send_message:
  description: Send message to target room(s)
  fields:
    message:
      description: The message to be sent.
      example: This is a message I am sending to matrix
    target:
      description: A list of room(s) to send the message to.
      example: "#hasstest:matrix.org"
    data:
      description: Extended information of notification. Supports list of images. Optional.
      example: "{'images': ['/tmp/test.jpg']}"