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

# Kling 2.1

> Standard and Pro image-to-video generation

<Tip>
  1. After submission, a `task_id` will be returned. If you provided a `callback_url`, when the task status becomes `finished` or `failed`, a POST request will be sent to the `callback_url`.
  2. Regardless of whether `callback_url` is provided, you can retrieve the result through the unified [Query Task Status](/api-manual/task-management/status) endpoint.
</Tip>

# Kling 2.1

Kling 2.1 provides two public models under the same request format: `kling-2.1/standard` and `kling-2.1/pro`.

## Available Models

* **kling-2.1/standard** - Start-frame guided image-to-video
* **kling-2.1/pro** - Start-frame guided image-to-video with optional end frame

## Required Parameters

* **prompt**: Text prompt for generation
* **start\_image\_url**: Required first frame image

## Optional Parameters

* **duration**: `5` or `10`. Default is `5`
* **end\_image\_url**: Optional, only supported by `kling-2.1/pro`
* **negative\_prompt**: Optional negative prompt

## Notes

* `kling-2.1/standard` does not support `end_image_url`
* `kling-2.1/pro` supports both start image and optional end image


## OpenAPI

````yaml /api-manual/video-series/kling-2-1.json POST /api/generate/submit
openapi: 3.0.0
info:
  title: Vidgo API - Kling 2.1 API
  description: Standard and Pro image-to-video generation
  version: 1.0.0
servers:
  - url: https://api.vidgo.ai
    description: Production server
security:
  - BearerAuth: []
paths:
  /api/generate/submit:
    post:
      tags:
        - Kling 2.1
      summary: Submit Kling 2.1 Task
      description: Generate video with Kling 2.1 Standard or Pro
      operationId: submitKling21Task
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/SubmitRequest'
            examples:
              kling-2-1-standard:
                summary: Kling 2.1 Standard
                value:
                  model: kling-2.1/standard
                  callback_url: https://your-domain.com/callback
                  input:
                    prompt: >-
                      a woman takes her hands out her pockets and gestures to
                      the words with both hands, she is excited, behind her it
                      is raining
                    duration: 5
                    start_image_url: >-
                      https://cdn.doculator.org/kling-2.1/start-image.png?v=20260310-2040
              kling-2-1-pro:
                summary: Kling 2.1 Pro
                value:
                  model: kling-2.1/pro
                  callback_url: https://your-domain.com/callback
                  input:
                    prompt: >-
                      a woman takes her hands out her pockets and gestures to
                      the words with both hands, she is excited, behind her it
                      is raining
                    duration: 5
                    start_image_url: >-
                      https://cdn.doculator.org/kling-2.1/start-image.png?v=20260310-2040
      responses:
        '200':
          description: Task submitted successfully
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/SubmitResponse'
components:
  schemas:
    SubmitRequest:
      type: object
      required:
        - model
        - input
      properties:
        model:
          type: string
          description: Kling 2.1 public model identifier
          enum:
            - kling-2.1/standard
            - kling-2.1/pro
        callback_url:
          type: string
          format: uri
          description: Webhook callback URL for result notifications
          example: https://your-domain.com/callback
        input:
          type: object
          required:
            - prompt
            - start_image_url
          properties:
            prompt:
              type: string
              description: Text prompt for generation
              example: >-
                a woman takes her hands out her pockets and gestures to the
                words with both hands, she is excited, behind her it is raining
            duration:
              type: integer
              description: Output duration in seconds
              enum:
                - 5
                - 10
              default: 5
              example: 5
            start_image_url:
              type: string
              format: uri
              description: Required first frame image URL
              example: >-
                https://cdn.doculator.org/kling-2.1/start-image.png?v=20260310-2040
            end_image_url:
              type: string
              format: uri
              description: Optional last frame image URL. Only supported by kling-2.1/pro
              example: https://example.com/end-image.png
            negative_prompt:
              type: string
              description: Optional negative prompt
              example: low quality, blur
    SubmitResponse:
      type: object
      required:
        - code
        - data
      properties:
        code:
          type: integer
          example: 200
        data:
          type: object
          required:
            - task_id
            - status
            - created_time
          properties:
            task_id:
              type: string
              example: task-unified-1757165031-uyujaw3d
            status:
              type: string
              enum:
                - not_started
              example: not_started
            created_time:
              type: string
              format: date-time
              example: '2025-11-12T10:30:00'
  securitySchemes:
    BearerAuth:
      type: http
      scheme: bearer
      bearerFormat: API Key
      description: >-
        All API endpoints require Bearer Token authentication


        Get your API Key:


        Visit the [API Key Management
        Page](https://vidgo.ai/apis/dashboard/api-key) to get your API Key


        Add it to the request header:


        ```

        Authorization: Bearer YOUR_API_KEY

        ```

````