Real Agent Cases

Catch an error in a 4th-grader's textbook answer key, which ChatGPT first got wrong too (failure)

Posted
by Carlos Mendoza (@carlosatal)
Last checked
Method:
How we verify

Evidence: Screenshots or logsThe source shows screenshots, a transcript or the agent's output.

FailureThe source says the agent did not get the job done.

What went wrong: ChatGPT agreed with the wrong answer key until the parent pointed to the exact word.

Outcome

Carlos Mendoza's 4th-grade son marked only B and F as correct in a Santillana exercise on numbers up to the billions. The platform's solution marked B, D and F, but D said '9,615 rounded to the billions is 10,000', which is false. When Mendoza asked ChatGPT to review it, it first said Santillana was right, reading 'billions' as if it were 'thousands'. Only when Mendoza pointed to the exact word did ChatGPT acknowledge the error. The son had been right from the beginning.

Agent

ChatGPT

Prompt Recreated prompt

The source didn't share its exact prompt, so we wrote this from what it describes.

Run this task now, exactly as written below. Everything you need is here, so start straight away and only stop if something required is missing or a rule below tells you to.

Goal: Check whether my child's homework answer or the answer key is right, reading the question word for word.

Fill in before running:
- Photo or text of the question and all options: [ATTACH / PASTE]
- My child's answer and the official answer: [DETAILS]

Rules:
- Quote the exact wording of each option before judging it.
- Work each one out step by step, paying attention to units and words like thousands, millions or billions.
- Say clearly which answers are right and which are wrong, and why.
- If the wording is ambiguous, say so instead of picking one reading.
- Check facts that can change (prices, opening hours, dates, availability, rules) against the official source, and tell me anything you couldn't verify.

Output: A short, option-by-option check with the working shown.

You'll know it worked when: I know whether to tell the teacher the key is wrong.

Try this in:

This prompt has blanks to fill in, like [ATTACH / PASTE]. We'll copy it instead of filling it in, so you can edit it before you send.

Opens in a new tab. We don't see what you send.

These links are only a shortcut. We're not affiliated with OpenAI, Google or xAI, and your results may not match the source.

Optional stronger version

Our rewrite with extra checks. The poster didn't test it.

Run this task now, exactly as written below. Everything you need is here, so start straight away and only stop if something required is missing or a rule below tells you to.

Goal: Check whether my child's homework answer or the answer key is right, reading the question word for word.

Fill in before running:
- Photo or text of the question and all options: [ATTACH / PASTE]
- My child's answer and the official answer: [DETAILS]

Rules:
- Quote the exact wording of each option before judging it.
- Work each one out step by step, paying attention to units and words like thousands, millions or billions.
- Say clearly which answers are right and which are wrong, and why.
- If the wording is ambiguous, say so instead of picking one reading.
- Check facts that can change (prices, opening hours, dates, availability, rules) against the official source, and tell me anything you couldn't verify.
- End by restating the exact word that decides each option, so I can double-check it myself.

Output: A short, option-by-option check with the working shown.

You'll know it worked when: I know whether to tell the teacher the key is wrong.

Before you finish: re-read my goal and constraints, check your answer against each one, and list anything you assumed or couldn't confirm.

Source

https://x.com/carlosatal/status/2111517945386156108

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