This is a known issue with Auto mode. Auto mode routes through additional server-side steps that can introduce latency or failures, and you’ve correctly identified the workaround: selecting a specific model directly (like Sonnet 4.6) bypasses this and works reliably.
The team is actively working on improving Auto mode routing. For now, sticking with a manually selected model is the best path.
If you’re willing to share a Request ID from one of the failing Auto mode attempts (top right of the chat > three dots > Copy Request ID), that would help the team investigate your specific case further. Completely understand if you’d prefer not to given the sensitivity.
This happens to me since days ago with even with claude-4.6-opus-high selected manually. It is very annoying because it often happens in the middle of thinking.
In case it helps, it seems that it only happens after leaving the application unattended for a while, i. e. computer unattended or Cursor application working in the background.
The chat hanging / ‘Taking longer than expected’ issue has been addressed in a recent Cursor update. Updating to the latest version should resolve this.
The fix was primarily server-side, so you shouldn’t need a client update. If you want to make sure you’re on the absolute latest, you can check via Cursor Settings > About > Check for Updates (or Command Palette > Attempt Update).
Are you still seeing the hang on 3.0.12? Your earlier report (post #9) describes a slightly different pattern from the original thread: hangs with manually selected models (not Auto mode), specifically after leaving Cursor unattended. If that’s still happening, could you share a Request ID from one of those failing attempts? That would help us determine whether the idle-related hang is a separate issue.
