Populating Autocomplete phrase list using .NET API

I couldn't find anything about this. I have around 2k of page names I'd like to input into the autocomplete phrases list. Those pages come and go as they're synced with an external product DB.

Is there any way I can access said list in the .NET API? Should I just implement my own autocomplete and disregard that functionality entirely? 
Or maybe I'm going the wrong way here?