There isn't an option to automate the guiding assistant. I'm not sure how you would do it (or if you would really want to do that). Having personally used NINA advanced sequencer and PHD for some years, I think the basic operating assumption is your guiding is basically working and set up correctly. You can recalibrate as an option, and with the PHD2 Tools plugin you can also do things like change exposure time, shut down PHD, etc.. What features are available there is really within the plugin.
Brian