API Reference

Gemini Image Generation

Generate images through Gemini generateContent; responses may contain both text and image parts.

POST https://api.tu-zi.com/v1beta/models/{model}:generateContent

Preview guide

Paste into an AI assistant to help with integration. Documentation and examples only; no real credentials.

# Gemini Image Generation

Generate images through Gemini generateContent; responses may contain both text and image parts.

## Endpoint and authentication

`POST https://api.tu-zi.com/v1beta/models/{model}:generateContent`

Transport: json

Use an inference API key. Examples contain placeholders; read credentials from environment variables.

```http
Authorization: Bearer YOUR_API_KEY
Content-Type: application/json
```

## Path parameters

| Field | Type | Required | Description / constraints |
| --- | --- | --- | --- |
| model | string | Yes | Selected model identifier. Example: YOUR_MODEL |

## Body parameters

| Field | Type | Required | Description / constraints |
| --- | --- | --- | --- |
| prompt | string | Yes | Image generation or editing prompt. |
| response_modalities | array[string] | Yes | Request image content in the response. |
| aspect_ratio | string | No | Generated image aspect ratio. Values: "1:1", "16:9", "9:16", "4:3", "3:4" |
| image_size | string | No | Output resolution supported by Gemini 3 image models. Values: "1K", "2K", "4K" |

## Minimal request example

```json
{
  "contents": [
    {
      "parts": [
        {
          "text": "Draw a cat"
        }
      ]
    }
  ],
  "generationConfig": {
    "responseModalities": [
      "TEXT",
      "IMAGE"
    ]
  }
}
```

## Before running

Replace https://api.tu-zi.com with this site origin (do not append /v1 twice), and YOUR_MODEL with the exact marketplace model ID. Install requests for Python; use Node.js 20+ and save JavaScript as .mjs. WebSocket samples list their own dependencies.

Create an inference key on the site and set API_KEY in the environment; replace YOUR_API_KEY in cURL. Prepare local input.png/input.wav files for upload examples.

Start with a minimal request, then read the result using the response fields below. For async APIs, a returned task ID requires polling; acceptance does not mean generation has finished.

## Code examples

### curl

```bash
curl --request POST 'https://api.tu-zi.com/v1beta/models/YOUR_MODEL:generateContent' \
  --header 'Authorization: Bearer YOUR_API_KEY' \
  --header 'Content-Type: application/json' \
  --data '{
  "contents": [
    {
      "parts": [
        {
          "text": "Draw a cat"
        }
      ]
    }
  ],
  "generationConfig": {
    "responseModalities": [
      "TEXT",
      "IMAGE"
    ]
  }
}'
```

### python

```python
import json
import os
import requests

url = "https://api.tu-zi.com/v1beta/models/YOUR_MODEL:generateContent"
headers = json.loads("{\"Authorization\":\"Bearer YOUR_API_KEY\",\"Content-Type\":\"application/json\"}")
headers["Authorization"] = "Bearer " + os.environ["API_KEY"]
payload = json.loads("{\"contents\":[{\"parts\":[{\"text\":\"Draw a cat\"}]}],\"generationConfig\":{\"responseModalities\":[\"TEXT\",\"IMAGE\"]}}")
response = requests.request("POST", url, headers=headers, json=payload, timeout=120)
response.raise_for_status()
result = response.json()
if isinstance(result, dict) and (result.get("success") is False or result.get("error")):
    raise RuntimeError(json.dumps(result, ensure_ascii=False))
print(result)  # Also inspect protocol-specific status/code fields.
```

### javascript

```javascript
// Node.js 20+
const url = "https://api.tu-zi.com/v1beta/models/YOUR_MODEL:generateContent";
const headers = {
  "Authorization": "Bearer YOUR_API_KEY",
  "Content-Type": "application/json"
};
headers.Authorization = 'Bearer ' + process.env.API_KEY;
const response = await fetch(url, { method: "POST", headers, body: JSON.stringify({
  "contents": [
    {
      "parts": [
        {
          "text": "Draw a cat"
        }
      ]
    }
  ],
  "generationConfig": {
    "responseModalities": [
      "TEXT",
      "IMAGE"
    ]
  }
}) });
if (!response.ok) throw new Error(await response.text());
const result = await response.json();
if (result?.success === false || result?.error) throw new Error(JSON.stringify(result));
console.log(result); // Also inspect protocol-specific status/code fields.
```

## Response fields

| Field | Type | Description / constraints |
| --- | --- | --- |
| candidates[].content.parts[].text | string | Optional text part; text alone does not prove an image was generated. |
| candidates[].content.parts[].inlineData.mimeType | string | Inline image MIME, such as image/png, image/jpeg or image/webp. |
| candidates[].content.parts[].inlineData.data | string | Base64-encoded image bytes to decode and save, not a URL. |
| candidates[].content.parts[].fileData.fileUri | string | Optional file reference. Only accessible HTTP(S) URLs can be downloaded directly; gs:// and similar references require the corresponding storage access. |
| candidates[].finishReason / promptFeedback.blockReason | string | Completion or blocking reason; inspect when no valid image is present instead of blindly resubmitting. |
| usageMetadata | object | Model usage, not proof that an image was generated. |

Illustrative response; some endpoints show essential fields only. Optional fields may be absent.

```json
{
  "candidates": [
    {
      "content": {
        "role": "model",
        "parts": [
          {
            "text": "Here is the image."
          },
          {
            "inlineData": {
              "mimeType": "image/png",
              "data": "BASE64_IMAGE_BYTES"
            }
          }
        ]
      },
      "finishReason": "STOP"
    }
  ]
}
```

## Errors and retries

Check HTTP status and protocol-specific errors; do not mix error formats across protocols. For 401/403 check credentials and permissions, for 429 back off, and for 5xx check gateway/upstream status. Error bodies may contain error/message/code depending on the protocol.

Use bounded exponential backoff for reads. Do not blindly retry task creation, generation, or key mutations, to avoid duplicate billing or execution.

## Constraints

This page describes the base protocol. Use the selected model quick start for supported fields, enums, limits and asynchronous behavior. Replace YOUR_MODEL. Form initial values are not upstream defaults. The model ID belongs in the URL path. Use contents[].parts[] and generationConfig.responseModalities, not OpenAI messages or data[].url response assumptions. Iterate all candidates[].content.parts[], read inlineData.mimeType and inlineData.data, and validate image/*, Base64 and decoded image bytes before saving. Compatible upstreams may return inline_data/mime_type. HTTP(S) fileData.fileUri can be downloaded; non-HTTP(S) references need separate access. Do not send the site API key to download URLs. Text-only output, empty candidates or no valid image must not be reported as image success; inspect finishReason, promptFeedback and errors. BASE64_IMAGE_BYTES is only an illustrative placeholder.

## Documentation source

Definition version: 1

Reviewed: 2026-11-02

Source: https://api.tu-zi.com/en/docs/api/reference-relay-gemini-image

Related protocol guide: https://api.tu-zi.com/docs/api/gemini

This export contains documentation and examples only, without real credentials, account data or user requests.

Updated 2026-11-02 · Reviewed 2026-11-02

Endpoint and authentication

POST https://api.tu-zi.com/v1beta/models/{model}:generateContent

Transport: json

Use an inference API key. Examples contain placeholders; read credentials from environment variables.

Authorization: Bearer YOUR_API_KEY
Content-Type: application/json

Minimal request example

{
  "contents": [
    {
      "parts": [
        {
          "text": "Draw a cat"
        }
      ]
    }
  ],
  "generationConfig": {
    "responseModalities": [
      "TEXT",
      "IMAGE"
    ]
  }
}

Before running

Replace https://api.tu-zi.com with this site origin (do not append /v1 twice), and YOUR_MODEL with the exact marketplace model ID. Install requests for Python; use Node.js 20+ and save JavaScript as .mjs. WebSocket samples list their own dependencies.

Create an inference key on the site and set API_KEY in the environment; replace YOUR_API_KEY in cURL. Prepare local input.png/input.wav files for upload examples.

Start with a minimal request, then read the result using the response fields below. For async APIs, a returned task ID requires polling; acceptance does not mean generation has finished.

Constraints

This page describes the base protocol. Use the selected model quick start for supported fields, enums, limits and asynchronous behavior. Replace YOUR_MODEL. Form initial values are not upstream defaults. The model ID belongs in the URL path. Use contents[].parts[] and generationConfig.responseModalities, not OpenAI messages or data[].url response assumptions. Iterate all candidates[].content.parts[], read inlineData.mimeType and inlineData.data, and validate image/*, Base64 and decoded image bytes before saving. Compatible upstreams may return inline_data/mime_type. HTTP(S) fileData.fileUri can be downloaded; non-HTTP(S) references need separate access. Do not send the site API key to download URLs. Text-only output, empty candidates or no valid image must not be reported as image success; inspect finishReason, promptFeedback and errors. BASE64_IMAGE_BYTES is only an illustrative placeholder.

Path parameters

Field	Type	Required	Description / constraints
model	string	Yes	Selected model identifier. Example: YOUR_MODEL

Body parameters

Field	Type	Required	Description / constraints
prompt	string	Yes	Image generation or editing prompt.
response_modalities	array[string]	Yes	Request image content in the response.
aspect_ratio	string	No	Generated image aspect ratio. Values: "1:1", "16:9", "9:16", "4:3", "3:4"
image_size	string	No	Output resolution supported by Gemini 3 image models. Values: "1K", "2K", "4K"

Response fields

Field	Type	Description / constraints
candidates[].content.parts[].text	string	Optional text part; text alone does not prove an image was generated.
candidates[].content.parts[].inlineData.mimeType	string	Inline image MIME, such as image/png, image/jpeg or image/webp.
candidates[].content.parts[].inlineData.data	string	Base64-encoded image bytes to decode and save, not a URL.
candidates[].content.parts[].fileData.fileUri	string	Optional file reference. Only accessible HTTP(S) URLs can be downloaded directly; gs:// and similar references require the corresponding storage access.
candidates[].finishReason / promptFeedback.blockReason	string	Completion or blocking reason; inspect when no valid image is present instead of blindly resubmitting.
usageMetadata	object	Model usage, not proof that an image was generated.

Illustrative response; some endpoints show essential fields only. Optional fields may be absent.

{
  "candidates": [
    {
      "content": {
        "role": "model",
        "parts": [
          {
            "text": "Here is the image."
          },
          {
            "inlineData": {
              "mimeType": "image/png",
              "data": "BASE64_IMAGE_BYTES"
            }
          }
        ]
      },
      "finishReason": "STOP"
    }
  ]
}

Errors and retries

Check HTTP status and protocol-specific errors; do not mix error formats across protocols. For 401/403 check credentials and permissions, for 429 back off, and for 5xx check gateway/upstream status. Error bodies may contain error/message/code depending on the protocol.

Use bounded exponential backoff for reads. Do not blindly retry task creation, generation, or key mutations, to avoid duplicate billing or execution.

Document information and sources

Documentation source

Definition version: 1

Reviewed: 2026-11-02

Source: https://api.tu-zi.com/en/docs/api/reference-relay-gemini-image

Related protocol guide: https://api.tu-zi.com/docs/api/gemini

This export contains documentation and examples only, without real credentials, account data or user requests.

Request examples

curl --request POST 'https://api.tu-zi.com/v1beta/models/YOUR_MODEL:generateContent' \
  --header 'Authorization: Bearer YOUR_API_KEY' \
  --header 'Content-Type: application/json' \
  --data '{
  "contents": [
    {
      "parts": [
        {
          "text": "Draw a cat"
        }
      ]
    }
  ],
  "generationConfig": {
    "responseModalities": [
      "TEXT",
      "IMAGE"
    ]
  }
}'

import json
import os
import requests

url = "https://api.tu-zi.com/v1beta/models/YOUR_MODEL:generateContent"
headers = json.loads("{\"Authorization\":\"Bearer YOUR_API_KEY\",\"Content-Type\":\"application/json\"}")
headers["Authorization"] = "Bearer " + os.environ["API_KEY"]
payload = json.loads("{\"contents\":[{\"parts\":[{\"text\":\"Draw a cat\"}]}],\"generationConfig\":{\"responseModalities\":[\"TEXT\",\"IMAGE\"]}}")
response = requests.request("POST", url, headers=headers, json=payload, timeout=120)
response.raise_for_status()
result = response.json()
if isinstance(result, dict) and (result.get("success") is False or result.get("error")):
    raise RuntimeError(json.dumps(result, ensure_ascii=False))
print(result)  # Also inspect protocol-specific status/code fields.

// Node.js 20+
const url = "https://api.tu-zi.com/v1beta/models/YOUR_MODEL:generateContent";
const headers = {
  "Authorization": "Bearer YOUR_API_KEY",
  "Content-Type": "application/json"
};
headers.Authorization = 'Bearer ' + process.env.API_KEY;
const response = await fetch(url, { method: "POST", headers, body: JSON.stringify({
  "contents": [
    {
      "parts": [
        {
          "text": "Draw a cat"
        }
      ]
    }
  ],
  "generationConfig": {
    "responseModalities": [
      "TEXT",
      "IMAGE"
    ]
  }
}) });
if (!response.ok) throw new Error(await response.text());
const result = await response.json();
if (result?.success === false || result?.error) throw new Error(JSON.stringify(result));
console.log(result); // Also inspect protocol-specific status/code fields.