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

# Use Veo 3.1 Fast Generate 001 with Comfy Router

> Call veo/veo-3.1-fast-generate-001 through Comfy Router: endpoint, request shape and the response Router returns.

API Reference for `veo/veo-3.1-fast-generate-001`, served by Comfy Router from Veo.

## 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:** `veo/veo-3.1-fast-generate-001`

**Endpoint:** `POST https://api.comfy.org/v2/models/veo/veo-3.1-fast-generate-001`

<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(
              "veo/veo-3.1-fast-generate-001",
              {
                  "instances": [
                      {
                          "prompt": "a single red maple leaf falling onto still water, slow motion",
                      },
                  ],
                  "parameters": {
                      "durationSeconds": 4,
                      "generateAudio": False,
                      "sampleCount": 1,
                  },
              },
          )

      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("veo/veo-3.1-fast-generate-001", {
        instances: [
          {
            prompt: "a single red maple leaf falling onto still water, slow motion",
          },
        ],
        parameters: {
          durationSeconds: 4,
          generateAudio: false,
          sampleCount: 1,
        },
      });

      console.log(data);
      ```

      ```bash cURL theme={null}
      curl https://api.comfy.org/v2/models/veo/veo-3.1-fast-generate-001 \
        -H "X-API-Key: $COMFY_API_KEY" \
        -H "Idempotency-Key: $(uuidgen)" \
        -H "Content-Type: application/json" \
        -d "{\"instances\": [{\"prompt\":\"a single red maple leaf falling onto still water, slow motion\"}], \"parameters\": {\"durationSeconds\":4,\"generateAudio\":false,\"sampleCount\":1}}"
      ```
    </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/veo/veo-3.1-fast-generate-001/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(
              "veo/veo-3.1-fast-generate-001",
              {
                  "instances": [
                      {
                          "prompt": "a single red maple leaf falling onto still water, slow motion",
                      },
                  ],
                  "parameters": {
                      "durationSeconds": 4,
                      "generateAudio": False,
                      "sampleCount": 1,
                  },
              },
          )
          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("veo/veo-3.1-fast-generate-001", {
        instances: [
          {
            prompt: "a single red maple leaf falling onto still water, slow motion",
          },
        ],
        parameters: {
          durationSeconds: 4,
          generateAudio: false,
          sampleCount: 1,
        },
      });
      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/veo/veo-3.1-fast-generate-001/requests \
        -H "X-API-Key: $COMFY_API_KEY" \
        -H "Idempotency-Key: $(uuidgen)" \
        -H "Content-Type: application/json" \
        -d "{\"instances\": [{\"prompt\":\"a single red maple leaf falling onto still water, slow motion\"}], \"parameters\": {\"durationSeconds\":4,\"generateAudio\":false,\"sampleCount\":1}}"

      # 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/veo/veo-3.1-fast-generate-001/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/veo/veo-3.1-fast-generate-001/requests/$REQUEST_ID \
        -H "X-API-Key: $COMFY_API_KEY"
      ```
    </CodeGroup>
  </Tab>
</Tabs>

## Schema

### Input

<ParamField body="instances" type="object[]" />

<ParamField body="instances[].cameraControl" type="string">
  Camera motion type. Requires image to be provided.

  Possible values: `fixed`, `pan_left`, `pan_right`, `tilt_up`, `tilt_down`, `truck_left`, `truck_right`, `pedestal_up`, `pedestal_down`, `push_in`, `pull_out`
</ParamField>

<ParamField body="instances[].image" type="object">
  Optional first frame image to guide video generation
</ParamField>

<ParamField body="instances[].image.bytesBase64Encoded" type="string (byte)">
  Base64-encoded image data

  Format: `byte`
</ParamField>

<ParamField body="instances[].image.gcsUri" type="string">
  Cloud Storage URI of the image
</ParamField>

<ParamField body="instances[].image.mimeType" type="string">
  MIME type of the image (image/jpeg or image/png)

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

<ParamField body="instances[].lastFrame" type="object">
  Optional last frame image. Used with image to generate video between first and last frames. Supported by Veo 3.0+ models.
</ParamField>

<ParamField body="instances[].lastFrame.bytesBase64Encoded" type="string (byte)">
  Base64-encoded image data

  Format: `byte`
</ParamField>

<ParamField body="instances[].lastFrame.gcsUri" type="string">
  Cloud Storage URI of the image
</ParamField>

<ParamField body="instances[].lastFrame.mimeType" type="string">
  MIME type of the image (image/jpeg or image/png)

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

<ParamField body="instances[].mask" type="object">
  Optional mask for video editing. Applies to input video.
</ParamField>

<ParamField body="instances[].mask.bytesBase64Encoded" type="string (byte)">
  Base64-encoded mask bytes

  Format: `byte`
</ParamField>

<ParamField body="instances[].mask.gcsUri" type="string">
  Cloud Storage URI to mask file
</ParamField>

<ParamField body="instances[].mask.maskMode" type="string">
  How the mask is applied

  Possible values: `insert`, `remove`, `remove_static`, `outpaint`
</ParamField>

<ParamField body="instances[].mask.mimeType" type="string">
  MIME type of the mask (image/png, image/jpeg, image/webp, or video formats)
</ParamField>

<ParamField body="instances[].prompt" type="string" required>
  Text description of the video to generate
</ParamField>

<ParamField body="instances[].referenceImages" type="object[]">
  Optional reference images to guide video generation. Supports up to 3 asset images or 1 style image. Supported by Veo 3.1 models (preview).
</ParamField>

<ParamField body="instances[].referenceImages[].image" type="object" required />

<ParamField body="instances[].referenceImages[].image.bytesBase64Encoded" type="string (byte)">
  Base64-encoded image data

  Format: `byte`
</ParamField>

<ParamField body="instances[].referenceImages[].image.gcsUri" type="string">
  Cloud Storage URI of the image
</ParamField>

<ParamField body="instances[].referenceImages[].image.mimeType" type="string">
  MIME type of the image (image/jpeg or image/png)

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

<ParamField body="instances[].referenceImages[].referenceId" type="string">
  Optional identifier for the reference image
</ParamField>

<ParamField body="instances[].referenceImages[].referenceType" type="string" required>
  Type of reference image

  Possible values: `asset`, `style`
</ParamField>

<ParamField body="instances[].video" type="object">
  Optional input video for video extension or editing. Incompatible with image and referenceImages.
</ParamField>

<ParamField body="instances[].video.bytesBase64Encoded" type="string (byte)">
  Base64-encoded video bytes

  Format: `byte`
</ParamField>

<ParamField body="instances[].video.gcsUri" type="string">
  Cloud Storage URI of the input video
</ParamField>

<ParamField body="instances[].video.mimeType" type="string">
  MIME type of the video

  Possible values: `video/mov`, `video/mpeg`, `video/mp4`, `video/mpg`, `video/avi`, `video/wmv`, `video/mpegps`, `video/x-flv`
</ParamField>

<ParamField body="parameters" type="object" />

<ParamField body="parameters.aspectRatio" type="string">
  Aspect ratio of the generated video. Default: 16:9

  Possible values: `16:9`, `9:16`
</ParamField>

<ParamField body="parameters.compressionQuality" type="string">
  Video compression quality. Default: optimized

  Possible values: `optimized`, `lossless`
</ParamField>

<ParamField body="parameters.durationSeconds" type="number">
  Target duration of the generated video in seconds. Veo 2: 5-8. Veo 3/3.1: 4, 6, or 8. Default: 8
</ParamField>

<ParamField body="parameters.enhancePrompt" type="boolean">
  Automatically improve prompt for higher quality. Defaults to true.
</ParamField>

<ParamField body="parameters.fps" type="integer">
  Frame rate of generated videos in frames per second
</ParamField>

<ParamField body="parameters.generateAudio" type="boolean">
  Whether to generate audio along with the video. Defaults to true. Supported by Veo 3.0+ models.
</ParamField>

<ParamField body="parameters.negativePrompt" type="string">
  Text describing what to avoid in the generated video
</ParamField>

<ParamField body="parameters.personGeneration" type="string">
  Controls people in generated videos. Default: allow\_adult

  Possible values: `dont_allow`, `allow_adult`, `allowAll`
</ParamField>

<ParamField body="parameters.pubsubTopic" type="string">
  Cloud Pub/Sub topic for progress updates (projects/\{project}/topics/\{topic})
</ParamField>

<ParamField body="parameters.resizeMode" type="string">
  Resize approach for input image. Default: pad

  Possible values: `pad`, `crop`
</ParamField>

<ParamField body="parameters.resolution" type="string">
  Output video resolution. Supported by Veo 3.0+ models. Default: 720p

  Possible values: `720p`, `1080p`, `4k`
</ParamField>

<ParamField body="parameters.sampleCount" type="integer">
  Number of videos to generate. If not specified, 1 video is generated.

  Range: `1` to `4`
</ParamField>

<ParamField body="parameters.seed" type="integer">
  Random seed for deterministic output. Different seeds used per video if sampleCount > 1.

  Format: `uint32`
</ParamField>

<ParamField body="parameters.storageUri" type="string">
  Cloud Storage URI (gs\://) for saving generated videos
</ParamField>

<ParamField body="parameters.task" type="string">
  Operation type for the video generation request

  Possible values: `textToVideo`, `imageToVideo`, `referenceToVideo`, `edit`, `extend`, `upscale`
</ParamField>

Generated from the schema Router serves at `GET /v2/models/veo/veo-3.1-fast-generate-001/openapi.json`, the same document it validates a call against before the request reaches the provider.

### Output

<ResponseField name="done" type="boolean">
  Whether the operation has completed
</ResponseField>

<ResponseField name="error" type="object">
  Error details, present if the operation failed
</ResponseField>

<ResponseField name="error.code" type="integer">
  gRPC error code
</ResponseField>

<ResponseField name="error.message" type="string">
  Error message
</ResponseField>

<ResponseField name="name" type="string">
  Operation resource name
</ResponseField>

<ResponseField name="response" type="object">
  The prediction response, present when done is true
</ResponseField>

<ResponseField name="response.@type" type="string" />

<ResponseField name="response.raiMediaFilteredCount" type="integer">
  Number of videos filtered by responsible AI policies
</ResponseField>

<ResponseField name="response.raiMediaFilteredReasons" type="string[]">
  Reasons why videos were filtered by responsible AI policies
</ResponseField>

<ResponseField name="response.videos" type="object[]" />

<ResponseField name="response.videos[].bytesBase64Encoded" type="string">
  Base64-encoded video content
</ResponseField>

<ResponseField name="response.videos[].gcsUri" type="string">
  Cloud Storage URI of the generated video
</ResponseField>

<ResponseField name="response.videos[].mimeType" type="string">
  Video MIME type (video/mp4)
</ResponseField>

## Examples

### Input

```json theme={null}
{
  "instances": [
    {
      "prompt": "a single red maple leaf falling onto still water, slow motion"
    }
  ],
  "parameters": {
    "durationSeconds": 4,
    "generateAudio": false,
    "sampleCount": 1
  }
}
```

### Output

```json theme={null}
{
  "done": true,
  "name": "projects/example-project/locations/us-central1/publishers/google/models/veo-3.1-fast-generate-001/operations/1a2b3c4d",
  "response": {
    "@type": "type.googleapis.com/cloud.ai.large_models.vision.GenerateVideoResponse",
    "raiMediaFilteredCount": 0,
    "videos": [
      {
        "gcsUri": "https://storage.googleapis.com/EXAMPLE_BUCKET/veo/USER_ID/REQUEST_ID/sample_0.mp4",
        "mimeType": "video/mp4"
      }
    ]
  }
}
```

## 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>