> "I'd make a standardized Markdown specification the new unit of knowledge for the software project. ... There would need to be automated pull-request checks verifying not only that tests pass but that code conforms to the spec."
Agree, this is how you make the development loop more deterministic and ultimately autonomous. It's how I've been using coding agents myself for the past few months (by building my own to support this natively [1]).
If you have a spec you approve/agree on, have an agent code against it, and then have a review phase verify the implementation didn't drift from the spec (either by adding or removing features), you get to a position where you can trust the outcome.
There's still a lot to be said about spec definition and what if during implementation gaps are discovered, and that's where HITL comes into play.