> ## Documentation Index
> Fetch the complete documentation index at: https://dripart-codex-simplify-get-started.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Use FLUX Video Upscale with Comfy Router

> Python, TypeScript and cURL snippets for upscaling a video with FLUX Video Upscale over HTTP through Comfy Router, plus the request fields and the result shape

API Reference for FLUX Video Upscale. FLUX Video Upscale is Black Forest Labs' video upscaler: send a video, get a higher-resolution version back.

## 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/video-upscale-v1`

**Endpoint:** `POST https://api.comfy.org/v2/models/bfl/video-upscale-v1`

<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/video-upscale-v1",
          {
              "input_video": "https://your-host.example/clip.mp4",
              "upscale_factor": 2,
              "creativity": 1,
          },
      )

  print("video:", result["result"]["sample"])
  ```

  ```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.
  type Result = { result: { sample: string } };
  const { data } = await comfy.models.run<Result>("bfl/video-upscale-v1", {
    input_video: "https://your-host.example/clip.mp4",
    upscale_factor: 2,
    creativity: 1,
  });

  console.log("video:", data.result.sample);
  ```

  ```bash cURL theme={null}
  curl https://api.comfy.org/v2/models/bfl/video-upscale-v1 \
    -H "X-API-Key: $COMFY_API_KEY" \
    -H "Idempotency-Key: $(uuidgen)" \
    -H "Content-Type: application/json" \
    -d "{\"input_video\": \"https://your-host.example/clip.mp4\", \"upscale_factor\": 2, \"creativity\": 1}"
  ```
</CodeGroup>

## Schema

### Input

<ParamField body="creativity" type="integer" default="1">
  0 preserves the source precisely and sharpens it; 1 allows creative detail enhancement, which does not strictly preserve faces or products.

  Range: `0` to `1`
</ParamField>

<ParamField body="input_video" type="string" required>
  Video to upscale, either an HTTP(S) URL or a base64-encoded MP4. At most 20 seconds of source footage and 50MB.
</ParamField>

<ParamField body="prompt" type="string">
  Optional description of the clip's content, steering the enhanced detail. Leave empty for a neutral upscale.
</ParamField>

<ParamField body="safety_tolerance" type="integer" default="2">
  Tolerance level for prompt and output frame moderation, 0 being most strict.

  Range: `0` to `4`
</ParamField>

<ParamField body="upscale_factor" type="number" default="2">
  Output scaling relative to the source resolution. The output preserves the source aspect ratio and is capped at roughly 14.4 megapixels per frame, so very large sources scale by less than the requested factor.

  Range: `1.5` to `3`

  Format: `float`
</ParamField>

<ParamField body="webhook_secret" type="string">
  Optional secret for webhook signature verification.
</ParamField>

<ParamField body="webhook_url" type="string (uri)">
  URL to receive webhook notifications.

  Format: `uri`
</ParamField>

Generated from the schema Router serves at `GET /v2/models/bfl/video-upscale-v1/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}
{
  "input_video": "https://your-host.example/clip.mp4",
  "upscale_factor": 2,
  "creativity": 1
}
```

### Output

```json theme={null}
{
  "id": "0a1b2c3d-...",
  "status": "Ready",
  "result": {
    "sample": "https://.../upscaled.mp4"
  }
}
```

`result.sample` is normally a Comfy-hosted signed URL, valid for up to 24 hours from creation. A replay can return an older URL, and an asset that could not be re-hosted keeps its shorter-lived provider URL. Download the MP4 promptly rather than storing the link.

## 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>