Video Extension

Extend Kling-generated videos via POST /kling/v1/videos/video-extend using task_id and video_id; run as a sub-task on the parent account.

POST /kling/v1/videos/video-extend

Video Extension

cURL

curl --request POST \
  --url https://api.cometapi.com/kling/v1/videos/video-extend \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "video_id": "example"
}
'

200

{
  "code": 123,
  "message": "<string>",
  "request_id": "<string>",
  "data": {
    "task_id": "<string>",
    "task_status": "<string>",
    "task_status_msg": "<string>",
    "task_info": {
      "parent_video": {
        "id": "<string>",
        "url": "<string>",
        "duration": "<string>"
      }
    },
    "task_result": {
      "videos": [
        {
          "id": "<string>",
          "url": "<string>",
          "duration": "<string>"
        }
      ]
    },
    "created_at": 123,
    "updated_at": 123
  }
}

Use this endpoint to extend an existing Kling video as a follow-up task.

Before you call it

• Start from a finished Kling video result
• Pass the video_id from the parent task result
• Run the extension on the same account context as the parent task
• Trigger the extension promptly before parent-task resources expire

Task flow

1. Finish the parent video task

   Create the original Kling video and wait until its result is available.

2. Submit the extension request

   Send the video_id and optional prompt, then save the returned task id.

3. Poll the extension task

   Continue with Individual Queries until the extended video reaches a terminal state.

For the complete parameter reference, see the official Kling documentation.

Authorizations

Authorization · string · header · required

Bearer token authentication. Use your CometAPI key.

Body

application/json

video_id · string · default: example · required

Video id from a previously generated Kling video task to extend.

prompt · string

Text prompt describing the desired motion for the extended segment. Maximum 500 characters.

callback_url · string

Webhook URL to receive task status updates when the task completes.

Response

200 - application/json

Successful Response

code · integer · required

Error code; specifically define the error code

message · string · required

error message

request_id · string · required

Request ID, system-generated, for tracking requests, troubleshooting issues

data · object · required

Show child attributes