Reading the website and guest directory at any hotel will allow any reasonable guest the easy opportunity to discover what amenities might be on offer. This is true at each individual Luxury Collection hotel—with or without butler service.
For the challenged, it’s also true for the entire St Regis brand on their website for all to see:
Starwood Hotels & Resorts
When in doubt, it’s always possible to ask, too. If you aren’t sure and don’t ask, just as I tell all of my students, you’re responsible for your own ignorance.