The kobold turned-dragon says "I can't detect any traps... but like I said, it is thrumming with energy. So even if isn't exactly a trap, I don't know if it's going to be healthy to open it. I can conjure a spell to open it from a distance, though... "
He then mutters a few arcane words, mixed with curses in draconic, and moves back to the center of the room. An invisible force then attempts to pull open the white door.
[spoiler]
Xurkwar casts Unseen Servant (using his Uncanny Forethought ability), and has it attempt to open the door, after he's moved back from it.[/spoiler]