By far one of the most annoying aspects of Google Now and Assistant is that you have to speak “OK Google,” before every command. Even though Now and Assistant can continue conversations based on context (for example, you can follow up “Who is the president?” with “How old is he?”), you still have to say “OK Google” before asking anything.
Google Assistant on Android TV, which is coming to all set-top boxes and televisions running Android TV 6.0 Marshmallow or higher, will support continuous conversation mode.
Google Assistant on Android TV supports continuous conversation mode was written by the awesome team at Android Police.