Claude found the tax mistake their CPA made. The return is being amended.
They replaced their bookkeeper with Claude connected to QuickBooks. Asked to check last year's return, it found the CPA hadn't depreciated goodwill from an acquisition, and the CPA agreed.
Done withClaude CodeSpotted· by HN user idopmstuff· Oct 15, 2026
Result A clean rerun missed the same deduction
“when I gave it the tax docs I gave to my CPA for 2024's taxes plus my return, and asked it to find mistakes, it determined that he did not depreciate goodwill from an acquisition.”
Spotted: found in the wild. Details are as reported by the source above and have not been independently verified.
What they did
Uses Claude Code across the business: building internal apps, working with their software through APIs, and general use. Fired their bookkeeper and now uses Claude with a QuickBooks Online API key. Gave it the tax documents they had given their CPA for 2024, plus the return, and asked it to find mistakes.
How it went
It found the CPA hadn’t depreciated goodwill from an acquisition. The CPA confirmed the error and is amending the return. In a clean test with no prior context, it rebuilt the 2024 return almost entirely correctly but missed that same deduction, which convinced them that accumulated context leads to better results.
Try it yourself with Claude Code
Here are the documents I gave my accountant for [year] and the return they filed: [files]. Check the return against the documents for missed deductions, depreciation (including goodwill and assets from acquisitions), misclassified income and arithmetic errors. For each issue, cite the line, the rule and the likely amount, and say how sure you are. Write it up as questions I can send my accountant.
A starting prompt written by Agents in the Wild. Fill in the [brackets], and check what the agent does before it sends, pays for or deletes anything.
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