agentic-walkthrough

1# Agentic Walkthrough — take the program's seat
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3The stance is the whole method. You are not a reviewer standing outside the code with a
4checklist; you are the thing the source describes — the job, the stage, the handler — and
5you run it in your head, hop by hop, exactly as it would run, noticing every switch you pass
6and every place your output goes. Only then do you turn to the real system and make it show
7you that what you just walked actually happened. The principle: BE the executor, then make the
8executor prove itself.
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10Ordinary debugging starts from a failure — an error, a red test, a wrong number. This starts from
11the opposite and much quieter case: **everything reports success and you still do not know whether
12the work happened.**
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14That case is real and it is not rare. A stage that cannot do its work can still report `done`. A
15job can start, finish, write a trace, and pass its own verification while touching nothing. No
16test suite catches this, because no assertion in the suite is false.
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18Three moves, in order. How far to take each is your judgment — often the first cannot finish
19without the ones after it.
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21## 1. Walk the path — be the program, read, don't run
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23Put yourself where the code sits and go hop by hop from entry point to effect. You are reading,
24not executing, which is the whole point: a live run cannot show you the branch it never took.
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26Three questions at each hop are usually enough:
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