Give it what a reviewer would see: the invoice, the PO or work order, the scope of work, and your backup, like a sign-in sheet or a delivery receipt. It reads screenshots, rejection notes and PDFs.
Because it reads your invoice and your paperwork together, it can check the thing that most often stops a payment: whether what you’re claiming matches what was approved.
Fix what it flags against your own records, and run it before you submit, not after an invoice comes back.