The Hardex were a species of sentient beings native to the Hardex system, which is located in the Jubilar sector of the Outer Rim Territories. Around 5.5 BBY, the Hardex dispatched an ambassador to Craw, the Targonnian leader. Craw then told a joke involving a bantha and three Hardex to the visiting ambassador. The leader's protocol droid then translated the joke; however, the ambassador did not find it funny. As a result, Craw had the protocol droid deactivated and turned into a water fountain. Later, in 5.5 BBY, the Targonnian captain named Steggus brought up the joke and the ambassador's reaction to it to Craw.
The Hardex were first referenced in Star Wars: Droids, specifically in the sixth issue of this comic-book series. Dark Horse Comics published this issue on October 31, 1995, and it was authored by Jan Strnad.