William doesn't start from scratch. It arrives with UK VAT rules built in from HMRC, and the moment you connect your ledger it keeps learning — your chart of accounts, your historical documents, how your firm codes transactions. Every correction sharpens it further.
But patterns have limits. Some things in your firm are policy, not pattern — a supplier that's always VAT exempt, Uber always coded to Travel. Rules like these shouldn't be inferred; they should be set. That's what Teach William is for.
Two ways to teach William
There are two layers — one for certainty, one for flexibility.
Fixed rules — for decisions with no room for interpretation. Set a category, tax rate, due date, or currency once and William never deviates.
Guidance — plain-language instruction for anything more nuanced. Write it the way you'd explain a quirk to a new team member: "Amazon orders vary — always check the line items. Office supplies → 520, IT equipment → 740."
Fixed rules always take priority over guidance. If a fixed rule and a guidance line both apply to a document, William follows the fixed rule.
What you can teach William about
Rules are organised by scope — where in your bookkeeping the rule applies.
Supplier — rules and guidance for a specific supplier. Set fixed rules (e.g. "Uber always coded to Travel") or plain-language guidance for what varies.
Category — guidance for a specific category in your chart of accounts (e.g. "Utilities: gas, electric, and water bills all go here").
Tax rate — guidance for a specific tax rate (e.g. "Apply No VAT only to HMRC payments, wages, and bank transfers").
General — firm-wide defaults that apply across every document.
Teach William shows every rule and piece of guidance you've set up for a company in one place.
William can suggest rules
William tirelessly watches where it gets things wrong — every gap in what it knows about this company — and surfaces them as suggested rules in Teach William.
Each suggestion shows:
The pattern William spotted, and how to fix it. For example: "Across 6 suppliers, General Expenses is consistently corrected to Travel & Subsistence — add guidance on General Expenses describing when this category should be used."
The documents the pattern is based on.
Every suggestion you act on closes a knowledge gap for good. William carries that lesson into every future document — and never forgets.
What's next
Teaching William sets the rules and guidance it follows. Tracking William's decisions shows you those rules at work — every call explained in plain language, for any document.
That's how you stay in control: you've set what William follows, and you can verify every decision yourself — not take it on faith.
Track William's decisions and the reasoning behind them — read William's reasoning for any document, and turn corrections into a permanent rule.
Meet William, your AI bookkeeping agent — back to the overview if you want to revisit what William does end-to-end.