The quartermaster provided clothing, food, and equipment for the soldiers. Geralt would often find him standing beside an anvil and a grindstone, showing that he was working on the sharpening the soldiers' weapons as he was a blacksmith.
When Geralt first talked to him, he accused him of spying, showing that he did not trust Nordlings. He did so again if Geralt asked about camp morale, and added that the Nilfgaardian victory was assured and nothing more. However, this may only have been a warning since he was keen to trade and do blacksmith work.
† He will only sell these after the prologue is finished and Geralt returns to the area.