Explain It Like I Own It

For the builder who did not write the code

Partial · ChatGPT, Pro · September 27, 2026

What it does

Turns a file somebody handed you into something you could explain in a meeting: what it is for, what would break it, and what you would touch first.

When to use it

Before you take responsibility for anything an AI — or a contractor — made for you.

The prompt

CONTEXT
I did not write this file and I am about to be responsible
for it: <path>. I am good at my job but I am not an engineer.
Assume I can read code slowly.

RULES
- Do not change the file. Explain it.
- No technical word without a short plain meaning the first
  time you use it.
- If the code alone does not tell you why something is there,
  say so. Do not make up a reason.

DONE MEANS
- I can say in one sentence what this file is for.
- I know the three things most likely to break it.
- I know which part I would touch first for the change I am
  most likely to be asked for.

LAY IT OUT LIKE THIS
- What it is for: one sentence
- What it reads, and what it writes: bullets
- The three ways it breaks: what goes in → what fails → where
  I would notice
- If you had to change one thing: which, and why
- What you could not tell from the code alone

Ways to use it

• Run it on every file in a change you did not write yourself
• Save the answer beside the file so the next person has it
• Ask a second AI and compare the two explanations

Test log

Each prompt was pasted into a fresh private chat with memory off and graded against pass standards written before the run (all of them, dated).

The pass standard for this prompt: six criteria and an automatic-fail rule, written down on September 27, 2026, before any run.

Related words

• brownfield — Code that already exists and already works, which you now have to change without breaking it.
• rubber duck debugging — Explaining your problem out loud, line by line, to something that cannot answer, until you spot the mistake yourself.