Notes for CPAs, EAs, and tax firms on tax prep with a source for every number, reasonable compensation, and tax planning, written for the people who prepare and review the return.
Tax Preparation
Claude Code and Codex side by side for a CPA or EA firm's small internal scripts: instruction files, review, undo, ask-first settings and surfaces, in each vendor's words.
How a CPA or EA firm can use Codex, OpenAI's coding agent, to build small read-only checker scripts on Doe test files, with a person reading every diff.
How a CPA or EA firm sorts AI output into three kinds, writes the line task by task, handles a draft that crosses it, and records who moves it.
Build an AI instruction for tax-document work from six checkable parts, change it one part at a time with a change log, and version and retire it on purpose.
The full path from a client folder to an entry list the Reviewer can trace: what each step passes on, the gate before each hand-off, and what reopens.
How a CPA or EA firm sets ChatGPT's Chat and Work modes per task, what goes in the folder it can modify, and which plans OpenAI's training default covers.
Draft cited rows from copies of a client's K-1 packets with an AI tool, follow every attached statement to its page, then confirm each row by hand.
Draft a what-changed list with an AI tool's pass over copies of last period's final workpaper folder and this period's client folder, then check each row by hand.
Draft the missing-items list with an AI tool's pass over a copy of the client folder, checked against the Firm's expected-documents list, then send the client one plain request.
Five ways an AI tool's first pass goes wrong on tax documents, and a known-answer test folder to run for each before your Firm relies on the tool for a task.
A side-by-side of Claude and ChatGPT for tax-prep work: account terms, the modes each vendor names, folder access, and the guardrails a firm sets for both.
A readback routine for the Reviewer: what to read back first, what to sample, what sends an entry back to the Preparer, and how to record it before sign-off.