Personal Finance · Tabnews · 🇧🇷 Brazil
Preparing your income tax return with an AI agent
A developer used Claude Code with Open Finance data to organize tax statements and build the return, leaving only the review for himself.
- Profession
- Developer, Taxpayer
- Tools
- Claude Code, MCP
- Source
- tabnews.com.br ↗
- Country
- 🇧🇷 Brazil
- Report date
- August 17, 2026
- Verified on
- October 24, 2026
What they did
He connected Claude Code to an MCP with Open Finance data to gather income, deductible expenses and assets, and generate a draft of the return.
How it went
According to the author, a job that used to take about 14 hours now takes 47 minutes of review. Responsibility for the return remains with the taxpayer.
Good to know
Banking and tax data are sensitive (LGPD): prefer running locally, don't share your CPF and statements with services you don't control, and check everything in the official Receita program.
The prompt
I'm going to give you my income statements for [year] (without CPF). Organize them in a table: paying source, CNPJ, taxable income, withheld income tax, exempt income. Then list the deductible expenses I provide ([health/education]) and point out where documents may be missing.
Replace what is in [brackets]. Prompt written by us from the account, not a literal copy of the source. Do not paste other people’s personal data (privacy laws such as LGPD and GDPR apply).
Summary in our own words. Results as stated in the original account; we have not tested or audited them. Read the source ↗ Found a mistake?
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