# FLUX.3 Klein Image Editing API

> FLUX.3 Klein 编辑器，支持最多 10 张参考图和可选的边界框对象放置

根据提示词和 `image_urls` 中的 1 到 10 张参考图编辑或合成图像，提示词可按顺序引用参考图，例如第一张图。最多 32 个 `bounding_boxes` 可用于保留、移动、调整大小、移除或添加对象，提示词通过标签命名对象。默认开启提示词扩展。返回 1 到 4 张 jpeg、png 或 webp 图像。

- Model id: `blackforestlabs/flux-3/klein/edit-image`
- Made by: Black Forest Labs
- Category: Image Editing
- Output: image
- Price per run: from $0.008 / run of output image (cheapest run $0.008 (8 API credits))
- Run: `POST https://api.doitong.ru/v1/run/blackforestlabs/flux-3/klein/edit-image`
- Quote: `POST https://api.doitong.ru/v1/quote/blackforestlabs/flux-3/klein/edit-image`
- Docs page: https://doitong.com/zh/developers/models/blackforestlabs/flux-3/klein/edit-image

## Pricing

Price: **from $0.008 / run of output image** (the lowest tier; the quote prices your exact input). Price per run: the input files are measured before the run (length, resolution, frame rate). The quote measures the same files and is exactly what the run charges.

The full example input below costs $0.009 = 9 API credits (1 run × $0.009).

Prices are the upstream price in USD, paid from the API balance in API credits (1000 API credits = 1 USD). `POST https://api.doitong.ru/v1/quote/blackforestlabs/flux-3/klein/edit-image` with the same JSON body returns the exact price for that input; the quote is exactly what a run charges. Invalid input is never charged and failed or canceled requests are refunded automatically.

## Input parameters

Send either the canonical name or the native field name (not both). Canonical names are the same across models.

| Parameter | Canonical name | Type | Required | Default | Allowed values / range | Description |
|---|---|---|---|---|---|---|
| `prompt` |  | string | yes |  |  | 完整撰写编辑后所需图像的说明文字，并按顺序标识参考对象，例如第一张或第二张图像。 |
| `enable_prompt_expansion` |  | boolean | no | `true` |  | 生成前将提示词扩展为详细说明文字，值为 true 时启用。编辑时，说明文字基于参考图像生成。 |
| `seed` |  | integer \| null | no |  |  | 用于生成可复现图像的种子：模型版本不变时，相同的提示词和种子会生成相同图像。 |
| `num_images` | `num_outputs` | integer | no | `1` | 1 – 4 | 请求生成的图像数量。 |
| `enable_safety_checker` |  | boolean | no | `true` |  | 安全检查器激活状态；true 启用检查。 |
| `output_format` |  | enum (string) | no | `png` | `jpeg`, `png`, `webp` | 结果图像的文件格式。 |
| `image_urls` | `images` | array of image URL | yes |  | 1 – 10 items | 用于编辑或合成的参考图像，最多 10 张。 |
| `image_size` |  | object {width, height} \| enum (string) \| null | no |  | `square_hd`, `square`, `portrait_4_3`, `portrait_16_9`, `landscape_4_3`, `landscape_16_9` | 输出尺寸默认采用第一张参考图像的尺寸；多个参考图像时上限为 1 百万像素，单个参考图像时缩放至最多 4 百万像素。明确指定的尺寸每边必须介于 256 和 4096 像素之间。 |
| `bounding_boxes` |  | array of object {label, description, box, source_image_index, source_box, target_box} \| null | no |  | ≤ 32 items | 可选对象布局，用于保留、移动、调整大小或移除参考对象，或放置新对象。坐标从每张图像左上角的 (0, 0) 开始；使用提示词中的标签引用框，例如 `<dragon>`。 |
| `bounding_boxes[].label` |  | string \| null | no |  | ≤ 64 characters | 框的简短对象标签，例如 `dragon`；默认值为 `obj_<n>`。在提示词中加入 `<dragon>`，将相关文字与该框关联；提示词中未提及的框会添加到场景中。 |
| `bounding_boxes[].description` |  | string | yes |  | ≤ 500 characters | 要在框内渲染的对象，包括其外观。 |
| `bounding_boxes[].box` |  | object {x_min, y_min, x_max, y_max} \| null | no |  |  | 对象的输出位置，替换 `source_box`/`target_box`，并使用与文生图相同的位置行为。 |
| `bounding_boxes[].box.x_min` |  | number | yes |  | 0 – 1 | 相对于图像宽度表示的左边界，范围为 0 到 1。 |
| `bounding_boxes[].box.y_min` |  | number | yes |  | 0 – 1 | 相对于图像高度表示的上边界，范围为 0 到 1。 |
| `bounding_boxes[].box.x_max` |  | number | yes |  | 0 – 1 | 相对于图像宽度表示的右边界，范围为 0 到 1。 |
| `bounding_boxes[].box.y_max` |  | number | yes |  | 0 – 1 | 相对于图像高度表示的下边界，范围为 0 到 1。 |
| `bounding_boxes[].source_image_index` |  | integer \| null | no |  | ≥ 0 | 对象源选择：省略表示新对象，或通过其在 `image_urls` 中的索引标识现有参考对象，索引从 0 开始。 |
| `bounding_boxes[].source_box` |  | object {x_min, y_min, x_max, y_max} \| null | no |  |  | 对象在参考图像中的位置；还必须提供 `source_image_index`。 |
| `bounding_boxes[].source_box.x_min` |  | number | yes |  | 0 – 1 | 相对于图像宽度表示的左边界，范围为 0 到 1。 |
| `bounding_boxes[].source_box.y_min` |  | number | yes |  | 0 – 1 | 相对于图像高度表示的上边界，范围为 0 到 1。 |
| `bounding_boxes[].source_box.x_max` |  | number | yes |  | 0 – 1 | 相对于图像宽度表示的右边界，范围为 0 到 1。 |
| `bounding_boxes[].source_box.y_max` |  | number | yes |  | 0 – 1 | 相对于图像高度表示的下边界，范围为 0 到 1。 |
| `bounding_boxes[].target_box` |  | object {x_min, y_min, x_max, y_max} \| null | no |  |  | 对象的输出位置框：移动或调整大小需要同时提供两个框；移除参考对象时必须不设置此框。 |
| `bounding_boxes[].target_box.x_min` |  | number | yes |  | 0 – 1 | 相对于图像宽度表示的左边界，范围为 0 到 1。 |
| `bounding_boxes[].target_box.y_min` |  | number | yes |  | 0 – 1 | 相对于图像高度表示的上边界，范围为 0 到 1。 |
| `bounding_boxes[].target_box.x_max` |  | number | yes |  | 0 – 1 | 相对于图像宽度表示的右边界，范围为 0 到 1。 |
| `bounding_boxes[].target_box.y_max` |  | number | yes |  | 0 – 1 | 相对于图像高度表示的下边界，范围为 0 到 1。 |

File parameters (`images`) take a public `https://` URL, a `data:` URI up to 10 MB, or the `file_url` of an upload from `POST /files`.

## Example input

Required parameters only:

```json
{
  "prompt": "A red fox trots through fresh snow at sunrise, soft golden light, shallow depth of field",
  "images": [
    "https://content.doitong.com/images/showcase/v3/gen_fox_cartoon.jpg"
  ]
}
```

A fuller example:

```json
{
  "prompt": "A red fox trots through fresh snow at sunrise, soft golden light, shallow depth of field",
  "image_urls": [
    "https://content.doitong.com/images/showcase/v3/gen_fox_cartoon.jpg"
  ]
}
```

## Run it

Set `DOITONG_API_KEY` to a key from https://doitong.com/developers/dashboard#keys. `?wait=20` returns the finished request in the same call when it is ready within 20 seconds; otherwise poll `GET /requests/{id}` (it also accepts `?wait=`), or pass `webhook_url`.

### curl

```bash
# Run the model; wait up to 20 s for the finished result in the same call
curl -X POST "https://api.doitong.ru/v1/run/blackforestlabs/flux-3/klein/edit-image?wait=20" \
  -H "Authorization: Bearer $DOITONG_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "prompt": "A red fox trots through fresh snow at sunrise, soft golden light, shallow depth of field",
    "image_urls": [
      "https://content.doitong.com/images/showcase/v3/gen_fox_cartoon.jpg"
    ]
  }'

# Still "queued" or "running"? Poll with the id from the response:
curl "https://api.doitong.ru/v1/requests/REQUEST_ID?wait=20" \
  -H "Authorization: Bearer $DOITONG_API_KEY"
```

### JavaScript

```javascript
const API = "https://api.doitong.ru/v1";
const headers = {
  "Authorization": "Bearer " + process.env.DOITONG_API_KEY,
  "Content-Type": "application/json",
};

// Run the model; wait up to 20 s for the finished result in the same call
let res = await fetch(API + "/run/blackforestlabs/flux-3/klein/edit-image?wait=20", {
  method: "POST",
  headers,
  body: JSON.stringify({
    "prompt": "A red fox trots through fresh snow at sunrise, soft golden light, shallow depth of field",
    "image_urls": [
      "https://content.doitong.com/images/showcase/v3/gen_fox_cartoon.jpg"
    ]
  }),
});
let request = await res.json();
if (!res.ok) throw new Error(request.error.code + ": " + request.error.message);

// Not finished yet: long-poll until it is
while (request.status === "queued" || request.status === "running") {
  res = await fetch(API + "/requests/" + request.id + "?wait=20", { headers });
  request = await res.json();
}
if (request.status !== "succeeded") throw new Error(JSON.stringify(request.error));
console.log(request.outputs.map((o) => o.url), request.cost.credits + " API credits ($" + request.cost.usd + ")");
```

### Python

```python
import os
import requests

API = "https://api.doitong.ru/v1"
headers = {"Authorization": "Bearer " + os.environ["DOITONG_API_KEY"]}

payload = {
    "prompt": "A red fox trots through fresh snow at sunrise, soft golden light, shallow depth of field",
    "image_urls": [
        "https://content.doitong.com/images/showcase/v3/gen_fox_cartoon.jpg",
    ],
}

# Run the model; wait up to 20 s for the finished result in the same call
r = requests.post(API + "/run/blackforestlabs/flux-3/klein/edit-image", params={"wait": 20}, json=payload, headers=headers)
request = r.json()
if not r.ok:
    raise RuntimeError(request["error"]["code"] + ": " + request["error"]["message"])

# Not finished yet: long-poll until it is
while request["status"] in ("queued", "running"):
    request = requests.get(API + "/requests/" + request["id"], params={"wait": 20}, headers=headers).json()
if request["status"] != "succeeded":
    raise RuntimeError(request["error"])
print([o["url"] for o in request["outputs"]], request["cost"]["credits"], "API credits", "$" + request["cost"]["usd"])
```

### MCP

The MCP server at `https://api.doitong.ru/v1/mcp` exposes the tools `search_models`, `get_model`, `quote`, `run`, `get_request`, `cancel_request`, `list_requests`, `create_upload` and `get_account`. A `run` call for this model:

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "run",
    "arguments": {
      "model_id": "blackforestlabs/flux-3/klein/edit-image",
      "input": {
        "prompt": "A red fox trots through fresh snow at sunrise, soft golden light, shallow depth of field",
        "image_urls": [
          "https://content.doitong.com/images/showcase/v3/gen_fox_cartoon.jpg"
        ]
      },
      "wait_seconds": 20
    }
  }
}
```

## Response

Every call returns a request object. `status` is one of `queued`, `running`, `succeeded`, `failed`, `canceled`. `outputs` lists the generated files with URLs on our storage (kept forever, or 7 days with `?storage=temporary`; `storage` says which); `output` is the model's own result object with the same URLs.

```json
{
  "id": "req_8k2m4q7x1z9c3v5b6n0p2r4t",
  "object": "request",
  "model": "blackforestlabs/flux-3/klein/edit-image",
  "status": "succeeded",
  "created_at": "2026-10-20T12:00:00Z",
  "started_at": "2026-10-20T12:00:02Z",
  "completed_at": "2026-10-20T12:00:09Z",
  "queue_position": null,
  "cost": {
    "credits": 9,
    "usd": "0.009",
    "charged": 9,
    "refunded": 0
  },
  "input": {
    "prompt": "A red fox trots through fresh snow at sunrise, soft golden light, shallow depth of field",
    "image_urls": [
      "https://content.doitong.com/images/showcase/v3/gen_fox_cartoon.jpg"
    ]
  },
  "output": {
    "images": [
      {
        "url": "https://content.doitong.com/dev-api/2026/10/20/req_8k2m4q7x1z9c3v5b6n0p2r4t/0-output.jpeg",
        "content_type": "image/jpeg",
        "file_name": "0-output.jpeg",
        "file_size": 1843200,
        "width": 1024,
        "height": 768
      }
    ],
    "timings": {},
    "seed": 42,
    "has_nsfw_concepts": [
      false
    ],
    "prompt": "string"
  },
  "outputs": [
    {
      "type": "image",
      "url": "https://content.doitong.com/dev-api/2026/10/20/req_8k2m4q7x1z9c3v5b6n0p2r4t/0-output.jpeg",
      "content_type": "image/jpeg",
      "file_size": 1843200,
      "width": 1024,
      "height": 768,
      "stored": true
    }
  ],
  "error": null,
  "metrics": {
    "inference_seconds": 6.8
  },
  "urls": {
    "self": "https://api.doitong.ru/v1/requests/req_8k2m4q7x1z9c3v5b6n0p2r4t",
    "cancel": "https://api.doitong.ru/v1/requests/req_8k2m4q7x1z9c3v5b6n0p2r4t/cancel"
  }
}
```

### Output fields (`output`)

| Field | Type | Description |
|---|---|---|
| `images` | array of object {url, content_type, file_name, file_size, width, height} | 模型生成的图像。 |
| `timings` | object | 生成过程的计时信息。 |
| `seed` | integer | 第一张图像的生成种子。 |
| `has_nsfw_concepts` | array of boolean | 指示生成的图像中是否出现 NSFW 概念。 |
| `prompt` | string | 图像生成期间使用的提示词。 |

## Related models

- [FLUX.3 Klein](https://doitong.com/developers/models/blackforestlabs/flux-3/klein/text-to-image.md) (`blackforestlabs/flux-3/klein/text-to-image`): from $0.008 / run of output image
- [FLUX.1 Kontext \[pro\]](https://doitong.com/developers/models/flux-pro/kontext.md) (`flux-pro/kontext`): $0.04 / image
- [GPT Image 2.5 Edit](https://doitong.com/developers/models/openai/gpt-image-2.5/flare/edit.md) (`openai/gpt-image-2.5/flare/edit`): from $0.12 / image
- [Nano Banana 2 Edit](https://doitong.com/developers/models/nano-banana-2/edit.md) (`nano-banana-2/edit`): from $0.06 / image
- [Nano Banana Pro Edit](https://doitong.com/developers/models/nano-banana-pro/edit.md) (`nano-banana-pro/edit`): from $0.15 / image
- [Qwen Image 3 Edit](https://doitong.com/developers/models/alibaba/qwen-image-3/edit.md) (`alibaba/qwen-image-3/edit`): from $0.04 / image
- [Seedream 5.0 Pro Edit](https://doitong.com/developers/models/bytedance/seedream/v5/pro/edit.md) (`bytedance/seedream/v5/pro/edit`): from $0.0675 / run of output image
- [FLUX 2 Edit](https://doitong.com/developers/models/flux-2/edit.md) (`flux-2/edit`): $0.012 / megapixel

## Links

- HTML page: https://doitong.com/developers/models/blackforestlabs/flux-3/klein/edit-image
- All models and guides for AI agents: https://doitong.com/developers/llms.txt
- OpenAPI 3.1 with this model's typed request body: https://doitong.com/developers/openapi.json?model=blackforestlabs/flux-3/klein/edit-image
- Errors: https://doitong.com/developers/docs/errors
- Model details as JSON: https://api.doitong.ru/v1/models/blackforestlabs/flux-3/klein/edit-image