Have one agent write tax scripts and another check them
Idea + starter prompt, not run by us yet
For: Business owners who know their books well and want to check their own tax numbers
With QuickBooks exports and bank statements stored in a private repo, the author had Claude Code write Python that reads the records and works out the S-Corp return figures, and Codex reviewed them until both agreed. Codex flagged three issues, the worst a Schedule L line built from the wrong liabilities figure. He also found his own bookkeeping mistakes.
Steps
- Export your bookkeeping data and bank statements into a private repo or folder.
- Ask Claude Code to write scripts that compute each form line and show the source of every number.
- Have Codex review the scripts line by line and list any wrong mappings.
- Go back and forth until both agree, then check every result yourself.
- Have a qualified accountant review before anything is filed.
Starter prompt
I have bookkeeping exports in [folder] for [business type] for the year [year]. Write Python scripts that compute the figures for [tax form] from this data. For every line, show which source rows it uses and the rule you applied. Do not file, submit or send anything. Work only on copies of the files. Flag any line where the rules are unclear or the data looks inconsistent. I will have another reviewer and my accountant check the output.
Original post: common-sense.com · found via agentusecases.ai. Written up in our own words. We haven't run it, so test it on made-up data first.