His trading activities were reported to Kofuku-ji Temple after their return and put on record in detail in such documents as "Daijoin jisha zojiki (Miscellaneous Records of the Daijo Temple and Shrine)" and the "Tosen Nikki" (lit. "Tosen Journal") by Jinson of Daijo-in, which serve as valuable historical data to describe the actual activities of trading between two countries in those days.
これらの西忍の交易活動は、帰国後興福寺に報告され、大乗院主尋尊によって「大乗院寺社雑事記」「唐船日記」などに詳細に記されており、当時の日明勘合貿易の実際を知る上での貴重な史料となっている。