Gemini 3.1 Flash Image - MixRoute API

新版图片模型使用 Nano Banana 2.1，ID 为 gemini-nano-banana-2.1；其最低输出档位为 1K，默认思考等级为 MEDIUM。下方仍是 gemini-3.1-flash-image 的示例，实际可用性以账号模型列表为准。

Gemini 3.1 Flash Image 可通过下方原生图片接口调用。使用 Gemini 原生 Content/Part 结构，请求 IMAGE 输出并读取返回的图片片段，不将其当作纯文本聊天接口。

原生图片参数 | 流式响应

POST https://api.mixroute.ai/v1/models/gemini-3.1-flash-image:generateContent

调用示例

将 MixRoute Key 设置到环境变量 MIXROUTE_API_KEY，通过 Authorization: Bearer ... 认证。编辑图片前，将素材占位值替换为可访问的图片或本地文件。

curl --request POST "https://api.mixroute.ai/v1/models/gemini-3.1-flash-image:generateContent" \
  --header "Authorization: Bearer $MIXROUTE_API_KEY" \
  --header "Content-Type: application/json" \
  --data '{
  "contents": [
    {
      "role": "user",
      "parts": [
        {
          "text": "A clean product photograph of a red ceramic mug on a white background."
        }
      ]
    }
  ],
  "generationConfig": {
    "responseModalities": [
      "TEXT",
      "IMAGE"
    ],
    "imageConfig": {
      "aspectRatio": "1:1",
      "imageSize": "1K"
    }
  }
}'

Python

import json
import os
import requests

payload = json.loads(r'''
{
  "contents": [
    {
      "role": "user",
      "parts": [
        {
          "text": "A clean product photograph of a red ceramic mug on a white background."
        }
      ]
    }
  ],
  "generationConfig": {
    "responseModalities": [
      "TEXT",
      "IMAGE"
    ],
    "imageConfig": {
      "aspectRatio": "1:1",
      "imageSize": "1K"
    }
  }
}
''')
response = requests.post(
    "https://api.mixroute.ai/v1/models/gemini-3.1-flash-image:generateContent",
    headers={"Authorization": "Bearer " + os.environ["MIXROUTE_API_KEY"]},
    json=payload,
    timeout=180,
)
response.raise_for_status()
result = response.json()
import base64
from pathlib import Path

image_index = 0
for candidate in result.get("candidates", []):
    for part in candidate.get("content", {}).get("parts", []):
        if part.get("thought"):
            continue
        inline = part.get("inlineData")
        if inline and inline.get("data"):
            extension = {"image/png": "png", "image/jpeg": "jpg", "image/webp": "webp"}.get(inline.get("mimeType"), "bin")
            Path(f"image_{image_index}.{extension}").write_bytes(base64.b64decode(inline["data"]))
            image_index += 1
        elif "text" in part:
            print(part["text"])