[maleldil]

A human has taste. They learn over time from codebase patterns and develop a sense of when an abstraction can be reused, improved or refactored. Agents often generate repeated code because the original file wasn't added to the context, and it's up to a human reviewer to recognise this.

In my experience, an agent will rarely recognise a common pattern and lift it into a new abstraction. It requires a human with taste and experience to do it. For example, an agent will happily add a big amount if branches in different places of the codebase where a strategy pattern or enum would be better (depending on the language).

If you have a working prompt or harness that ameliorates this, I'd be glad to see it.