Below is the text you can read from within the message.
Your mission is to contact our agent inside Menaphos. Use the tunnels beneath the temple of lesser gods. Be vigilant of traps and the hostile natives. They're about as welcoming as the Menaphites only slightly better looking.
After completion of the associated quest, if you have unlocked the entire Hub track, this item can be retrieved from the Quest Item Storage chest at the Quest Point Caravan if lost or destroyed. Otherwise, a new one cannot be obtained.
There is no need to keep this item after the quest has been completed. As such, it can be destroyed or kept as you desire.