The carpenter is an NPC in Sophanem involved in the Icthlarin's Little Helper quest. He offers to buy willow logs for 40 coins each, though he stops doing this after the completion of Contact!.
If the potion is used on the Carpenter (to relieve him of the itching), he will unfortunately get some of the potion in his eye. Futhermore, the potion has no effect and the Carpenter furiously sends the player away. He is seen in a cutscene in Contact! as part of the High Priest's delegation.
The High Priest leads a delegation of Sophanites to parlay with Menaphos.