Antigravity IDE 2.6.0 no longer ships its 135 MB language server. A new JavaScript extension starts the Antigravity CLI (agy --hub) as its backend, the same extension Google describes as bringing Antigravity to Visual Studio Code.
Google removed Gemini 3.1 Pro from Antigravity on October 13, then launched Gemini 4 Argon the same day, but only for Ultra. On Google AI Pro and free plans, the best Gemini left is 3.8 Flash.
Antigravity 2.23.0 ships gemini-4-argon with Low, Medium and High variants and ready-made model picker labels. Meanwhile Gemini 3.1 Pro, 3.6 and 3.7 Flash were just removed from Antigravity.
A gemini-3.1-ultra model string appeared in Google's Antigravity CLI 1.3.1, days after Gemini 4 Argon. We verified it in the binary, checked agy models and tried to run it. Here's what we found.