Google Action- help with invocations

Newbie question! I have built Alexa skills for some time, but with Google Actions I am just missing something basic I am sure. When I build a new action in Voiceflow it starts with “Hey Google, talk to…” and then I add my next step, for example, play a mp3 audio file. No problem. But when I go to publish, Google has filled in “Hey Google, start…”, “Hey Google, play…” etc. When I go to publish, it says my skill does not support these, so I have to delete them. My question is, how do I make voiceflow support those additional invocations? I have studies docs and I think I need a visual or example project to connect the dots.