> ## Documentation Index > Fetch the complete documentation index at: https://docs.imini.ai/llms.txt > Use this file to discover all available pages before exploring further. # Nano Banana 2 > Google Gemini 3.1 Flash Image — the most fully featured Flash model, with 14 aspect ratios and 512p to 4K resolutions. ## OpenAPI ````yaml /en/openapi/images/nano-banana-2.yaml POST /v1/images/generate openapi: 3.1.0 info: title: Nano Banana 2 version: '1.0' description: >- Google Gemini 3.1 Flash Image — the most fully featured Flash model, with 14 aspect ratios and 512p to 4K resolutions. servers: - url: https://openapi.imini.ai/imini/router security: - ApiKeyAuth: [] paths: /v1/images/generate: post: summary: Nano Banana 2 description: > Submit an asynchronous image generation task. You will need to poll the query endpoint to retrieve the result. > Model ID: `google/nano-banana-2` · Underlying: Gemini 3.1 Flash Image operationId: generateNanoBanana2 requestBody: required: true content: application/json: schema: type: object required: - model - prompt properties: model: type: string description: Fixed value `google/nano-banana-2`. prompt: type: string description: >- The prompt. Up to **6000** characters. Supports English and Chinese; detail-rich descriptions yield better results. example: >- A cute shiba inu in a spacesuit standing on the moon, 3D cartoon style images: type: array description: >- Reference image list. **Omitting or passing an empty array** means text-to-image mode; passing images switches to image-to-image / style reference mode. Up to **14** images. items: type: object properties: url: type: string description: >- Reference image address, in one of two forms: **1)** A publicly accessible URL (starting with `http://` or `https://`); **2)** A Data URI base64 encoding (starting with `data:image/`, e.g., `data:image/png;base64,iVBORw0KGgo...`). Supported formats: `png` / `jpg` / `webp`, decoded size up to **10MB**. reference_type: type: string description: |- Reference type: - `asset` — content reference - `style` — style reference default: asset enum: - asset - style maxItems: 14 aspect_ratio: type: string description: >- Output aspect ratio. Supports **14 values**: `1:1` `2:3` `3:2` `3:4` `4:3` `4:5` `5:4` `9:16` `16:9` `21:9` `1:4` `1:8` `4:1` `8:1` > When reference images are provided and this parameter is omitted, the model automatically infers the aspect ratio from the reference images and uses it as the output ratio. default: '1:1' enum: - '1:1' - '2:3' - '3:2' - '3:4' - '4:3' - '4:5' - '5:4' - '9:16' - '16:9' - '21:9' - '1:4' - '1:8' - '4:1' - '8:1' resolution: type: string description: >- Output quality tier: `512` / `1K` / `2K` / `4K`. > `512` is an exclusive low-resolution tier for this model family, ideal for quick previews or prototype validation — the lowest cost and fastest option. default: 1K enum: - '512' - 1K - 2K - 4K examples: Text to Image: summary: Text to Image value: model: google/nano-banana-2 prompt: >- A cute shiba inu in a spacesuit standing on the moon, 3D cartoon style aspect_ratio: '1:1' resolution: '512' Image Edit: summary: Image Edit value: model: google/nano-banana-2 prompt: >- A cute shiba inu in a spacesuit standing on the moon, 3D cartoon style images: - url: https://example.com/input.jpg reference_type: asset aspect_ratio: '16:9' resolution: 4K Image Edit (base64): summary: Image Edit (base64) value: model: google/nano-banana-2 prompt: >- A cute shiba inu in a spacesuit standing on the moon, 3D cartoon style images: - url: data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAA... reference_type: asset aspect_ratio: '16:9' resolution: 4K responses: '200': description: Submitted successfully content: application/json: schema: oneOf: - title: Submit Success (Pending) type: object properties: task_id: type: string description: Unique task ID, used for subsequent polling example: task_2041350318103396352 model: type: string description: The model ID used for this task example: google/nano-banana created_at: type: string description: Task creation time example: '2026-04-07T03:00:17.062Z' request_id: type: string description: Unique request ID example: 285f20ce-8158-401b-945c-7bc6a7ef6ead '400': description: Validation Error (e.g. invalid parameter, invalid prompt) content: application/json: schema: type: object properties: error: type: object properties: code: type: string description: Error code, e.g., INVALID_PROMPT example: INVALID_PROMPT message: type: string description: Error message details example: Prompt contains disallowed content status: type: integer description: HTTP status code example: 400 request_id: type: string description: Unique request identifier example: req_abc123 security: - ApiKeyAuth: [] components: securitySchemes: ApiKeyAuth: type: http scheme: bearer bearerFormat: API Key description: > Pass `Authorization: Bearer ` in the request header. Go to the [API Keys management page](https://imini.ai/api-keys) to create and manage API Keys. ````