My players wolf has a bite that includes a trip attack. Does the trip attack cause an attack of opportunity from the target.
Only if the wolf has greater trip, which it does not. Standing up from being tripped, on the other hand, does.
And if you mean "Does the Trip attack provoke an AoO from the target," the answer is still no. This is noted in the Universal Monster Rules, under the Trip ability.
The trip itself does not cause an attack of opportunity, but standing up from being tripped is a move action which does.
Although the target has the option to stand-up as a full round action that does not provoke.
Although the target has the option to stand-up as a full round action that does not provoke.
I have this as a house-rule which I once thought was official, but it has no support in the core book.
So it doesn't. Thanks for the catch there! That's what I get for getting my pathfinder introduction from 3.5 players.