Presumably they didn't want to sit there and monitor Claude Code doing this for each of the 14 things they want done. Using a harness around Claude Code (or its SDK) is perfectly sane for this. I do it routinely. You just automate the entire process so that if you change APIs or you change the tasks, the harness can run and ensure that all of your sets are correctly re-done.

Sitting there and manually typing in "do thing 1; oh it failed? make it not fail. okay, now commit" is incredibly tedious.

They said they were copy/pasting back and forth. But regardless, what do you mean by "harness" and "sets"? Are you referring to a specific tool that orchestrates Claude Code instances? This is not terminology I'm familiar with in this context. If you have any link that explains what you are talking about, would be appreciated.