This item is provided when you start the quest which starts with Baristolth of the Shifting Sands at Cenarion Hold in Silithus.
A character can also receive this item when they are deputized by another character using the.
When you have the Agent in your bag, it allows you to lootfrom the corpses of silithids in Hive'Ashi, Hive'Regal, and Hive'Zora. When you turn 200 Fragments into Baristolth, you earn Brood of Nozdormu reputation.
Patch 1.9.0 (03-Jan-2006): Added