# FLUX.3 Klein Image Editing API

> FLUX.3 Klein 編輯器，支援最多 10 張參考影像及選用的邊界框物件放置

根據提示詞和 `image_urls` 中的 1 到 10 張參考影像編輯或合成影像，提示詞可依順序引用影像，例如第一張影像。最多 32 個 `bounding_boxes` 可依提示詞中的標籤名稱保留、移動、調整大小、移除或加入物件。預設啟用提示詞擴展。回傳 1 到 4 張 jpeg、png 或 webp 影像。

- 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-TW/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 |  |  | 撰寫完整說明，描述編輯後所需的圖像，並依序列識別參考圖像，例如第一張或第二張圖像。 |
| `enable_prompt_expansion` |  | boolean | no | `true` |  | 在生成前將提示詞展開為詳細說明；為 true 時啟用。編輯時，說明會以參考圖像為依據。 |
| `seed` |  | integer \| null | no |  |  | 可重現圖像的種子：模型版本不變時，相同的提示詞與種子會產生相同圖像。 |
| `num_images` | `num_outputs` | integer | no | `1` | 1 – 4 | 請求生成的圖像數量。 |
| `enable_safety_checker` |  | boolean | no | `true` |  | 安全檢查器啟用狀態；true 會啟用檢查。 |
| `output_format` |  | enum (string) | no | `png` | `jpeg`, `png`, `webp` | 生成圖像的檔案格式。 |
| `image_urls` | `images` | array of image URL | yes |  | 1 – 10 items | 用於編輯或構圖的參考圖像，最多 10 張。 |
| `image_size` |  | object {width, height} \| enum (string) \| null | no |  | `square_hd`, `square`, `portrait_4_3`, `portrait_16_9`, `landscape_4_3`, `landscape_16_9` | 輸出尺寸預設為第一張參考圖像的尺寸；多張參考圖像時上限為 1 百萬像素，單張參考圖像時則縮放至最多 4 百萬像素。明確指定的尺寸每邊必須介於 256 到 4096 像素之間。 |
| `bounding_boxes` |  | array of object {label, description, box, source_image_index, source_box, target_box} \| null | no |  | ≤ 32 items | 選用的物件配置，用於保留、移動、調整大小或移除參考物件，或放置新物件。座標從每張圖像左上角的 (0, 0) 開始；使用提示詞中的標籤（例如 `<dragon>`）參照方框。 |
| `bounding_boxes[].label` |  | string \| null | no |  | ≤ 64 characters | 方框的簡短物件標籤，例如 `dragon`；預設值為 `obj_<n>`。在提示詞中加入 `<dragon>`，即可將其文字與方框關聯；提示詞未提及的方框會加入場景。 |
| `bounding_boxes[].description` |  | string | yes |  | ≤ 500 characters | 要在方框內渲染的物件，包括其外觀。 |
| `bounding_boxes[].box` |  | object {x_min, y_min, x_max, y_max} \| null | no |  |  | 物件的輸出位置，取代 `source_box`/`target_box`，並使用與文字生成圖像相同的位置行為。 |
| `bounding_boxes[].box.x_min` |  | number | yes |  | 0 – 1 | 相對於圖像寬度表示的左邊界，範圍為 0 到 1。 |
| `bounding_boxes[].box.y_min` |  | number | yes |  | 0 – 1 | 相對於圖像高度表示的上邊界，範圍為 0 到 1。 |
| `bounding_boxes[].box.x_max` |  | number | yes |  | 0 – 1 | 相對於圖像寬度表示的右邊界，範圍為 0 到 1。 |
| `bounding_boxes[].box.y_max` |  | number | yes |  | 0 – 1 | 相對於圖像高度表示的下邊界，範圍為 0 到 1。 |
| `bounding_boxes[].source_image_index` |  | integer \| null | no |  | ≥ 0 | 物件來源選擇：新物件請省略；或使用其在 `image_urls` 中從 0 開始計算的索引識別現有參考物件。 |
| `bounding_boxes[].source_box` |  | object {x_min, y_min, x_max, y_max} \| null | no |  |  | 物件在參考圖像中的位置；也必須提供 `source_image_index`。 |
| `bounding_boxes[].source_box.x_min` |  | number | yes |  | 0 – 1 | 相對於圖像寬度表示的左邊界，範圍為 0 到 1。 |
| `bounding_boxes[].source_box.y_min` |  | number | yes |  | 0 – 1 | 相對於圖像高度表示的上邊界，範圍為 0 到 1。 |
| `bounding_boxes[].source_box.x_max` |  | number | yes |  | 0 – 1 | 相對於圖像寬度表示的右邊界，範圍為 0 到 1。 |
| `bounding_boxes[].source_box.y_max` |  | number | yes |  | 0 – 1 | 相對於圖像高度表示的下邊界，範圍為 0 到 1。 |
| `bounding_boxes[].target_box` |  | object {x_min, y_min, x_max, y_max} \| null | no |  |  | 物件的輸出位置方框：移動或調整大小需要兩個方框；移除參考物件時則必須不設定此方框。 |
| `bounding_boxes[].target_box.x_min` |  | number | yes |  | 0 – 1 | 相對於圖像寬度表示的左邊界，範圍為 0 到 1。 |
| `bounding_boxes[].target_box.y_min` |  | number | yes |  | 0 – 1 | 相對於圖像高度表示的上邊界，範圍為 0 到 1。 |
| `bounding_boxes[].target_box.x_max` |  | number | yes |  | 0 – 1 | 相對於圖像寬度表示的右邊界，範圍為 0 到 1。 |
| `bounding_boxes[].target_box.y_max` |  | number | yes |  | 0 – 1 | 相對於圖像高度表示的下邊界，範圍為 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} | 模型生成的圖像。 |
| `timings` | object | 生成程序的計時資訊。 |
| `seed` | integer | 第一張圖像的生成種子。 |
| `has_nsfw_concepts` | array of boolean | 指出生成的圖像中是否出現 NSFW 概念。 |
| `prompt` | string | 圖像生成期間使用的提示詞。 |

## 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