I'm experimenting with building an agent swarm to take a very large existing app that's been built over the past two decades (internal to the company I work for) and reverse engineer documentation from the code so I can then use that documentation as the basis for my teams to refactor big chunks of old-no-longer-owned-by-anyone features and to build new features using AI better. The initial work to just build a large-scale understanding of exactly what we actually run in prod is a massively parallelizable task that should be a good fit for some documentation writing agents. Early days but so far my experiments seem to be working out.

Obviously no users will see a benefit directly but I reckon it'll speed up delivery of code a lot.