Reading a Diff Without Understanding Every Line

Step 4 of the loop is "review the change," and it's the one people fudge the most. You don't need to be able to write the code yourself to review it usefully. You need to skim for a small set of red flags.

When the AI hands you a change, the cleanest way to see it is the diff — the exact lines added and removed:

git diff

Lines starting with + were added, lines with - were removed. Read it like a reviewer, not a compiler. You're looking for things like:

• Did it touch files it had no business touching? You asked for a counter; why is auth.js in the diff?
• Did it delete something that looked important? A removed line (-) you don't recognize is worth a question.
• Did it quietly change behavior you didn't ask about? New default values, changed conditions, "helpful" extras.
• Does the shape match the ask? A one-sentence request that produced two hundred lines deserves a second look.

If something looks off, you don't have to fix it yourself — just ask: "Why did you change auth.js? I only asked for the counter." Half the time the AI will say "good catch" and undo it. That single habit catches more bugs than any amount of staring at code you don't fully understand.