- "I am a T-12 service droid, my lord. My primary function is maintenance."
- ―T-12 service droid in Cinnagar
T-12 service droids were employed by the Jedi to assist in cataloging Sith artifacts that were to be shipped to the Great Jedi Library on Ossus after the Freedon Nadd Uprising. They were also used at the Conclave on Deneba in 3997 BBY when the Krath unleashed their programming trap turning the simple serving droids into deadly assassins.
When Nomi Sunrider was captured attempting to rescue Ulic Qel-Droma from Cinnagar after he infiltrated the Krath, Qel-Droma reprogrammed a T-12 droid to take a message to Nomi, advising her to use her Jedi ability to escape and not come back for him. Satal Keto intercepted the droid before it could reach Nomi in the dungeons and after forcing the droid to reveal Qel-Droma's message, Satal ordered one of his shocktroopers to assassinate Qel-Droma.