Gemini-3.1-Flash Official Image Generation

curl --request POST \
  --url https://toapis.com/v1/images/generations \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '{
    "model": "gemini-3.1-flash-image-official",
    "prompt": "An ink wash painting of mountains and rivers, layered peaks with swirling mist",
    "size": "16:9",
    "n": 1,
    "metadata": {
      "temperature": 1.0,
      "topP": 0.95,
      "resolution": "1K",
      "personGeneration": "ALLOW_ALL",
      "thinkingConfig": {
        "thinkingLevel": "HIGH"
      }
    }
  }'

import requests

response = requests.post(
    "https://toapis.com/v1/images/generations",
    headers={
        "Authorization": "Bearer your-ToAPIs-key",
        "Content-Type": "application/json"
    },
    json={
        "model": "gemini-3.1-flash-image-official",
        "prompt": "An ink wash painting of mountains and rivers, layered peaks with swirling mist",
        "size": "16:9",
        "n": 1,
        "metadata": {
            "temperature": 1.0,
            "topP": 0.95,
            "resolution": "1K",
            "personGeneration": "ALLOW_ALL",
            "thinkingConfig": {
                "thinkingLevel": "HIGH"
            }
        }
    }
)

task = response.json()
print(f"Task ID: {task['id']}")
print(f"Status: {task['status']}")

const response = await fetch('https://toapis.com/v1/images/generations', {
  method: 'POST',
  headers: {
    'Authorization': 'Bearer your-ToAPIs-key',
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({
    model: 'gemini-3.1-flash-image-official',
    prompt: 'An ink wash painting of mountains and rivers, layered peaks with swirling mist',
    size: '16:9',
    n: 1,
    metadata: {
      temperature: 1.0,
      topP: 0.95,
      resolution: '1K',
      personGeneration: 'ALLOW_ALL',
      thinkingConfig: {
        thinkingLevel: 'HIGH'
      }
    }
  })
});

const task = await response.json();
console.log(`Task ID: ${task.id}`);
console.log(`Status: ${task.status}`);

{
  "id": "task_img_abc123def456",
  "object": "generation.task",
  "model": "gemini-3.1-flash-image-official",
  "status": "queued",
  "progress": 0,
  "created_at": 1703884800,
  "metadata": {}
}

POST

images

generations

curl --request POST \
  --url https://toapis.com/v1/images/generations \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '{
    "model": "gemini-3.1-flash-image-official",
    "prompt": "An ink wash painting of mountains and rivers, layered peaks with swirling mist",
    "size": "16:9",
    "n": 1,
    "metadata": {
      "temperature": 1.0,
      "topP": 0.95,
      "resolution": "1K",
      "personGeneration": "ALLOW_ALL",
      "thinkingConfig": {
        "thinkingLevel": "HIGH"
      }
    }
  }'

import requests

response = requests.post(
    "https://toapis.com/v1/images/generations",
    headers={
        "Authorization": "Bearer your-ToAPIs-key",
        "Content-Type": "application/json"
    },
    json={
        "model": "gemini-3.1-flash-image-official",
        "prompt": "An ink wash painting of mountains and rivers, layered peaks with swirling mist",
        "size": "16:9",
        "n": 1,
        "metadata": {
            "temperature": 1.0,
            "topP": 0.95,
            "resolution": "1K",
            "personGeneration": "ALLOW_ALL",
            "thinkingConfig": {
                "thinkingLevel": "HIGH"
            }
        }
    }
)

task = response.json()
print(f"Task ID: {task['id']}")
print(f"Status: {task['status']}")

const response = await fetch('https://toapis.com/v1/images/generations', {
  method: 'POST',
  headers: {
    'Authorization': 'Bearer your-ToAPIs-key',
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({
    model: 'gemini-3.1-flash-image-official',
    prompt: 'An ink wash painting of mountains and rivers, layered peaks with swirling mist',
    size: '16:9',
    n: 1,
    metadata: {
      temperature: 1.0,
      topP: 0.95,
      resolution: '1K',
      personGeneration: 'ALLOW_ALL',
      thinkingConfig: {
        thinkingLevel: 'HIGH'
      }
    }
  })
});

const task = await response.json();
console.log(`Task ID: ${task.id}`);
console.log(`Status: ${task.status}`);

{
  "id": "task_img_abc123def456",
  "object": "generation.task",
  "model": "gemini-3.1-flash-image-official",
  "status": "queued",
  "progress": 0,
  "created_at": 1703884800,
  "metadata": {}
}

Note for users in mainland China: Please use https://toapis.cn as the API endpoint (Base URL). Replace https://toapis.com with https://toapis.cn in the examples in this document.

Direct connection to Google Vertex AI using the Gemini 3.1 Flash Image native API
Select the gemini-3.1-flash-image-official model via the model parameter
Nano Banana 2 aliases: nano-banana-2-lite-official and nano-banana-2-official
Supports text-to-image and image-to-image generation
Supports native generation parameters like temperature, topP, and maxOutputTokens
Supports resolution (1K/2K/4K), personGeneration, and imageOutputOptions image configuration
Supports thinkingConfig thinking mode for improved complex scene generation
Supports safetySettings for content safety control
Supports extreme aspect ratios (4:1, 8:1)
Asynchronous task management with task ID for result querying

Important Change: For better performance and cost control, we no longer support passing base64 image data directly in image_urls. Please use the Upload Image endpoint to upload images first, then use the returned URL in this API.

Authorizations

string

required

All endpoints require Bearer Token authenticationGet API Key: Visit the API Key Management page to obtain your API KeyAdd to request headers:

Authorization: Bearer YOUR_API_KEY

Body

string

default:"gemini-3.1-flash-image-official"

required

Image generation model nameExample: "gemini-3.1-flash-image-official"

string

required

Text description for image generation

string

Image aspect ratioSupported formats:

1:1 - Square
3:2 / 2:3
3:4 / 4:3
4:5 / 5:4
9:16 / 16:9
21:9
4:1 / 8:1 - Extreme widescreen ratios

integer

default:1

Number of images to generateFixed at 1

string[]

Reference image URL array for image-to-image generation or editing⚠️ Only URL format is supported (base64 is no longer supported)

Publicly accessible image URLs (http:// or https://)
Use the Upload Image endpoint to upload local images and get URLs

Limits:

Maximum 14 images
Maximum file size per image: 10MB
Supported formats: .jpeg, .jpg, .png, .webp

object

Vertex AI native extension parameters

Show Show metadata fields

number

Generation temperature, controls output randomnessRange: 0.0 - 2.0, default 1.0

number

Top-P sampling parameterRange: 0.0 - 1.0, default 0.95

integer

Maximum output tokensDefault 32768

string

Output image resolution, automatically mapped to Vertex AI native imageSizeOptions: 1K, 2K, 4K, default 1K

string

Person generation controlOptions:

ALLOW_ALL - Allow generating all people (including adults and children)
ALLOW_ADULT - Allow generating adults only
ALLOW_NONE - Disallow generating people

object

Image output format configuration

Show imageOutputOptions fields

string

Output image formatOptions: image/png, image/jpeg, image/webp

integer

Compression quality (JPEG only)

object

Thinking mode configuration. When enabled, the model reasons before generating images, improving results for complex scenes

Show thinkingConfig fields

integer

Thinking token budget, controls the depth of model reasoningRange: 0 - 24576, default is determined by the model

string

Thinking levelOptions: LOW, MEDIUM, HIGH, MINIMAL

array

Safety settings array for content safety filtering

Show safetySettings elements

string

Safety categoryOptions: HARM_CATEGORY_HATE_SPEECH, HARM_CATEGORY_DANGEROUS_CONTENT, HARM_CATEGORY_SEXUALLY_EXPLICIT, HARM_CATEGORY_HARASSMENT

string

Filtering thresholdOptions: OFF, BLOCK_LOW_AND_ABOVE, BLOCK_MEDIUM_AND_ABOVE, BLOCK_ONLY_HIGH

Response

string

Unique task identifier for querying task status

string

Object type, always generation.task

string

Model name used

string

Task status

queued - Queued for processing
in_progress - Processing
completed - Successfully completed
failed - Failed

integer

Task progress percentage (0-100)

integer

Task creation timestamp (Unix timestamp)

object

Task metadata

curl --request POST \
  --url https://toapis.com/v1/images/generations \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '{
    "model": "gemini-3.1-flash-image-official",
    "prompt": "An ink wash painting of mountains and rivers, layered peaks with swirling mist",
    "size": "16:9",
    "n": 1,
    "metadata": {
      "temperature": 1.0,
      "topP": 0.95,
      "resolution": "1K",
      "personGeneration": "ALLOW_ALL",
      "thinkingConfig": {
        "thinkingLevel": "HIGH"
      }
    }
  }'

import requests

response = requests.post(
    "https://toapis.com/v1/images/generations",
    headers={
        "Authorization": "Bearer your-ToAPIs-key",
        "Content-Type": "application/json"
    },
    json={
        "model": "gemini-3.1-flash-image-official",
        "prompt": "An ink wash painting of mountains and rivers, layered peaks with swirling mist",
        "size": "16:9",
        "n": 1,
        "metadata": {
            "temperature": 1.0,
            "topP": 0.95,
            "resolution": "1K",
            "personGeneration": "ALLOW_ALL",
            "thinkingConfig": {
                "thinkingLevel": "HIGH"
            }
        }
    }
)

task = response.json()
print(f"Task ID: {task['id']}")
print(f"Status: {task['status']}")

const response = await fetch('https://toapis.com/v1/images/generations', {
  method: 'POST',
  headers: {
    'Authorization': 'Bearer your-ToAPIs-key',
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({
    model: 'gemini-3.1-flash-image-official',
    prompt: 'An ink wash painting of mountains and rivers, layered peaks with swirling mist',
    size: '16:9',
    n: 1,
    metadata: {
      temperature: 1.0,
      topP: 0.95,
      resolution: '1K',
      personGeneration: 'ALLOW_ALL',
      thinkingConfig: {
        thinkingLevel: 'HIGH'
      }
    }
  })
});

const task = await response.json();
console.log(`Task ID: ${task.id}`);
console.log(`Status: ${task.status}`);

{
  "id": "task_img_abc123def456",
  "object": "generation.task",
  "model": "gemini-3.1-flash-image-official",
  "status": "queued",
  "progress": 0,
  "created_at": 1703884800,
  "metadata": {}
}

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Gemini-3.1-Flash Official Image Generation

Authorizations

Body

Response

​Authorizations

​Body

​Response

Authorizations

Body

Response