He gives the woman a slightly confused look before he senses what's stopping her. It's... designed to let only mages through? That's fascinating, and at any other time he'd want to have time to study it but the party needs to pass.

"I can dispel it," Anders says, pulling the staff off his back slowly as he does as much sensing of the thing he can. It's not enough to truly figure the spell out, but at least he has a vague shape to go off of by the time he's casting and removing the barrier.

"There we go. You can pass now."