The nine classes
| Class | Typical evidence | Typical entry |
|---|---|---|
| Timing / cut-off | posting dates either side of period end | accrual on the late side |
| FX translation | different rates on the two postings | revaluation to policy rate |
| Rounding | many small lines vs one total | rounding adjustment within threshold |
| Bank charge | fee line adjacent to the payment | reclass to bank charges per agreement |
| Withholding / tax | certificate, 10 %/15 % gap | recognise tax credit |
| Discount / deduction | contract clause, short payment on time | credit note |
| Duplicate / misposting | two postings, wrong counterparty or account | reversal / reclass |
| Missing document | no match in the other side's files | request + interim accrual |
| Genuine dispute | contradictory emails, disputed line | summary for controllers; no entry |
How an explanation is built
The agent is given the unmatched item, the candidate documents found by reference and amount, and the relevant agreement clauses. It must return a class, a one-paragraph reason, a citation list (document, page, line or cell) and a draft entry — or decline with a question. Explanations without a citation are rejected by the pipeline and re-asked; if the second attempt also lacks a citation the item is marked needs a person rather than explained.
Recurring items
If an item was explained last period and reappears unbooked, it is shown as explained Q2, not booked instead of being explained again — the most common reason reconciliations feel like Groundhog Day.