In what capacity did Peter and Kit accompany tom Boyd to Cumberland?

Basically Peter and Kit accompanied Tom Boyd to Cumberland as guides. Sir Robert had decided to send one of his best agents, Boyd, to Cumberland. Unfortunately Boyed did not know the country and, with his accent, "be as noticeable as a Negro." Peter knew "all the hills and dales" well. Although Kit was not really welcome on the trip, except by Peter, she ended up going just the same.