To monitor what events from devices or time are flying around and what the engine is doing with it, the engine can log its activities with messages. In your Homylon scene you can define a monitor with its whereabouts (IP address, port and protocol) and also what you want to see. If you are testing a home written app or trying to find a something going wrong "ALL" or "JSON" is a good option. Usually you want to see "EVENT" "LOG" "WARNING" "ERROR" and "ENGINE". You can have a number of different monitors displaying different sub sets of messages.
Below are some example monitor apps. A simple one in Python you can run in a terminal and a MacOS/IOS/TVOS app with its sources to run on Apple hardware. These sources are free to use as opensource (MIT licence) so they are a great starting point for your own agents and tools.
Simple Python Monitor Mac app Sources (iPhone/iPad, Mac, Apple TV)