Build a read-only AI bookkeeping assistant on QuickBooks Online with Codex or Claude Code
Connect QuickBooks Online through a developer app, have a coding agent build a read-only tool, give it your receipts and history, then hand it bookkeeping checks one task at a time.
What it takes
- Cost
- From $20/monthClaude Code: Included with Claude Pro ($20 a month billed monthly), Max, Team and Enterprise plans, but not the Free plan. You can also pay for API usage instead.Codex works too, per the source. You also need your QuickBooks Online plan.Price checked Oct 24, 2026 on claude.com. Prices change; check before you buy.
- Setup time
- An afternoonOur estimate from the source, for one business.
- Skill needed
- Some tech skillsComfortable installing an app, pasting an API key or running a command.
Explain it simply
You connect your accounting software to an AI coding assistant so it can read your transactions and reports, without changing anything. You also give it your receipts and invoices. Then you teach it your bookkeeper's checks one at a time, and your bookkeeper still reviews the results.
What you need
- A QuickBooks Online company you can connect with production keys.
- Access to where your receipts, invoices and agreements live (for example Google Drive, Gmail, Dext).
The author budgets about 20 minutes for the QuickBooks connection alone; the rest depends on how many tasks you hand over.
Steps
Create a QuickBooks developer app
In the QuickBooks developer portal, create an app, choose Accounting, and connect it to your real company using the production keys.
The author suggests having your AI walk you through this part.
Have the agent build a read-only tool
Open a project in Codex or Claude Code and ask it to build a tool that pulls your transactions and reports so it can review your books. Connect the app you just created.
PromptWritten by our editors from the sources Build a small tool that pulls my QuickBooks Online transactions and reports using the app credentials in [where they're stored]. Read-only access only: no creating, editing or deleting anything. Show me a test pull of last month's transactions before going further.Adapted from the instruction in the source post.
Give it the context behind the numbers
Connect Google Drive, Gmail, Dext and whatever else your team uses, and upload exports where needed.
It needs the receipts, invoices, agreements and instructions behind the numbers.
Pull your history and look for problems
The author pulled two years so it could compare this month with how things were handled before.
Ask it to check for duplicate charges, inconsistent categories, unusual expenses and changes to previous months.
PromptWritten by our editors from the sources Using [period] of transactions, list: possible duplicate charges, vendors booked to different categories over time, expenses that look unusual for us, and any changes made to months before [date]. For each, show the transactions and why it's flagged. Don't change anything.Hand over tasks one at a time
Start with reviewing expenses, then checking invoices, then finding missing information.
For each task, explain how your bookkeeper does it, check the result, save the instructions, then add the next task.
Teach it as you go
Correct it in plain words, such as which client has different payment terms or which category a charge belongs in.
Save those corrections as its playbook for the next run.
How to know it worked
- A test pull of last month matches what you see in QuickBooks.
- Its flagged items are ones your bookkeeper agrees are worth checking.
Watch-outs
- Keep it read-only. The author still has a bookkeeper who checks the work.
- Production keys open your real books; store them safely and never paste them into chats or code you share.
- The author offers his instruction file by DM; it isn't published, so these steps come from the post only.
Steps are written by our editors from the sources above. Test on low-risk work first. Spotted a mistake? Suggest a correction.