Answer
The Zhongchang shi was the highest position for eunuchs during Cai Lun's time. This position was established in 25 BC by the Han emperor Guangwudi, who was a major patron of eunuchs. The Zhongchang shi was responsible for overseeing the palace eunuchs and was in charge of the palace's finances. The position was often held by powerful eunuchs who could wield great influence over the emperor.