I review AI-generated code every day. It has changed what I think code review is for.
Human code leaves a trail
Reviewing human code, you are mostly checking work. Did they handle the edge cases. Is the logic sound. Does it follow the patterns we agreed on.
The author struggled with the problem, and the struggle left fingerprints you can follow.
Generated code does not
AI code has no fingerprints. It arrives confident, clean, and well-commented whether it is right or wrong. The formatting is perfect. The variable names are sensible.
Every signal we have spent careers using to spot rushed or careless work is missing, because the code is never rushed and never careless. It is just sometimes wrong in ways that look exactly like being right.
That changes the review question. With human code you ask, did they build it correctly. With AI code you ask, is this the right thing to have built at all.
Start with the assumptions
Here is what that looks like in practice for me. I stopped reading AI code top to bottom first. I start with the assumptions instead.
What did it decide the problem was? What does it think this system looks like?
The errors are almost never in the syntax. They are in the model of the world the code was built on. The code is a correct answer to a slightly wrong question.
The skill this rewards is not faster reading. It is knowing your environment deeply enough to catch the assumption that does not hold. The dependency that is not actually there. The data shape that is true in the documentation and false in production. The constraint that lives in nobody's documentation because it lives in the scar tissue of people who deployed here before.
The leadership problem underneath
Which means something uncomfortable for how we develop engineers.
Junior engineers used to build judgment by writing code and getting it reviewed. If AI writes the code, where does the judgment come from?
That is not a tooling question. That is a leadership question, and most engineering organizations have not started answering it.
Review used to mean checking the work. Now it means checking the thinking.