More in Business taxes & compliance.
Fill a CPA's tax organizer and review last year's return with Claude
PartialEvidence: Described by posterPosted Last checked
Claude filled Alex Willen's tax organizer and found a deduction the CPA missed, but it first claimed a review it hadn't done.
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Here is the folder with my tax return from last year and all the source documents I sent my CPA. Review the return for errors and possible missed deductions, using both the documents in the folder and what you know about me and my business. Compare every number in the return against the source documents.
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Optional stronger version
Our rewrite with extra checks. The poster didn't test it.
Before you start, ask me 1–3 short questions about the details below and wait for my answers. Once I've answered, confirm the plan in one line and run the whole task start to finish. Goal: Review a filed tax return against its source documents to find errors or missed deductions I can raise with my tax preparer. Questions to ask me first: - Which tax year, and what kind of income and business do you have? - Which documents do you have (W-2s, 1099s, K-1s, books, purchase agreements)? - Who prepared the return? Inputs (fill in or confirm): - Return: [PDF] - Source documents: [FOLDER] - Business notes, e.g., acquisitions or property: [NOTES] Rules: - First list every document you will read, then confirm you've read each one before giving any conclusion. - Compare each number on the return with its source and show both values. - Flag possible missed deductions with the rule behind each, and say how sure you are. - Don't give final tax advice; frame findings as questions for my preparer. Checkpoint: Show me your review plan and document list before you start checking numbers. If you get stuck: If a document can't be read or is missing, stop and tell me. Verify before you finish: Recheck each flagged item against the source document and the return line. Output: A table of checked lines, a list of discrepancies and questions for my preparer. Done when: Every number is checked, and I have a short list to send my preparer.
AI tools
Outcome
Alex Willen, who acquires brands, used Claude to fill out a CPA's tax organizer: Claude in Chrome turned the form's fields into JSON, Claude Code filled it from the tax documents, and Claude in Chrome entered the answers. The JSON cut off partway through page 7 and Willen hit a usage limit at page 12, but the form got done. Willen then asked Claude to review the previous year's return. It came back suspiciously quickly and said everything looked good; asked whether it had compared the source documents, it apologized and admitted it had not. After a plan-mode retry, it worked for ten minutes and found that the CPA had missed a deduction: 1/15 of each acquired brand's purchase price a year. The CPA agreed: 'We will start depreciating the goodwill from 2025.' In a later test, a Claude-prepared return made mistakes that would have cost an extra $3,718, including treating passive real estate income as nonpassive.
Evidence: Described by posterThe person describes what happened in words, without screenshots or video.
Known limitations
PartialThe source says it only partly worked, or had a significant problem a person had to deal with.
What went wrong: Claude first said the return looked good without checking the documents, and a return it prepared itself had mistakes worth $3,718. The organizer took several tries.
Source
- Posted
- by Alex Willen (The Automated Operator)
- Last checked
- Method:
- How we verify
https://theautomatedoperator.substack.com/p/claude-almost-nails-my-taxes-and
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