Frutolf was possibly a teacher of the quadrivium in the monastery, but principally a librarian and manuscript copyist. In this capacity he was responsible for a substantial increase in the stock of the Michelsberg library. Some of the manuscripts he copied are still extant.
He was also an author, writing in Latin. His "Chronicle of the World" (Chronica) is among the most complete and best-organised of the early Middle Ages. It extends from the creation to 1099 and after Frutolf's death was edited and extended by Ekkehard von Aura. It is also fairly certain that a "Breviary of Music" (Breviarium de musica) is by him. On the other hand it is doubtful if he wrote either the "Book of Divine Offices" (Liber de divinis officiis) or the set of instructions to a board game with counters which are sometimes attributed to him.
Schmale, Franz-Josef (ed.), 1972: Frutolfs und Ekkehards Chroniken und die anonyme Kaiserchronik. in I. Schmale-Ott: Ausgewählte Quellen zur deutschen Geschichte des Mittelalters (Freiherr-vom-Stein-Gedächtnisausgabe), vol. 15, 1972; includes inter alia Einführung zu Frutolf, pp. 4–19; Frutolfs Chronik, pp. 46–121 (Latin/German text from the year 1000 onwards)