Hey Don! Yep, Gemini Image Pro is ready to go in the API. Here are the model strings:
gemini-2.5-flash-image → standard Gemini/Nano Banana, fast
gemini-3-pro-image → Gemini Pro (2K resolution)
gemini-3-pro-image-hd → Ultra only (4K resolution)
Usage looks like this:
json
"imageOptions": {
"source": "aiGenerated",
"model": "gemini-3-pro-image"
}Quick note: if you hit a "Model not available on plan" error, it just means that specific model requires a higher workspace tier.
The docs at developers.gamma.app might be a bit behind on listing all the newest models, but they should work if you pass them in directly. Let me know if you run into any issues!