The Republic of Ireland international, 24, has started the last two matches after a three-week absence through injury over the festive period.
"Obviously Seamus offers one or two different things when he plays right-back. We're glad to get him back," said Moyes.
"He's a very good player and he is improving. He is a young boy as far as football goes because he is pretty new into the professional scene.
"He learnt a little bit of his trade as a wide attacking player, albeit he has always been a full-back.
"He provided one or two opportunities for us [against Swansea] and maybe we should have attacked them a bit more."