Google - Nano Banana 2.1

This page is generated from the upstream official OpenAPI documentation. Endpoints, parameters and examples match the official docs; brand and API domain are replaced with ModelFold.

Endpoint

POST /jobs/createTask

Full URL: https://ai.modelfold.online/v1/jobs/createTask

Authentication: every request must include the Authorization: Bearer <API_KEY> header.

Image generation by Nano Banana 2.1

Query Task Status

After submitting a task, use the unified query endpoint to check progress and retrieve results:

• Get Task Details — Learn how to query task status and retrieve generation results

TIP

For production use, we recommend using the callBackUrl parameter to receive automatic notifications when generation completes, rather than polling the status endpoint.

Related Resources

• Market Overview — Explore all available models
• Common API — Check credits and account usage

Request Parameters

Body (application/json)

Parameter	Type	Required	Description
model	string	Yes	The model name to use for generation. Required field. - Must be nano-banana-2-1 for this endpoint Default："nano-banana-2-1"。 Allowed values：nano-banana-2-1。 示例：nano-banana-2-1。
callBackUrl	string	No	The URL to receive generation task completion updates. Optional but recommended for production use. - System will POST task status and results to this URL when generation completes - Callback includes generated content URLs and task information - Your callback endpoint should accept POST requests with JSON payload containing results - Alternatively, use the Get Task Details endpoint to poll task status - To ensure callback security, see Webhook Verification Guide for signature verification implementation 示例：https://your-domain.com/api/callback。
input	object	Yes	Input parameters for the generation task
input.prompt	string	Yes	A text description of the image you want to generate (Max length: 20000 characters) 示例：Comic poster: cool banana hero in shades leaps from sci-fi pad. Six panels: 1) 4K mountain landscape, 2) banana holds page of long multilingual text with auto translation, 3) Gemini 3 hologram for search/knowledge/reasoning, 4) camera UI sliders for angle focus color, 5) frame trio 1:1-9:16, 6) consistent banana poses. Footer shows Google icons. Tagline: Nano Banana Pro now on ModelFold AI.。
input.image_input	array<string>	No	Input images to transform or use as reference (supports up to 10 images) (File URL after upload, not file content; Accepted types: image/jpeg, image/png, image/webp; Max size: 30.0MB)
input.aspect_ratio	string	No	Aspect ratio of the generated image Default："auto"。 Allowed values：1:1 / 2:3 / 3:2 / 1:4 / 4:1 / 3:4 / 4:3 / 4:5 / 5:4 / 1:8 / 8:1 / 9:16 / 16:9 / 21:9 / auto。 示例：1:1。
input.resolution	string	No	Resolution of the generated image Default："1K"。 Allowed values：1K / 2K / 4K。 示例：1K。
input.output_format	string	No	Format of the output image Default："jpg"。 Allowed values：png / jpg。 示例：jpg。

Request Example

curl -X POST "https://ai.modelfold.online/v1/jobs/createTask" \
  -H "Authorization: Bearer $MODELFOLD_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
  "model": "nano-banana-2-1",
  "callBackUrl": "https://your-domain.com/api/callback",
  "input": {
    "prompt": "Comic poster: cool banana hero in shades leaps from sci-fi pad. Six panels: 1) 4K mountain landscape, 2) banana holds page of long multilingual text with auto translation, 3) Gemini 3 hologram for search/knowledge/reasoning, 4) camera UI sliders for angle focus color, 5) frame trio 1:1-9:16, 6) consistent banana poses. Footer shows Google icons. Tagline: Nano Banana Pro now on ModelFold AI.",
    "image_input": [],
    "aspect_ratio": "auto",
    "resolution": "1K",
    "output_format": "png"
  }
}'

{
  "model": "nano-banana-2-1",
  "callBackUrl": "https://your-domain.com/api/callback",
  "input": {
    "prompt": "Comic poster: cool banana hero in shades leaps from sci-fi pad. Six panels: 1) 4K mountain landscape, 2) banana holds page of long multilingual text with auto translation, 3) Gemini 3 hologram for search/knowledge/reasoning, 4) camera UI sliders for angle focus color, 5) frame trio 1:1-9:16, 6) consistent banana poses. Footer shows Google icons. Tagline: Nano Banana Pro now on ModelFold AI.",
    "image_input": [],
    "aspect_ratio": "auto",
    "resolution": "1K",
    "output_format": "png"
  }
}

Response

200 — Request successful.

参数	类型	必填	说明
code	integer	否	Status code of the request. The HTTP status is 200 even when the request fails, so always check this field: 200 means success; any other value means the request failed and msg describes the reason. Common values: 401 invalid or missing API key; 402 insufficient credits; 429 rate limit exceeded; 422 or 500 the request could not be processed (read msg and check your parameters before retrying). 可选值：200 / 401 / 402 / 404 / 422 / 429 / 433 / 455 / 500 / 501 / 505。 示例：200。
msg	string	否	Response message, error description upon failure 示例：success。
data	object	是	—
data.taskId	string	是	The task ID can be used with the "Get Task Details" endpoint to query the task status. 示例：dc1928bfcbc77cb6c85f3359a9c718b3。

{
  "code": 200,
  "msg": "success",
  "data": {
    "taskId": "dc1928bfcbc77cb6c85f3359a9c718b3"
  }
}

500 — Server error.

参数	类型	必填	说明
code	integer	是	Response status code - 200: Success - Request has been processed successfully - 401: Unauthorized - Authentication credentials are missing or invalid - 402: Insufficient Credits - Account does not have enough credits to perform the operation - 404: Not Found - The requested resource or endpoint does not exist - 408: Timeout - No result has been returned for over 10 minutes. - 422: Validation Error - The request parameters failed validation checks - 429: Rate Limited - Request limit has been exceeded for this resource - 455: Service Unavailable - System is currently undergoing maintenance - 500: Server Error - An unexpected error occurred while processing the request - 501: Generation Failed - Content generation task failed - 505: Feature Disabled - The requested feature is currently disabled
msg	string	是	Response message, error description when failed
data	object	是	—

{
  "code": 500,
  "msg": "Server Error - An unexpected error occurred while processing the request",
  "data": null
}

Callback

onImageGenerated

Callback URL: {$request.body#/callBackUrl} (the callBackUrl in the request body).

Sent when the task succeeds or fails.

Callback body parameters

参数	类型	必填	说明
code	integer	否	200: success. 501: failure; see data.failCode and data.failMsg. Allowed values：200 / 501。 示例：200。
msg	string	否	Status message 示例：Playground task completed successfully.。
data	object	否	—
data.completeTime	integer	否	Task completion time, represented as a Unix timestamp in milliseconds 示例：1786427040000。
data.costTime	integer	否	Processing time in seconds. Present on both success and failure callbacks. 示例：48。
data.createTime	integer	否	Task creation time, represented as a Unix timestamp in milliseconds 示例：1786426989000。
data.creditsConsumed	number	否	Credits consumed by the task; 0 for failed tasks. 示例：5。
data.model	string	否	Image generation model used for the task 示例：nano-banana-2-1。
data.param	string	否	Parameters submitted when creating the task, in JSON string format 示例：{"input":"{\"image_input\":[],\"aspect_ratio\":\"auto\",\"output_format\":\"jpg\",\"prompt\":\"A highly detailed illustration of a futuristic banana-shaped spaceship flying above a neon city at night, with realistic lighting, cinematic effects, and 4K quality.\",\"resolution\":\"2K\"}","callBackUrl":"https://your-domain.com/api/callback","model":"nano-banana-2-1"}。
data.resultJson	string	否	Image generation result in JSON string format. resultUrls contains the list of generated image URLs. Present only when state is success. 示例：{"resultUrls":["https://tempfile.aiquickdraw.com/workers/images/image_90b6bf4499a80b74a2b5ee640b7aaf70.jpg"]}。
data.state	string	否	Task status Allowed values：success / fail。 示例：success。
data.taskId	string	否	Task ID 示例：a2a1622f9daca036d85f4b63e74eb4af。
data.updateTime	integer	否	Use completeTime as the completion time; updateTime may equal createTime. 示例：1786427040000。
data.failCode	string	否	Failure code, a numeric string such as "400" or "500". Present only when state is fail. 示例：500。
data.failMsg	string	否	Failure reason. Present only when state is fail. 示例：<error detail>。

Success

{
  "code": 200,
  "msg": "Playground task completed successfully.",
  "data": {
    "taskId": "a2a1622f9daca036d85f4b63e74eb4af",
    "model": "nano-banana-2-1",
    "state": "success",
    "param": "{\"input\":\"{\\\"image_input\\\":[],\\\"aspect_ratio\\\":\\\"auto\\\",\\\"output_format\\\":\\\"jpg\\\",\\\"prompt\\\":\\\"A highly detailed illustration of a futuristic banana-shaped spaceship flying above a neon city at night, with realistic lighting, cinematic effects, and 4K quality.\\\",\\\"resolution\\\":\\\"2K\\\"}\",\"callBackUrl\":\"https://your-domain.com/api/callback\",\"model\":\"nano-banana-2-1\"}",
    "resultJson": "{\"resultUrls\":[\"https://tempfile.aiquickdraw.com/workers/images/image_90b6bf4499a80b74a2b5ee640b7aaf70.jpg\"]}",
    "completeTime": 1786427040000,
    "createTime": 1786426989000,
    "costTime": 48,
    "creditsConsumed": 5,
    "updateTime": 1786427040000
  }
}

Failure

{
  "code": 501,
  "msg": "Playground task failed.",
  "data": {
    "taskId": "a2a1622f9daca036d85f4b63e74eb4af",
    "model": "nano-banana-2-1",
    "state": "fail",
    "param": "{\"input\":\"{\\\"image_input\\\":[],\\\"aspect_ratio\\\":\\\"auto\\\",\\\"output_format\\\":\\\"jpg\\\",\\\"prompt\\\":\\\"A highly detailed illustration of a futuristic banana-shaped spaceship flying above a neon city at night, with realistic lighting, cinematic effects, and 4K quality.\\\",\\\"resolution\\\":\\\"2K\\\"}\",\"callBackUrl\":\"https://your-domain.com/api/callback\",\"model\":\"nano-banana-2-1\"}",
    "failCode": "500",
    "failMsg": "<error detail>",
    "completeTime": 1786427040000,
    "createTime": 1786426989000,
    "costTime": 48,
    "creditsConsumed": 0,
    "updateTime": 1786427040000
  }
}