# FLUX.2 [klein] 9B · Edit API

> Edycja obrazów sterowana promptem, przyjmująca maksymalnie 4 obrazy źródłowe i zwracająca od 1 do 4 zmodyfikowanych wyników

Edytuje istniejące obrazy na podstawie tekstowego `prompt` i `image_urls`, które przyjmuje maksymalnie 4 obrazy. Jeśli `image_size` zostanie pominięty, wynik zachowa rozmiar obrazu wejściowego. Wariant ten ma taki sam zakres `num_inference_steps` od 4 do 8, `num_images` od 1 do 4 oraz wyjście jpeg, png lub webp jak wariant tekst-do-obrazu. Można ustawić `seed`, aby uzyskać powtarzalne edycje.

- Model id: `flux-2/klein/9b/edit`
- Made by: Black Forest Labs
- Category: Image Editing
- Output: image
- Price per megapixel: $0.011 / megapixel (cheapest run $0.011 (11 API credits))
- Run: `POST https://api.doitong.com/v1/run/flux-2/klein/9b/edit`
- Quote: `POST https://api.doitong.com/v1/quote/flux-2/klein/9b/edit`
- Docs page: https://doitong.com/pl/developers/models/flux-2/klein/9b/edit

## Pricing

Price: **$0.011 / megapixel**. Price per megapixel: 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 $0.022 = 22 API credits (2 MP × $0.011).

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/flux-2/klein/9b/edit` 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 |  |  | Prompt opisujący edycje obrazu. |
| `seed` |  | integer \| null | no |  |  | Nadpisanie ziarna generowania; pominięcie pozwala generowaniu wybrać ziarno losowo. |
| `num_inference_steps` |  | integer | no | `4` | 4 – 8 | Liczba kroków inferencji do wykonania. |
| `image_size` |  | object {width, height} \| enum (string) \| null | no |  | `square_hd`, `square`, `portrait_4_3`, `portrait_16_9`, `landscape_4_3`, `landscape_16_9` | Wymiary wynikowego obrazu; po pominięciu odpowiadają wymiarom obrazu wejściowego. |
| `num_images` | `num_outputs` | integer | no | `1` | 1 – 4 | Liczba obrazów żądanych do wygenerowania. |
| `enable_safety_checker` |  | boolean | no | `true` |  | Kontrola bezpieczeństwa, która zastępuje obrazy oznaczone jako niebezpieczne czarnymi obrazami. Wartość true włącza kontrolę; false wyłącza ją wyłącznie dla autoryzowanych kont, natomiast żądania bez autoryzacji są sprawdzane niezależnie. |
| `output_format` |  | enum (string) | no | `png` | `jpeg`, `png`, `webp` | Format pliku wynikowego obrazu. |
| `image_urls` | `images` | array of image URL | yes |  |  | URL obrazów do edycji, maksymalnie 4 obrazy. |

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/flux-2/klein/9b/edit?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/flux-2/klein/9b/edit?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/flux-2/klein/9b/edit", 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": "flux-2/klein/9b/edit",
      "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": "flux-2/klein/9b/edit",
  "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": 22,
    "usd": "0.022",
    "charged": 22,
    "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} | Obrazy utworzone przez model. |
| `timings` | object |  |
| `seed` | integer | Ziarno generowania obrazu, zawierające wartość wybraną losowo, jeśli dane wejściowe nie zawierały ziarna; w przeciwnym razie powtarza podaną wartość. |
| `has_nsfw_concepts` | array of boolean | Wskazuje, czy w wygenerowanych obrazach występują treści NSFW. |
| `prompt` | string | Prompt używany podczas generowania obrazu. |

## Related models

- [FLUX.2 \[klein\] 4B](https://doitong.com/developers/models/flux-2/klein/4b.md) (`flux-2/klein/4b`): $0.005 / megapixel
- [FLUX.2 \[klein\] 4B Base](https://doitong.com/developers/models/flux-2/klein/4b/base.md) (`flux-2/klein/4b/base`): $0.009 / megapixel
- [FLUX.2 \[klein\] 9B](https://doitong.com/developers/models/flux-2/klein/9b.md) (`flux-2/klein/9b`): $0.006 / megapixel
- [FLUX.2 \[klein\] 9B Base](https://doitong.com/developers/models/flux-2/klein/9b/base.md) (`flux-2/klein/9b/base`): $0.011 / megapixel
- [FLUX.2 \[klein\] 4B Base · Edit](https://doitong.com/developers/models/flux-2/klein/4b/base/edit.md) (`flux-2/klein/4b/base/edit`): $0.009 / megapixel
- [FLUX.2 \[klein\] 4B · Edit](https://doitong.com/developers/models/flux-2/klein/4b/edit.md) (`flux-2/klein/4b/edit`): $0.01 / image
- [FLUX.2 \[klein\] 9B Base · Edit](https://doitong.com/developers/models/flux-2/klein/9b/base/edit.md) (`flux-2/klein/9b/base/edit`): $0.011 / megapixel
- [FLUX.1 Kontext \[pro\]](https://doitong.com/developers/models/flux-pro/kontext.md) (`flux-pro/kontext`): $0.04 / image

## Links

- HTML page: https://doitong.com/developers/models/flux-2/klein/9b/edit
- 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=flux-2/klein/9b/edit
- Errors: https://doitong.com/developers/docs/errors
- Model details as JSON: https://api.doitong.com/v1/models/flux-2/klein/9b/edit