I have google ai pro plan and tried antigravity with 3.5 flash but it used up all my quota in two prompts. If that is not a bug then it is seriously unusable.
API price for gemini-3.5-flash is 3x gemini-3-flash-preview so they might be throttling it 3x sooner. They should either drop API prices or not advertise AI Pro as supporting Antigravity.
https://ai.google.dev/gemini-api/docs/pricing#gemini-3.5-fla...