Direction is sort of arbitrary concept without a relation. Direction of U means nothing unless you ask for the driection in relation to something.
So the question might be dorection comared to origin, in local space in relation to something on a point. Direction itself without theese contraints doesnt mean anything. It cant be clockwise or counterclockwise except if the curve is flat and so on. So it really really depends on what the relation o direction your after, seriously.