> ## Documentation Index
> Fetch the complete documentation index at: https://dripart-matt-sdk-0-3-0-run-kind.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Use FLUX 2 Pro with Comfy Router

> Call bfl/flux-2-pro through Comfy Router: endpoint, request shape and the response Router returns.

API Reference for `bfl/flux-2-pro`, served by Comfy Router from Black Forest Labs.

## Quick start

Create a key in [your Comfy workspace](https://platform.comfy.org/profile/api-keys) and export it as `COMFY_API_KEY`. The Python and TypeScript snippets use the Comfy SDKs (`pip install comfy-sdk`, `npm install @comfyorg/sdk`); the cURL snippet is the same call over raw HTTP.

**Model ID:** `bfl/flux-2-pro`

**Endpoint:** `POST https://api.comfy.org/v2/models/bfl/flux-2-pro`

<Tabs>
  <Tab title="Wait for the result">
    <CodeGroup>
      ```python Python theme={null}
      from comfy_sdk import Comfy

      # Reads COMFY_API_KEY from the environment.
      # The SDK automatically creates an idempotency key and reuses it for automatic retries.
      with Comfy() as client:
          result = client.models.run(
              "bfl/flux-2-pro",
              {
                  "prompt": "A single red maple leaf on a plain white background.",
              },
          )

      print(result)
      ```

      ```typescript TypeScript theme={null}
      import { comfy } from "@comfyorg/sdk";

      // Reads COMFY_API_KEY from the environment.
      // The SDK automatically creates an idempotency key and reuses it for automatic retries.
      const { data } = await comfy.models.run("bfl/flux-2-pro", {
        prompt: "A single red maple leaf on a plain white background.",
      });

      console.log(data);
      ```

      ```bash cURL theme={null}
      curl https://api.comfy.org/v2/models/bfl/flux-2-pro \
        -H "X-API-Key: $COMFY_API_KEY" \
        -H "Idempotency-Key: $(uuidgen)" \
        -H "Content-Type: application/json" \
        -d "{\"prompt\": \"A single red maple leaf on a plain white background.\"}"
      ```
    </CodeGroup>
  </Tab>

  <Tab title="Queue and collect later">
    <Note>
      Queued delivery is rolling out per workspace. Until yours is enabled, the submit route answers `403` with `X-Comfy-Error-Type: not_enabled`. Nothing about the request is wrong, and the same body works through the synchronous route in the meantime.
    </Note>

    The same body, sent to `POST https://api.comfy.org/v2/models/bfl/flux-2-pro/requests`. Router answers `201` with a `request_id` as soon as the run is admitted, and the result is collected once it is ready, from this process or another one. [Queued delivery](/development/comfy-router/queue) walks through status, cancellation and collection.

    <CodeGroup>
      ```python Python theme={null}
      from comfy_sdk import Comfy

      # Reads COMFY_API_KEY from the environment.
      # Each submit() call mints its own Idempotency-Key and reuses it for automatic retries.
      with Comfy() as client:
          handle = client.models.submit(
              "bfl/flux-2-pro",
              {
                  "prompt": "A single red maple leaf on a plain white background.",
              },
          )
          print("request_id:", handle.request_id)  # with the model ID, all another process needs

          # Poll until the request completes, waiting the Retry-After the server names.
          for update in handle.iter_events():
              print(update.status, update.queue_position)

          # The provider's own payload, the same value models.run() returns.
          # A request that failed or was cancelled raises the typed Router error here.
          result = handle.get()

      print(result)
      ```

      ```typescript TypeScript theme={null}
      import { comfy } from "@comfyorg/sdk";

      // Reads COMFY_API_KEY from the environment.
      // Each submit() call mints its own Idempotency-Key and reuses it for automatic retries.
      const handle = await comfy.models.submit("bfl/flux-2-pro", {
        prompt: "A single red maple leaf on a plain white background.",
      });
      console.log("requestId:", handle.requestId); // with the model ID, all another process needs

      // Poll until the request completes, waiting the Retry-After the server names.
      for await (const update of handle.events()) {
        console.log(update.status, update.queuePosition);
      }

      // The same result models.run() returns. A request that failed or was cancelled rejects here.
      const result = await handle.get();

      console.log(result.data);
      ```

      ```bash cURL theme={null}
      # 1. Submit. Router answers 201 with request_id, status_url, response_url and cancel_url.
      curl https://api.comfy.org/v2/models/bfl/flux-2-pro/requests \
        -H "X-API-Key: $COMFY_API_KEY" \
        -H "Idempotency-Key: $(uuidgen)" \
        -H "Content-Type: application/json" \
        -d "{\"prompt\": \"A single red maple leaf on a plain white background.\"}"

      # 2. Poll until status is COMPLETED, waiting the Retry-After seconds each response names.
      REQUEST_ID="<request_id from the 201 body>"
      curl -i https://api.comfy.org/v2/models/bfl/flux-2-pro/requests/$REQUEST_ID/status \
        -H "X-API-Key: $COMFY_API_KEY"

      # 3. Collect. 200 with the model's native output, 202 with the status body while it is still running.
      curl https://api.comfy.org/v2/models/bfl/flux-2-pro/requests/$REQUEST_ID \
        -H "X-API-Key: $COMFY_API_KEY"
      ```
    </CodeGroup>
  </Tab>
</Tabs>

## Schema

### Input

<ParamField body="height" type="integer" default="1024">
  Height of the image.

  Range: `256` to `2048`
</ParamField>

<ParamField body="input_image" type="string">
  Base64 encoded image for image-to-image generation.
</ParamField>

<ParamField body="input_image_2" type="string">
  Base64 encoded image for image-to-image generation.
</ParamField>

<ParamField body="input_image_3" type="string">
  Base64 encoded image for image-to-image generation.
</ParamField>

<ParamField body="input_image_4" type="string">
  Base64 encoded image for image-to-image generation.
</ParamField>

<ParamField body="input_image_5" type="string">
  Base64 encoded image for image-to-image generation.
</ParamField>

<ParamField body="input_image_6" type="string">
  Base64 encoded image for image-to-image generation.
</ParamField>

<ParamField body="input_image_7" type="string">
  Base64 encoded image for image-to-image generation.
</ParamField>

<ParamField body="input_image_8" type="string">
  Base64 encoded image for image-to-image generation.
</ParamField>

<ParamField body="input_image_9" type="string">
  Base64 encoded image for image-to-image generation.
</ParamField>

<ParamField body="output_format" type="string" default="&#x22;jpeg&#x22;">
  Output format for the generated image.

  Possible values: `jpeg`, `png`
</ParamField>

<ParamField body="prompt" type="string" required>
  Text description of the image to generate.
</ParamField>

<ParamField body="prompt_upsampling" type="boolean" default="true">
  Automatically modify prompt for generation.
</ParamField>

<ParamField body="safety_tolerance" type="integer" default="2">
  Moderation tolerance level (Flux 2 Max only).

  Range: `0` to `5`
</ParamField>

<ParamField body="seed" type="integer">
  Seed for reproducibility.
</ParamField>

<ParamField body="width" type="integer" default="1024">
  Width of the image.

  Range: `256` to `2048`
</ParamField>

Generated from the schema Router serves at `GET /v2/models/bfl/flux-2-pro/openapi.json`, the same document it validates a call against before the request reaches the provider.

### Output

<ResponseField name="cost" type="number">
  Provider-reported cost in credits, populated once the task is Ready.

  Format: `float`
</ResponseField>

<ResponseField name="id" type="string" required>
  BFL task identifier.
</ResponseField>

<ResponseField name="progress" type="number">
  Optional generation progress reported by BFL.

  Range: `0` to `1`

  Format: `float`
</ResponseField>

<ResponseField name="result" type="object" required>
  The finished generation. Not nullable here: this component's `required` entry is a promise that a `200` carries the result, and a nullable `result` would reduce it to a key-presence check.
</ResponseField>

<ResponseField name="result.cost" type="number">
  Provider-reported cost of the generation. This is BFL's number, not the Comfy charge.

  Format: `double`
</ResponseField>

<ResponseField name="result.duration" type="number">
  Provider-reported generation duration in seconds.

  Format: `double`
</ResponseField>

<ResponseField name="result.end_time" type="number">
  Provider-reported completion time of the generation, in seconds since the Unix epoch. `double` for the same reason as `start_time`.

  Format: `double`
</ResponseField>

<ResponseField name="result.prompt" type="string">
  The prompt the generation actually ran, after any prompt upsampling.
</ResponseField>

<ResponseField name="result.sample" type="string (uri)">
  Signed URL for the generated asset. Router re-hosts the asset onto Comfy storage and rewrites this field, so it is normally a Comfy-hosted URL valid for up to 24 hours - signed for 24 hours when minted, and replayed from a 23-hour memo, so a later poll can hand back one with as little as an hour left; a leaf whose re-host could not be performed keeps BFL's own short-lived delivery URL instead - roughly two hours for video, roughly ten minutes for images. Either way the link expires, so download the asset rather than storing the URL.

  Format: `uri`
</ResponseField>

<ResponseField name="result.seed" type="integer">
  The seed the generation used, whether supplied or chosen by the provider. Declared `int64` because BFL returns seeds above 2^31 (e.g. 2784347701), which an unformatted `integer` generates as a 32-bit field in many SDK generators.

  Format: `int64`
</ResponseField>

<ResponseField name="result.start_time" type="number">
  Provider-reported start time of the generation, in seconds since the Unix epoch. `double`, not `float`: float32 spacing near a present-day epoch value is \~128 seconds, which collapses a whole generation's span to a single decoded value.

  Format: `double`
</ResponseField>

<ResponseField name="status" type="string" required>
  Task status: Pending, Reasoning, Generating, Ready, Request Moderated, Content Moderated, Error, or Task not found.
</ResponseField>

## Examples

### Input

```json theme={null}
{
  "prompt": "A single red maple leaf on a plain white background."
}
```

### Output

```json theme={null}
{
  "cost": null,
  "id": "b2e0c1a4-0f2f-4a55-9f2e-2f9a1c0d4e77",
  "progress": null,
  "result": {
    "cost": null,
    "duration": 3.4,
    "end_time": 1767225603.4,
    "prompt": "A watercolor painting of a lighthouse at dawn, soft light on the water",
    "sample": "https://example.invalid/bfl/flux-pro-1.1/sample.png",
    "seed": 2784347701,
    "start_time": 1767225600
  },
  "status": "Ready"
}
```

## Before you ship

The SDKs create an `Idempotency-Key` and reuse it for automatic retries. For manual retries, reuse the original key. Router can hold the connection for up to 10 minutes.

When a request fails, Router sends an `X-Comfy-Error-Type` response header explaining why. A `422` means Router rejected the input before calling the provider. Download generated assets promptly because [result URLs can expire](/development/comfy-router/reference#result-assets).

<CardGroup cols={3}>
  <Card title="Headers" icon="list" href="/development/comfy-router/headers">
    Authentication, idempotency, request IDs, error buckets, retry pacing, spend limits.
  </Card>

  <Card title="Using the Router API" icon="code" href="/development/comfy-router/api">
    Model discovery, validation errors, retries, and billing.
  </Card>

  <Card title="Limitations" icon="triangle-exclamation" href="/development/comfy-router/limitations">
    What Router does not do today, and what to use instead.
  </Card>
</CardGroup>