Note that oviraptors do NOT collect the eggs of your (tribe's) tames. Oviraptors are useful because they will collect wild eggs and will allow you to pick them up without aggro-ing any nearby dinos.
To use them, set them to passive and following you/your flyer, drop them near the egg, fly closer to it, then pick your oviraptor up after it snatches the egg. Fly to a safe place (if you're in dangerous territory) to collect the egg!
Everyone needs to know and it is dev confirmed that Oviraptors DO NOT buff chances of mutations or twins or triplets. This is a long going myth that needs to be shut down. Any twins or triplets you are getting is purely coincidence. This was said by one of the devs on twitter!
These guys can steal eggs without aggroing surrounding dinos! You can get easy wyvern and rock drake eggs! Put it in a cryo pod, sneak into a nest, pop it out of the pod and have it set to follow close, run to the other side of the nest and when it gets to the nest it will take the egg. Once it has the egg you can take the egg from it and there won't be any aggro. Just make sure you don't switch the egg out of your inventory because you'll get the aggro then. Rinse and repeat for super easy wyvern and rock drake eggs!