The term Kanmon means written reports (Kanshin) for various information such as origins/precedents that were submitted by scholars, etc. at the request of the Imperial court.
勘文（かんもん）とは、朝廷から諮問を依頼された学者などが由来・先例等の必要な情報を調査して報告（勘申）を行った文章のこと。