Captions Meta Text Overlays API

openapi: 3.0.3
info:
  title: Captions AI Creator & AI Ads Meta Text Overlays API
  description: 'REST API for generating AI talking-head videos using community avatars (AI Creator) and UGC-style AI advertising videos (AI Ads). Both APIs are asynchronous: submit a job, then poll for completion. Scripts are limited to 800 characters, supporting 30+ languages with automatic detection. Usage is billed at 1 credit per second of generated video. Rate limit is 5 requests per minute per endpoint.

    '
  version: '1.0'
  contact:
    name: Captions API Support
    url: https://captions.ai/help/docs/api/overview
servers:
- url: https://api.captions.ai/api
  description: Captions API production server
security:
- ApiKeyAuth: []
tags:
- name: Meta Text Overlays
  description: Render static text overlays onto videos
paths:
  /v1/meta/text_overlays:
    post:
      tags:
      - Meta Text Overlays
      summary: Create Meta Text Overlay
      description: 'Render static text overlays onto an uploaded video. Upload once and render up to 4 related text variants against the same input video.

        '
      operationId: createMetaTextOverlay
      parameters:
      - $ref: '#/components/parameters/XApiKey'
      requestBody:
        required: true
        content:
          multipart/form-data:
            schema:
              $ref: '#/components/schemas/CreateMetaTextOverlayRequest'
      responses:
        '200':
          description: Returns a MetaTextOverlay job object
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/MetaTextOverlay'
              example:
                id: d7f76ec6-2500-4d23-a2bc-648f4e904555
                object: text_overlay
                status: QUEUED
                created_at: 1730822400
                results: []
        '422':
          $ref: '#/components/responses/ValidationError'
  /v1/meta/text_overlays/{text_overlay_id}:
    get:
      tags:
      - Meta Text Overlays
      summary: Retrieve Meta Text Overlay
      operationId: getMetaTextOverlay
      parameters:
      - $ref: '#/components/parameters/XApiKey'
      - name: text_overlay_id
        in: path
        required: true
        schema:
          type: string
      responses:
        '200':
          description: Returns the MetaTextOverlay job object
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/MetaTextOverlay'
        '422':
          $ref: '#/components/responses/ValidationError'
components:
  schemas:
    MetaTextOverlayResult:
      type: object
      required:
      - index
      - text
      - status
      description: Per-text result for a Meta text overlay job.
      properties:
        index:
          type: integer
          description: Zero-based index matching the input texts order
        text:
          type: string
          description: Input text for this rendered output
        status:
          type: string
          enum:
          - COMPLETE
          - FAILED
          description: Terminal status for this item
        video_url:
          type: string
          nullable: true
          description: Resolved output video URL when this item completed successfully
        error:
          nullable: true
          allOf:
          - $ref: '#/components/schemas/MAVideoError'
          description: Error details when this item failed
    ValidationError:
      type: object
      required:
      - loc
      - msg
      - type
      properties:
        loc:
          type: array
          items:
            oneOf:
            - type: string
            - type: integer
        msg:
          type: string
        type:
          type: string
    MetaTextOverlay:
      type: object
      required:
      - id
      - status
      - created_at
      description: Represents a Meta text overlay job.
      properties:
        id:
          type: string
          description: Text overlay job ID
        object:
          type: string
          enum:
          - text_overlay
          default: text_overlay
        status:
          type: string
          enum:
          - QUEUED
          - PROCESSING
          - COMPLETE
          - FAILED
          - CANCELLED
          description: Current state of the text overlay job
        created_at:
          type: integer
          description: When the job was created (unix timestamp)
        completed_at:
          type: integer
          nullable: true
          description: When processing reached a terminal state (unix timestamp)
        results:
          type: array
          items:
            $ref: '#/components/schemas/MetaTextOverlayResult'
          description: Ordered per-text render results for this job
        error:
          nullable: true
          allOf:
          - $ref: '#/components/schemas/MAVideoError'
          description: Error details if the job failed before itemized completion
    HTTPValidationError:
      type: object
      properties:
        detail:
          type: array
          items:
            $ref: '#/components/schemas/ValidationError'
    CreateMetaTextOverlayRequest:
      type: object
      required:
      - video
      description: 'Request body for creating a Meta text overlay job. Upload once and render up to 4 related text variants.

        '
      properties:
        video:
          type: string
          format: binary
          description: Source video file (MP4 or MOV).
        texts:
          type: array
          nullable: true
          items:
            type: string
          description: Ordered text variants to render as static overlays (max 4).
        items:
          type: string
          nullable: true
          description: 'Optional JSON array of item objects. Each item must contain text and may contain style.font, style.size, and style.color.

            '
        fonts:
          type: array
          nullable: true
          items:
            type: string
          description: Optional ordered font overrides aligned by index with texts.
        sizes:
          type: array
          nullable: true
          items:
            type: string
          description: Optional ordered font size overrides in pixels aligned by index with texts.
        colors:
          type: array
          nullable: true
          items:
            type: string
          description: Optional ordered text color overrides (#RRGGBB) aligned by index with texts.
    MAVideoError:
      type: object
      required:
      - code
      - message
      description: Error payload that explains why generation failed, if applicable
      properties:
        code:
          type: string
          description: Error code
          example: rate_limit_exceeded
        message:
          type: string
          description: Error message
          example: Rate limit exceeded. Please try again later.
  responses:
    ValidationError:
      description: Validation Error
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/HTTPValidationError'
  parameters:
    XApiKey:
      name: x-api-key
      in: header
      required: true
      description: API Key for authentication
      schema:
        type: string
  securitySchemes:
    ApiKeyAuth:
      type: apiKey
      in: header
      name: x-api-key