type: object
description: |
  Image-to-text request - describe an image using a vision model.

  The image payload is base64-encoded; raw binary is not accepted.
required:
  - image
  - mime_type
properties:
  image:
    type: string
    description: Base64-encoded image payload
    example: iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAADUlEQVR42mNk+M9QDwADhgGAWjR9awAAAABJRU5ErkJggg==
  mime_type:
    type: string
    description: MIME type of the image
    example: image/png
  prompt:
    type: string
    description: |
      Instruction for the vision model. Optional; the service applies a
      default prompt ("Describe this image") when omitted or empty.
    example: List the objects visible in this image.
  system:
    type: string
    description: Optional system prompt that sets behavior and context for the vision model
    example: You are an expert at describing photographs for visually impaired users.