This is from HappyAssassin's WW/trapper guide:
Claws: This is a claw assassin, and your choice of claw is very important. Chaos is a must obviously. It should be your offhand claw. Your Chaos should have +Venom, +Lightning Sentry and +DF on it. For your primary claw, there are really two options. A Fury claw with +Venom and +Lightning Sentry is a very strong option. If you really need the last skill point, look for one with Wake of Fire or Shadow Master. Also, try to get a Fool’s Claw with 40% IAS and good +skills as well. There are really two sets of mods to look for on a Fool’s claw. If you intend to use the Fools only as a switch item to get high AR against heavy melee, then look for one with IAS, high % ED, and 2 Sockets. Another option is to use the Fool’s claw as your primary claw all the time, and switch to Fury only for highly defensive opponents. In this case, look for a Fools with good +skills first and foremost, then IAS, then ED, then sockets, etc. Ideally, you should use a claw that gives +4 or more to your Lightning Sentry, as this will give you powerful traps. I use a Fool’s claw about 90% of the time on my Assassin. Try to get all these claws in Runic Talon. After that, the best options in order are Feral Claws.
It depend's a little.