You might want to check out the food pics threads to see entrees others have posted. Its unlikely the plate will be bare besides your actual main cut of meat (or whatever) - likely some vegetables and maybe a starch. In any case, likely much smaller than would be sold as a "side".
(Edit: based on a quick check of Boathouse, looks to be very minimal extra on the plate - small amount of veggies, usually listed in the entree description, plus a sauce.)