> ## Documentation Index
> Fetch the complete documentation index at: https://docs.comfy.org/llms.txt
> Use this file to discover all available pages before exploring further.

# Use Aleph 2 with Comfy Router

> Call runway/aleph2 through Comfy Router: endpoint, request shape and the response Router returns.

API Reference for `runway/aleph2`, served by Comfy Router from Runway.

## 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:** `runway/aleph2`

**Endpoint:** `POST https://api.comfy.org/v2/models/runway/aleph2`

<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(
          "runway/aleph2",
          {
              "promptText": "recolor the scene in cool blue tones",
              "videoUri": "https://test-videos.co.uk/vids/bigbuckbunny/mp4/h264/360/Big_Buck_Bunny_360_10s_1MB.mp4",
          },
      )

  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("runway/aleph2", {
    promptText: "recolor the scene in cool blue tones",
    videoUri: "https://test-videos.co.uk/vids/bigbuckbunny/mp4/h264/360/Big_Buck_Bunny_360_10s_1MB.mp4",
  });

  console.log(data);
  ```

  ```bash cURL theme={null}
  curl https://api.comfy.org/v2/models/runway/aleph2 \
    -H "X-API-Key: $COMFY_API_KEY" \
    -H "Idempotency-Key: $(uuidgen)" \
    -H "Content-Type: application/json" \
    -d "{\"promptText\": \"recolor the scene in cool blue tones\", \"videoUri\": \"https://test-videos.co.uk/vids/bigbuckbunny/mp4/h264/360/Big_Buck_Bunny_360_10s_1MB.mp4\"}"
  ```
</CodeGroup>

## Schema

### Input

<ParamField body="contentModeration" type="object">
  Settings that affect the behavior of the content moderation system.
</ParamField>

<ParamField body="contentModeration.publicFigureThreshold" type="string">
  When set to `low`, the content moderation system will be less strict about preventing generations that include recognizable public figures.

  Possible values: `auto`, `low`
</ParamField>

<ParamField body="keyframes" type="object[]">
  Timed guidance images placed at specific points in the input video. Up to 5 keyframes.
</ParamField>

<ParamField body="model" type="string">
  Model to use for generation. On the Comfy Router route `POST /v2/models/runway/{model}` this field is supplied from the path and MUST NOT be sent; on the v1 `POST /proxy/runway/video_to_video` route it is required and constrained to the RunwayVideoToVideoModelEnum (`aleph2`).
</ParamField>

<ParamField body="promptImage" type="object[]">
  A list of up to 5 image keyframes for guiding the edit at specific points in the video.
</ParamField>

<ParamField body="promptImage[].position" type="`first`, `last` | object" required>
  The position in the output video where the image should apply.
</ParamField>

<ParamField body="promptImage[].uri" type="string" required>
  A HTTPS URL, Runway or data URI containing an encoded image.
</ParamField>

<ParamField body="promptText" type="string" required>
  A non-empty string up to 1000 characters describing what should appear in the output.
</ParamField>

<ParamField body="seed" type="integer">
  Random seed for generation.

  Range: `0` to `4294967295`

  Format: `int64`
</ParamField>

<ParamField body="videoUri" type="string" required>
  The input video to edit (HTTPS URL, Runway upload URI, or data URI). Must be 30 seconds or shorter.
</ParamField>

Generated from the schema Router serves at `GET /v2/models/runway/aleph2/openapi.json`, the same document it validates a call against before the request reaches the provider.

### Output

<ResponseField name="createdAt" type="string (date-time)" required>
  Task creation timestamp

  Format: `date-time`
</ResponseField>

<ResponseField name="id" type="string" required>
  Task ID
</ResponseField>

<ResponseField name="output" type="string[]">
  The finished generation's asset URLs — for `runway/gen4_turbo` and `runway/aleph2` each element is a VIDEO URL. Present once the task terminates successfully; this list IS the result.
</ResponseField>

<ResponseField name="progress" type="number">
  Float value between 0 and 1 representing the progress of the task. Only available if status is RUNNING.

  Range: `0` to `1`

  Format: `float`
</ResponseField>

<ResponseField name="status" type="string" required>
  Possible statuses for a Runway task.

  Possible values: `SUCCEEDED`, `RUNNING`, `FAILED`, `PENDING`, `CANCELLED`, `THROTTLED`
</ResponseField>

## Examples

### Input

```json theme={null}
{
  "promptText": "recolor the scene in cool blue tones",
  "videoUri": "https://test-videos.co.uk/vids/bigbuckbunny/mp4/h264/360/Big_Buck_Bunny_360_10s_1MB.mp4"
}
```

### Output

```json theme={null}
{
  "createdAt": "2027-01-01T00:00:00Z",
  "id": "5f7c1b28-9a03-4e61-8d2f-1b2c3d4e5f60",
  "output": [
    "https://example.invalid/runway/gen4_turbo/generated.mp4"
  ],
  "status": "SUCCEEDED"
}
```

## 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>