In the oldest surviving manuscript of both works, the 6th- or 7th-century Codex Arcerianus,[4] the name appears as AGGENVS or AGENVS VRBICVS.
Moreover, Karl Lachmann starts from the assumption that Agennius Urbicus based the majority of the text on the work of Frontinus and attempted to reconstruct his second book on land surveying on that basis.
This makes it roughly contemporary with the first compilation and reworking of the Agrimensor texts, which led to the creation of the Corpus Agrimensorum Romanorum.
The commentator declares his goal to be the explanation of older texts that were considered difficult: "We have undertaken to deal with the characteristics of fields and to explain them in plain and simple language, and we hope that what has been composed by the ancients in obscure language may be laid out more openly and comprehensibly for the childlike intellect of modern times.
Attached to the Commentum is a volume with text illustrated with geometric diagrams, known as the Liber diazographus ("Multi-coloured Painter Book"), which is sometimes counted as a separate work.
"[13] However, it is uncertain how far the issues with the works ascribed to Agennius are due to subsequent transmission errors and interpolations.