Runway Text to Video API

openapi: 3.1.0
info:
  title: Runway Characters Avatars Text to Video API
  description: The Runway Characters API enables developers to build real-time conversational avatars powered by GWM-1, Runway's General World Model. Characters are fully custom conversational video agents that can be created from a single image with no fine-tuning required, supporting photorealistic or animated styles, human or non-human appearances. The API manages avatars, real-time sessions via WebRTC, and knowledge documents that avatars can reference during conversations. Sessions have a maximum duration of 5 minutes.
  version: '2024-11-06'
  contact:
    name: Runway Support
    url: https://support.runwayml.com/
  termsOfService: https://runwayml.com/terms-of-use
servers:
- url: https://api.dev.runwayml.com/v1
  description: Production Server
security:
- bearerAuth: []
tags:
- name: Text to Video
  description: Generate videos from text prompts alone using Gen-4.5, Veo 3.1, or Veo 3.1 Fast models.
paths:
  /text_to_video:
    post:
      operationId: createTextToVideo
      summary: Create text-to-video generation task
      description: Starts a new asynchronous task to generate a video from a text prompt alone, without requiring an input image. Supported by Gen-4.5, Veo 3.1, and Veo 3.1 Fast models. Returns a task ID that can be polled for completion.
      tags:
      - Text to Video
      parameters:
      - $ref: '#/components/parameters/RunwayVersion'
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/TextToVideoRequest'
      responses:
        '200':
          description: Task created successfully
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/TaskCreatedResponse'
        '400':
          description: Bad request - invalid parameters
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
        '401':
          description: Unauthorized - invalid or missing API key
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
        '429':
          description: Rate limit exceeded
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
components:
  parameters:
    RunwayVersion:
      name: X-Runway-Version
      in: header
      required: true
      description: API version identifier. Must be set to the exact value 2024-11-06.
      schema:
        type: string
        enum:
        - '2024-11-06'
  schemas:
    TaskCreatedResponse:
      type: object
      properties:
        id:
          type: string
          format: uuid
          description: The unique identifier for the created task. Use this ID to poll the task status endpoint.
    ErrorResponse:
      type: object
      properties:
        error:
          type: string
          description: A human-readable error message describing what went wrong.
        code:
          type: string
          description: A machine-readable error code identifying the type of error.
    TextToVideoRequest:
      type: object
      required:
      - model
      - promptText
      properties:
        model:
          type: string
          description: The model to use for text-to-video generation. Gen-4.5 supports text-only generation by omitting the promptImage parameter. Veo models also support text-to-video.
          enum:
          - gen4.5
          - veo3.1
          - veo3.1_fast
          - veo3
        promptText:
          type: string
          description: A text description of up to 1000 characters that describes in detail what should appear in the generated output video.
          maxLength: 1000
        duration:
          type: integer
          description: The duration of the generated video in seconds.
          enum:
          - 5
          - 10
        ratio:
          type: string
          description: The aspect ratio of the output video.
          enum:
          - 1280:720
          - 1584:672
          - 1104:832
          - 720:1280
          - 832:1104
          - 960:960
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer
      description: API key passed via the HTTP Authorization header using the Bearer scheme. Obtain your API key from the Runway Developer Portal at https://dev.runwayml.com/.
externalDocs:
  description: Runway Characters Documentation
  url: https://docs.dev.runwayml.com/characters/