Luke repeatedly tells people his boat is a ship and not a boat but by all common definitions (size, location of control, turning profile and area of use) it is a boat. However, this is not a goof, it is a joke at the expense of the character, to add softening comedic effect to the drama.
In order to avoid huge wrongful death lawsuits which would expose the Agency to discovery and trial, CIA operatives are obligated to disclose their affiliation to their married spouses. It would not be a surprise to Luke's ex-wife where he is all the time.