Led by Zusho no kami (Director of the Bureau of Drawings and Books), it edited and controlled Kotofu (the genealogy of the Imperial Family) or fact records and so on, and administered the authentic texts of Imperial family-related laws such as Imperial House Act and so on, or precious books kept in Imperial Court.
図書頭を長として皇統譜や実録などの編纂及び管理、皇室典範などの皇室関連法令の正本や貴重な宮中保管書籍の管理などを行った。