I think they are what I have too. They should end up in your live rock and in your sand. Once they have populated these other areas of your tank, I'd break off the ones near your hammers. You won't need them there and I would even go as far as removing them gently and dropping them in your sand to hopefully live there and not amongst your corals. They are as good as bristle worms in scavenging leftovers. You will occasionally see one detach itself and go flying about the tank to find a new place to settle.
If they are what I think they are, they are not spaghetti worms. However, they are still beneficial as every one says above. They do not leave mucus trails.
HOWEVER! If you see an actual head, like a slug head pop out with two antennas, then they could be another type of worm (which I also have), which are not good. These are the ones that do leave send out mucus trails that annoy corals. However, my ones that do this have more of an orange coloured head to them. If you do have these, kill them! They have benefits, but their disadvantages out weigh their benefits Imo. smash their shells and let your wrasse (if you have any) eat them. They will spread if you don't hit them hard! Also, mine tend to form new ones around my hammers.
The bad ones, i.e. the ones that produce the mucous trails tend to have spiral shells. The shells tend to be orange in colour. They are not the tiny little white spirals your might get with the little red feather duster that comes out (those are OK).