type: object
properties:
  content:
    type: string
    description: The content of the message
    required: true
  message_type:
    type: string
    enum: ['outgoing', 'incoming']
  private:
    type: boolean
    description: Flag to identify if it is a private note
  content_type:
    type: string
    enum: ['input_select', 'form', 'cards']
  content_attributes:
    type: object
    description: options/form object