Each source in the media database contains useful icons that will help you determine the status of the stream and what devices it may be compatible with. For example, here's a screenshot from the media database:
Icon legend:
Source is online (working)
Source is geo-locked (online, but not accessible by every country)
Source is offline (not working)
Source is compatible with Roku
Source is compatible with Fire TV
Source is compatible with Plex
Source is compatible with Kodi
These icons are also available in your library for sources that you've added from the media database.
Keep in mind, these icons are kept up to date by automated backend systems and may not always be 100% accurate, however they are usually reliable