[Bug] UI shows Gemini 3.1 Pro selected, but backend continues to use Opus (Silent quota drain)

Google Antigravity
1

Environment:

  • Device: MacBook M4

  • OS: macOS

  • App/Platform: Antigravity (Note: Recent update installed)

Description: Hi team, I am experiencing a critical bug with the model selector after the most recent update. The UI does not sync with the backend, causing the app to silently drain my quota for a model I am no longer actively using.

Steps to Reproduce:

  1. Start a prompt session and select Opus for an important task.

  2. After finishing that specific task, switch the model selector to Gemini 3.1 Pro to continue working.

  3. Send multiple new prompts.

Expected Behavior: Once switched, the prompts should be routed to Gemini 3.1 Pro, and my Opus quota should remain untouched.

Actual Behavior: Even though the dropdown/UI clearly shows that Gemini 3.1 Pro is the active model, the app continues to send all prompts to Opus in the background. This happened to me twice, and I only realized the issue when I suddenly received a “Quota Exhausted” error for Opus. Checking the prompt history/model usage confirmed that Opus was being used for every prompt despite Gemini 3.1 Pro being selected on the screen.

Impact: This is a highly frustrating issue as it wastes premium model quotas without the user’s knowledge. Could you please look into this UI/backend mismatch urgently?

Thanks.