> I can’t imagine agents wouldn’t perform better in a clean codebase than a giant mess of one.

I guess it depends on what you mean with "better" but almost all the agent-built projects I do with zero regards to code quality, design and architecture ends up with every single agent needing 10+ minutes to do even the easy changes, while the ones where I focused on those things together with the agent, large changes can take 10+ minutes but everything else is solved faster.

I don't have empirical evidence of this yet, I guess I should put together some sort of test to confirm/disconfirm this.