Hey, I'm Damon Millar. I'm an accountant, fractional CFO and business advisor working with UK business owners, and I spend a lot of my week inside other people's Xero files.
I built this because cleanups are the worst-priced job in a practice. The price gets fixed before anyone knows what the work is, and the difference comes out of your margin. This is the workflow I use to find out what the job is before quoting it, and to take the hours of looking out of the work itself.
By the end you'll have a scored file, a defensible quote, a written workplan, a client question list, drafted correction journals waiting for review, and the checklist that stops the file going back to the same state next year.
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If you want to talk through how this fits your practice, book a call: Book a 30 minute call with Damon
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Claude on a paid tier, running Fable 5.1. The cleanup is a long-running job across thousands of rows. Fable 5.1 came out on 1 September 2026, and Anthropic's own numbers put it at 55.8% on Terminal-Bench 4.0 against 42.0% for Fable 5, with the stated improvement being that it holds focus across extended tasks instead of losing the plot halfway. That is exactly the failure mode that made earlier attempts at this useless.
A Composio account. Composio is the layer that gives Claude structured access to Xero without you handing over credentials.
Adviser-level access to the client's Xero organisation.
Your engagement letter checked for AI and subprocessor wording. See the house rules below before you connect anything.
A named approver in your firm. One person signs off every journal before it is posted.
Around 90 minutes for your first file. Faster after that, once your firm's thresholds are set.
Check your engagement letter and privacy notice cover the use of an AI subprocessor on client data. If they don't, fix that before the first connection, not after.
Check the current PCRT guidance on AI and technology before you build this into chargeable work. Guidance exists and it is on the professional bodies' sites.
Anonymise where anonymising costs you nothing. Account codes, amounts and dates do the analytical work. Contact names rarely add anything to a coding review, and you can pull them separately when a specific query needs one.
Name one approver. Claude drafts journals. It does not decide that a journal is right. A qualified person reviews every entry, and their name goes on the log in Step 7.
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Never let the model post into a locked or filed period. The toolkit cannot see what you have filed. You check the period lock in Xero before anything is posted.
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