# FLUX.3 Klein Image Editing API

> FLUX.3 Klein per l'editaziun cun maximalmain 10 referenzas e posiziunament facultativ d'objects cun rectangels d'incapsulaziun

Modifitgescha u cumpona maletgs a partir d'in prompt e da 1 fin a 10 referenzas en `image_urls`, a las qualas il prompt po far referenza tenor l'urden, per exempel al prim maletg. Fin a 32 `bounding_boxes` pon conservar, spustar, redimensiunar, allontanar u agiuntar objects, nominads en il prompt tras lur etichetta. L'expansiun dal prompt è activa per defaut. Il resultat cuntegna 1 fin a 4 maletgs en jpeg, png u webp.

- 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.com/v1/run/blackforestlabs/flux-3/klein/edit-image`
- Quote: `POST https://api.doitong.com/v1/quote/blackforestlabs/flux-3/klein/edit-image`
- Docs page: https://doitong.com/rm/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.com/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 |  |  | Scriva ina legenda cumpleta che descriva il maletg giavischà suenter l'ediziun, inditgond las referenzas tenor lur sequenza, sco il prim u il segund maletg. |
| `enable_prompt_expansion` |  | boolean | no | `true` |  | Expansiun dal prompt en ina legenda detagliada avant la generaziun, activada cun true. Per l'ediziun, la legenda sa basa sin ils maletgs da referenza. |
| `seed` |  | integer \| null | no |  |  | Semenza per maletgs reproducibels: in prompt ed ina semenza identics produceschan il medem maletg sch'è la versiun dal model invariada. |
| `num_images` | `num_outputs` | integer | no | `1` | 1 – 4 | Dumber da maletgs dumandà per la generaziun. |
| `enable_safety_checker` |  | boolean | no | `true` |  | Activaziun da la controlla da segirezza; true activa la controlla. |
| `output_format` |  | enum (string) | no | `png` | `jpeg`, `png`, `webp` | Format da datoteca dal maletg final. |
| `image_urls` | `images` | array of image URL | yes |  | 1 – 10 items | Maletgs da referenza utilisads per l'ediziun u la cumposiziun, limitads a 10. |
| `image_size` |  | object {width, height} \| enum (string) \| null | no |  | `square_hd`, `square`, `portrait_4_3`, `portrait_16_9`, `landscape_4_3`, `landscape_16_9` | Las dimensiuns d'output èn tenor standard quellas dal prim maletg da referenza, limitadas a 1 megapixel per pliras referenzas u scaladas a maximalmain 4 megapixel per ina suletta referenza. Dimensiuns explicitadas ston avair mintga vart tranter 256 e 4096 pixels. |
| `bounding_boxes` |  | array of object {label, description, box, source_image_index, source_box, target_box} \| null | no |  | ≤ 32 items | Layout d'objects opziunal per mantegnair, spustar, midar la grondezza u allontanar objects da referenza, u per plazzar objects novs. Las coordinatas cumenzan a (0, 0) en il chantun superiur sanester da mintga maletg; referenziescha las boxas cun labels en il prompt, sco `<dragon>`. |
| `bounding_boxes[].label` |  | string \| null | no |  | ≤ 64 characters | Label curta da l'object per la boxa, sco `dragon`; tenor standard è `obj_<n>`. Incluj `<dragon>` en il prompt per colliar ses pleds cun la boxa; boxas betg menziunadas en il prompt vegnan agiuntadas a la scena. |
| `bounding_boxes[].description` |  | string | yes |  | ≤ 500 characters | Object da renderisar en la boxa, inclus sia apparientscha. |
| `bounding_boxes[].box` |  | object {x_min, y_min, x_max, y_max} \| null | no |  |  | Plazzament d'output da l'object, che remplazza `source_box`/`target_box` e utilisescha il medem cumportament da plazzament sco text-to-image. |
| `bounding_boxes[].box.x_min` |  | number | yes |  | 0 – 1 | Limit sanester exprimì relativamain a la ladezza dal maletg, da 0 fin 1. |
| `bounding_boxes[].box.y_min` |  | number | yes |  | 0 – 1 | Limit superiur exprimì relativamain a l'autezza dal maletg, da 0 fin 1. |
| `bounding_boxes[].box.x_max` |  | number | yes |  | 0 – 1 | Limit dretg exprimì relativamain a la ladezza dal maletg, da 0 fin 1. |
| `bounding_boxes[].box.y_max` |  | number | yes |  | 0 – 1 | Limit inferiur exprimì relativamain a l'autezza dal maletg, da 0 fin 1. |
| `bounding_boxes[].source_image_index` |  | integer \| null | no |  | ≥ 0 | Selecziun da la funtauna da l'object: ometta per in object nov, u identifiescha ina referenza existenta tras ses index en `image_urls`, quintà da 0. |
| `bounding_boxes[].source_box` |  | object {x_min, y_min, x_max, y_max} \| null | no |  |  | Lieu da l'object entaifer il maletg da referenza; `source_image_index` sto medemamain vegnir furnì. |
| `bounding_boxes[].source_box.x_min` |  | number | yes |  | 0 – 1 | Limit sanester exprimì relativamain a la ladezza dal maletg, da 0 fin 1. |
| `bounding_boxes[].source_box.y_min` |  | number | yes |  | 0 – 1 | Limit superiur exprimì relativamain a l'autezza dal maletg, da 0 fin 1. |
| `bounding_boxes[].source_box.x_max` |  | number | yes |  | 0 – 1 | Limit dretg exprimì relativamain a la ladezza dal maletg, da 0 fin 1. |
| `bounding_boxes[].source_box.y_max` |  | number | yes |  | 0 – 1 | Limit inferiur exprimì relativamain a l'autezza dal maletg, da 0 fin 1. |
| `bounding_boxes[].target_box` |  | object {x_min, y_min, x_max, y_max} \| null | no |  |  | Boxa da plazzament d'output per l'object: per spustar u midar la grondezza dovran omaduas boxas vegnir furnidas, entant che per allontanar in object da referenza sto questa boxa vegnir laschada betg definida. |
| `bounding_boxes[].target_box.x_min` |  | number | yes |  | 0 – 1 | Limit sanester exprimì relativamain a la ladezza dal maletg, da 0 fin 1. |
| `bounding_boxes[].target_box.y_min` |  | number | yes |  | 0 – 1 | Limit superiur exprimì relativamain a l'autezza dal maletg, da 0 fin 1. |
| `bounding_boxes[].target_box.x_max` |  | number | yes |  | 0 – 1 | Limit dretg exprimì relativamain a la ladezza dal maletg, da 0 fin 1. |
| `bounding_boxes[].target_box.y_max` |  | number | yes |  | 0 – 1 | Limit inferiur exprimì relativamain a l'autezza dal maletg, da 0 fin 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.com/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.com/v1/requests/REQUEST_ID?wait=20" \
  -H "Authorization: Bearer $DOITONG_API_KEY"
```

### JavaScript

```javascript
const API = "https://api.doitong.com/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.com/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.com/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.com/v1/requests/req_8k2m4q7x1z9c3v5b6n0p2r4t",
    "cancel": "https://api.doitong.com/v1/requests/req_8k2m4q7x1z9c3v5b6n0p2r4t/cancel"
  }
}
```

### Output fields (`output`)

| Field | Type | Description |
|---|---|---|
| `images` | array of object {url, content_type, file_name, file_size, width, height} | Maletgs producids dal model. |
| `timings` | object | Infurmaziuns davart il temp dal process da generaziun. |
| `seed` | integer | Semenza da generaziun per il prim maletg. |
| `has_nsfw_concepts` | array of boolean | Inditgescha sche concepts NSFW cumparan en ils maletgs generads. |
| `prompt` | string | Prompt utilisà durant la generaziun dal maletg. |

## 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.com/v1/models/blackforestlabs/flux-3/klein/edit-image