core/homeassistant/components/transmission/services.yaml

add_torrent:
  description: Add a new torrent to download (URL, magnet link or Base64 encoded).
  fields:
    name:
      description: Instance name as entered during entry config
      example: Transmission
    torrent:
      description: URL, magnet link or Base64 encoded file.
      example: http://releases.ubuntu.com/19.04/ubuntu-19.04-desktop-amd64.iso.torrent

remove_torrent:
  description: Remove a torrent
  fields:
    name:
      description: Instance name as entered during entry config
      example: Transmission
    id:
      description: ID of a torrent
      example: 123
    delete_data:
      description: Delete torrent data
      example: false

start_torrent:
  description: Start a torrent
  fields:
    name:
      description: Instance name as entered during entry config
      example: Transmission
    id:
      description: ID of a torrent
      example: 123

stop_torrent:
  description: Stop a torrent
  fields:
    name:
      description: Instance name as entered during entry config
      example: Transmission
    id:
      description: ID of a torrent
      example: 123