◇ Could this help me?
Yes, and this is the strongest single technique in this batch. The insight is precise: a specification never covers everything, the gaps get resolved silently, and those silent resolutions are exactly where generated work goes wrong without anyone noticing. Requiring the decisions to be written down as they are made converts an unreviewable output into something that can be checked in minutes, and it costs nothing because the agent is making the decisions regardless. General practice, with one correction of emphasis: the file format is a preference rather than the substance, and markdown works fine if the log needs to live in version control and be diffed, so adopt the decision log and choose the format to suit where it will live.
When you implement the specification I give you, keep a running decision log as you go. Record every decision you had to make that the specification did not cover, and for each one write what you chose, what the alternatives were, and why you chose it. Include the decisions that felt obvious at the time, since those are the ones I would never otherwise see. Keep it in a single file alongside the work, and at the end give me the three decisions you are least confident about so I know where to look first. Do not treat the log as optional if the task runs long: an undocumented decision is the thing I am trying to prevent.