Humans are also not trustworthy. So we build systems to capture their nondeterministic output and solve the issues that emerge.

Adding another agent to check the first one feels like putting a band-aid on a band-aid. If there is an issue with the third one, we adding a fourth one as well

I mean sure, you can add a third, and a fourth and a fifth one if ur ok with the added cost, latency and it actually helps. Redundancy is a core concept in software and CS and at the heart of making many systems, complex or otherwise, reliable.

YMMV, I’m pretty AI-pilled in the sense that I think AI is one of the most pivotal things humanity will ever invent, and it’s going to radically change our civilization over the next few decades (not necessarily for the better!)

But I wouldn’t say I “trust” these agents. The degree to which I double check their work depends heavily on the consequences if it gets something wrong. Not too dissimilar from another human dev in that sense.

So for the SaaS that supports my family, there are some things I have it build where I glance at the PR for a minute or two, but if it broke something on this admin page that only I see, there’s no real downside and I’ll find out pretty quickly next time I use it. And it’s fine 95% of the time, so it doesn’t feel like the best use of my time to double-check it carefully.

But for some of the complex internal flows where a bug could be both catastrophic and difficult to even discover for awhile, I still check it very carefully.

For a little one-off vibe coded demo thing like OP shared, I wouldn’t look at the code at all, I’d just have another agent check it and fix anything it finds. Very low stakes.

It's agents all the way down

I mean if each agent reduces probability of error by 90% then after 9 agents you would have “nine nines” of reliability.

Obviously maybe it’s not composable like that exactly in real world but that’s the intent of agents checking agents