The main function was to assist the tasks of the minister and to attend and execute court councils, and the number of regular personnel was originally four, but reduced to two in 705 when Chunagon (vice-councilor of state) was reintroduced.
主な職掌は、大臣の仕事を補佐し朝議に加わりそれを施行することで、定員は始め4人であったが、705年の中納言の復活と共に2人に減らされる。