IMO this points to two things:

- You didn't have the agent plan and de-risk/experiment beforehand

- You didn't glance at the output

Working with agents is not very different from working with other engineers.

You write a design doc, share it with others, divvy up the work. You get to review some % of the code and make sure the implementation is reasonable. You leave comments for the important issues rather than trying to obtain pure/perfect code.

One of the biggest difference IMO is that you cannot really mentor an agent (other than prompting e.g. with AGENTS.md/skills)

Agents, just like engineers, can create needlessly complex code/systems. If you want a good result, you need to ask why did they do it X way and consider alternatives.