"changing the structure of what Codex uses, the skills, the durable artifacts" is all it takes to turn Codex into a tax accountant with more than a 90% success rate on tax filings.

This was the finding from OpenAI FDEs John de Wasseige and Arthur Fernandes Araujo on how Tax AI learns in production.

Instead of just patching bugs manually, the team turns corrections into Codex skills and durable artifacts so the system stops repeating the same edge-case mistake.

"if you provide a correction, the next time, it can be effective"