# Seedance 2.5 — API Reference

Model ID: `model_bytedance-seedance-2-5`

---

## Authentication

- **API_KEY** and **API_SECRET** are found in your [Scenario Project Settings](https://app.scenario.com/team&tab=api_keys) under API Keys.
- Set them as environment variables `SCENARIO_SDK_API_KEY` and `SCENARIO_SDK_API_SECRET` — both SDKs pick them up by default.
- For raw HTTP (cURL), use Basic Auth: `Authorization: Basic base64("<API_KEY>:<API_SECRET>")`.

### Install the SDK

- JavaScript / TypeScript: `npm install @scenario-labs/sdk`
- Python: `pip install scenario-sdk`

---

## Generate

**Endpoint:** `POST https://api.cloud.scenario.com/v1/generate/custom/model_bytedance-seedance-2-5`

### Parameters

| Parameter | Type | Required | Default | Description |
|-----------|------|----------|---------|-------------|
| `prompt` | string | - | - | Describe the video you want. Use "@" such as "@image1" or "@video1" to reference uploads. Mode is inferred from your inputs and prompt: text-to-video, first/last frame, reference-to-video, editing, or extension. Optional if you provide a first frame or reference images/videos/audio. |
| `image` | assetId | - | - | First frame for image-to-video. Mutually exclusive with reference images/videos. In first/last-frame mode, aspect ratio is ignored (always adaptive to this frame). |
| `lastFrameImage` | assetId | - | - | Optional last frame. Only valid when a first frame is provided. |
| `referenceImages` | assetId[] | - | - | Reference images for multimodal / reference-to-video mode (up to 30). Mutually exclusive with first frame. |
| `referenceVideos` | assetId[] | - | - | Reference videos for multimodal, editing, or extension mode (up to 10). Mutually exclusive with first frame. Editing and extension are inferred from your prompt. |
| `referenceAudio` | assetId[] | - | - | Reference audio tracks (up to 10). Can be used alone, or with reference images/videos. |
| `duration` | number | - | `-1` | How long the video lasts, in seconds (4-30), or Auto. With reference videos, Auto matches the longest reference clip (kept within 4-30s). Ignored in editing mode (must be Auto / -1; output follows the input video). |
| `resolution` | string | - | `720p` | The output quality. Higher resolution is sharper but costs more. |
| `aspectRatio` | string | - | `adaptive` | The shape of the video. Auto picks a fitting shape based on your inputs. Ignored in first/last-frame mode, editing mode, and extension mode (always adaptive to the input). |
| `generateAudio` | boolean | - | `true` | Adds a generated soundtrack to the video. |
| `outputFormat` | string | - | `mp4` | Video container format. MP4 is the general-purpose delivery format; MOV keeps higher colour fidelity for grading and compositing (larger files, narrower player support). |

### Example Requests

**cURL**

```bash
curl -X POST "https://api.cloud.scenario.com/v1/generate/custom/model_bytedance-seedance-2-5" \
  -H "Authorization: Basic $(echo -n '<API_KEY>:<API_SECRET>' | base64)" \
  -H "Content-Type: application/json" \
  --data-binary @- <<'EOF'
{
  "duration": -1,
  "resolution": "720p",
  "aspectRatio": "adaptive",
  "generateAudio": true,
  "outputFormat": "mp4"
}
EOF
```

**Python**

```python
import os
from scenario_sdk import Scenario

client = Scenario(
    api_key=os.environ.get("SCENARIO_SDK_API_KEY"),
    api_secret=os.environ.get("SCENARIO_SDK_API_SECRET"),
)

body = {
    "duration": -1,
    "resolution": "720p",
    "aspectRatio": "adaptive",
    "generateAudio": True,
    "outputFormat": "mp4"
}

response = client.generate.run_model(
    model_id="model_bytedance-seedance-2-5",
    body=body,
)
print(response)
```

**JavaScript**

```javascript
import Scenario from "@scenario-labs/sdk";

const client = new Scenario({
  apiKey: process.env["SCENARIO_SDK_API_KEY"],
  apiSecret: process.env["SCENARIO_SDK_API_SECRET"],
});

const body = {
  "duration": -1,
  "resolution": "720p",
  "aspectRatio": "adaptive",
  "generateAudio": true,
  "outputFormat": "mp4"
};

const response = await client.generate.runModel("model_bytedance-seedance-2-5", { body });
console.info(response);
```

---

## Retrieve Results

After submitting a generation request, you receive a `jobId`. Poll the job until `job.status` is `"success"`. The generated asset IDs are in `job.metadata.assetIds`.

**Endpoint:** `GET https://api.cloud.scenario.com/v1/jobs/{jobId}`

### Example Requests

**cURL**

```bash
curl -X GET "https://api.cloud.scenario.com/v1/jobs/<JOB_ID>" \
  -H "Authorization: Basic $(echo -n '<API_KEY>:<API_SECRET>' | base64)"
```

**Python**

```python
job = client.jobs.retrieve(job_id="<JOB_ID>")
print(job.status)
print(job.metadata.asset_ids)
```

**JavaScript**

```javascript
// Option 1 — wait on the response from runModel using the SDK helper
const completed = await response.job.wait();
console.info(completed.status);
console.info(completed.metadata?.assetIds);

// Option 2 — retrieve a job by its ID
const job = await client.jobs.retrieve("<JOB_ID>");
console.info(job.status);
console.info(job.metadata?.assetIds);
```

**Example response:**

```json
{
  "job": {
    "jobId": "job_abc123",
    "status": "success",
    "metadata": {
      "assetIds": [
        "asset_abc123"
      ]
    }
  }
}
```

> **Important:** Generated asset URLs are **temporary** and expire after a short period. Download and store any images you wish to keep before the URL expires. More info: [Content Delivery Network (CDN)](https://docs.scenario.com/get-started/documentation/content-delivery-network-cdn).

---

*Generated by [Scenario](https://app.scenario.com)*