ha-core/homeassistant/components/facebox/services.yaml

teach_face:
  description: Teach facebox a face using a file.
  fields:
    entity_id:
      description: The facebox entity to teach.
      example: 'image_processing.facebox'
    name:
      description: The name of the face to teach.
      example: 'my_name'
    file_path:
      description: The path to the image file.
      example: '/images/my_image.jpg'