Double-check a CPA-prepared draft tax return with ChatGPT and Claude and find two errors worth $2,686

Posted

Apr 5, 2026 by Katharine (Katie) Kormanik (LinkedIn)

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Last checked

Oct 17, 2026

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Method:

How we verify

Evidence: Described by posterThe person describes what happened in words, without screenshots or video.

Context: Using two AI tools as a cross-check is the poster's approach. The two errors aren't described, and the $2,686 is the saving the poster expects once they're corrected, not a confirmed refund.

Outcome

Before filing, Katie Kormanik ran a CPA-prepared draft tax return and all of their 2025 tax documents through both ChatGPT and Claude. Both found the same two errors, which once corrected will save them $2,686.

Agent

ChatGPT, Claude

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: Review my draft tax return against my tax documents and list anything that looks wrong or missing, so I can raise it with my preparer.

Fill in before running:
- The draft return (PDF): [UPLOAD]
- All tax documents for the year (W-2s, 1099s, receipts, etc.): [UPLOAD]
- Anything that changed this year (move, new job, child, sale of assets): [NOTES]

You're not my accountant or financial adviser. Show your working, label estimates as estimates, and tell me which points a professional or the official source should confirm.

Rules:
- Match every figure on the return to a source document and list any that don't match.
- Flag possible missed deductions or credits, with the form and line and the rule behind it.
- Estimate the money impact of each issue and label it as an estimate.
- Write the issues as questions for my preparer, not as conclusions.
- 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 table of possible errors (line, what's on the return, what the documents show, estimated impact) and a short note to my preparer.

You'll know it worked when: my preparer has checked and corrected any real errors before filing.

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: Review my draft tax return against my tax documents and list anything that looks wrong or missing, so I can raise it with my preparer.

Fill in before running:
- The draft return (PDF): [UPLOAD]
- All tax documents for the year (W-2s, 1099s, receipts, etc.): [UPLOAD]
- Anything that changed this year (move, new job, child, sale of assets): [NOTES]

You're not my accountant or financial adviser. Show your working, label estimates as estimates, and tell me which points a professional or the official source should confirm.

Rules:
- Match every figure on the return to a source document and list any that don't match.
- Flag possible missed deductions or credits, with the form and line and the rule behind it.
- Estimate the money impact of each issue and label it as an estimate.
- Write the issues as questions for my preparer, not as conclusions.
- Check facts that can change (prices, opening hours, dates, availability, rules) against the official source, and tell me anything you couldn't verify.
- Tell me which items you're least sure about.

Output: A table of possible errors (line, what's on the return, what the documents show, estimated impact) and a short note to my preparer.

You'll know it worked when: my preparer has checked and corrected any real errors before filing.

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://www.linkedin.com/posts/katiekormanik_ai-just-saved-me-and-my-husband-2686-in-activity-7446399497137672192-Pqwh