OP's opening statement was a little off. What OP went on to describe was not "comprehensive documentation" in the Agile sense but merely "documenting progress

OP's opening statement was a little off. What OP went on to describe was not "comprehensive documentation" in the Agile sense but merely "documenting progress and learnings as to not repeat mistakes". The "comprehensive documentation" in Agile is trying to avoid the "We have delivered exactly what you asked for even it if is no longer what you need."