particular element, use preview annotations.
Setup or snapshot failed
Read the first failed build step. Check the manifest, supporting files, package install command, and secret scope. Use GitHub troubleshooting for checkout or authorization failures.
See snapshots, desktop and mobile views, and session recovery.