OpenRouter's image-editing tutorial shows how an application can send a source image and a written change request to Nano Banana 2, the nickname for Google's Gemini 3.1 Flash image model. The response contains an encoded image that the application decodes into a usable file.
Successive edits work by submitting the latest result as the next input. Earlier prompts are not remembered automatically, so each request should restate what must remain unchanged. This makes the image itself the connection between editing steps and gives the application an intermediate result to inspect or retain before continuing.
