Recorded deed will more or less universally contain a legal description of the land. This does, in fact, defined the illegal outline of the parcel.

A survey is little more than marching out into the field and putting at the location where you believe the boundaries to be based on your review of the legal description.

Of course that’s not the end of the discussion as to boundaries for reasons like adverse possession or busted titles but on his own a surveyor is going to tell you basically nothing.