As a household superintendent, Nobunori served FUJIWARA no Tadamichi and FUJIWARA no Motozane of the Sekkan (Regent and Chancellor) family, getting information about the movement of high court nobles, especially Goshirakawa in and the Taira family before and after the Hogen Disturbance, so no record can compete with Nobunori's detailed record about them.
特に信範は摂関家の藤原忠通・藤原基実らに家司として仕えたため、当時の上級公家などの動きに詳しく、中でも保元の乱および乱後の後白河院・平家などについての詳細な記述は、他の諸記録の追随を許さないといえる。