Just saying

Send a message to a node:

client.justsaying('light/new_address_to_watch', 'BVVJ2K7ENPZZ3VYZFWQWK7ISPCATFIW3');

You need to subscribe to WebSocket notifications see here to see messages sent to you. Here is an example of a notification:

[
  'justsaying',
  {
    subject: 'info',
    body: 'now watching BVVJ2K7ENPZZ3VYZFWQWK7ISPCATFIW3'
  }
]