For example, according to "Kaitoshokokuki" (literally, descriptions of various countries across the sea) written by Sukchu SIN, a secretary of the envoy dispatched in 1428, the survey included 15 items including the following: identifying base-places of wako together with a request of prohibiting wako (Japanese pirates) actions, observing Japan's power, such as relationships among wako, shugo daimyo (shugo, which were Japanese provincial military governors, that became daimyo, which were Japanese feudal lords), dominant Kokujin (local samurai) and local clans, states of progress in urban areas, and monetary policies, and checking the states of progress of Buddhism in Japan.
例えば1428年（正長元年）派遣の使節に同行した書記官の申叔舟が著した『海東諸国紀』によると、倭寇禁圧要請と併せて倭寇の根拠地の特定、倭寇と守護大名、有力国人、土豪との関係、都市部の発展状況や通貨政策など国力状況の観察、日本での仏教の展開状況をはじめ15項目の調査内容があったという。