Seedance 2.0 Material Library

Create reusable image, video or audio materials, then use the returned uri in a Seedance video request.

All requests use https://api.uniall.ai and Authorization: Bearer $UNIAI_API_KEY.

1. Create a material

POST /v1/materials requires an Idempotency-Key header and a JSON body:

Parameter	Type	Required	Description
url	string	Yes	Public HTTP(S) media URL, up to 4,096 characters.
type	string	Yes	image, video or audio; must match the media.
name	string	No	Material name, up to 64 characters.

curl "https://api.uniall.ai/v1/materials" \
  -H "Authorization: Bearer $UNIAI_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: product-reference-001" \
  -d '{
    "url": "https://cdn.example.com/product.png",
    "type": "image",
    "name": "Product reference"
  }'

HTTP 202 response:

{
  "id": "mat_EXAMPLE",
  "object": "material",
  "name": "Product reference",
  "type": "image",
  "status": "processing",
  "uri": null,
  "preview_url": null,
  "created_at": "2026-10-29T10:00:00Z",
  "available_at": null,
  "expires_at": null
}

• Use a key of 1–200 visible ASCII characters without spaces. Retrying the same request with the same key returns the same material; changed parameters return HTTP 409 (material_idempotency_conflict). After a timeout, retry with the original key.
• Keep the URL publicly reachable during processing, without login, cookies or custom headers. The current website's Create Material form takes a source URL; this API accepts JSON URLs, not multipart files or Base64. For a local file, first make it available at a public HTTP(S) URL.

Images and videos of people use the same creation request. Follow any additional verification instructions returned by the API.

2. Wait until available

Query the returned id every 3–5 seconds until status is available:

curl "https://api.uniall.ai/v1/materials/mat_EXAMPLE" \
  -H "Authorization: Bearer $UNIAI_API_KEY"

Example response; timestamps are illustrative:

{
  "id": "mat_EXAMPLE",
  "object": "material",
  "name": "Product reference",
  "type": "image",
  "status": "available",
  "uri": "asset://asset-EXAMPLE",
  "preview_url": "https://cdn.example.com/preview.png",
  "created_at": "2026-10-29T10:00:00Z",
  "available_at": "2026-10-29T10:01:00Z",
  "expires_at": "2026-10-30T12:00:00Z"
}

Use the exact uri returned by the API. mat_* is the ID for querying and deleting a material; do not construct an asset:// URI from it. The expiry time is expires_at; use the material before that time.

Status	Action
creating, processing	Continue querying.
available	The returned uri is ready to use.
failed	Read error.code and error.message. To create a new material, use a new idempotency key.
delete_pending, deleted	Stop using the material.

3. Generate a video with the URI

Replace asset://asset-EXAMPLE below with the uri from your available image material:

curl "https://api.uniall.ai/v1/videos" \
  -H "Authorization: Bearer $UNIAI_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "seedance2.0-fast",
    "resolution": "480p",
    "duration": 4,
    "aspect_ratio": "16:9",
    "generate_audio": false,
    "content": [
      {
        "type": "text",
        "text": "Keep the product appearance consistent as the camera slowly moves around it."
      },
      {
        "type": "image_url",
        "image_url": {"url": "asset://asset-EXAMPLE"},
        "role": "reference_image"
      }
    ]
  }'

Put the URI in a structured media field such as image_url.url, not in the prompt. For video or audio materials, use the matching video_url or audio_url field. Use materials owned by the same UniAI user and still available and unexpired.

Use the returned video task ID to query the video and retrieve its result.

List materials

curl "https://api.uniall.ai/v1/materials?type=image&status=available&limit=20" \
  -H "Authorization: Bearer $UNIAI_API_KEY"

The response contains data, has_more and next_cursor. Filters: type, status; limit is 1–100, default 50. Pass a returned next_cursor unchanged as after for the next page. Expired and deleted materials are not listed.

Delete a material

curl -X DELETE "https://api.uniall.ai/v1/materials/mat_EXAMPLE" \
  -H "Authorization: Bearer $UNIAI_API_KEY"

HTTP 200 with status: "deleted" means deletion is complete; HTTP 202 with status: "delete_pending" means it is still processing. Repeating DELETE is safe. A completed deletion removes the material from the list, and its detail endpoint returns 404 material_not_found.

Request errors

Error code	What to check
invalid_idempotency_key	Include a valid Idempotency-Key when creating a material.
invalid_material_request	Check the URL, media type and name length.
material_idempotency_conflict	Reuse the original request with that key, or use a new key for a different material.
material_not_found	Check the ID and current user; the material may be deleted or expired.
material_not_available	Wait for available and check expires_at.
material_not_managed	Copy the returned uri from your material instead of constructing one.

See the Seedance 2.0 Series Guide for generation parameters.