I WONDER - What Is An Oviraptor?

The Oviraptor was a small dinosaur from the Late Cretaceous period, found in Mongolia and China. It measured about 6.5 feet in length and weighed around 50 pounds. With a toothless beak, it likely consumed plants, eggs, and small animals. The name 'Oviraptor' comes from its discovery in the 1920s atop a nest of eggs, leading to the assumption it was an egg thief.

Why was the Oviraptor named as such?

What assumption did paleontologists make about the Oviraptor's behavior?