Reads invoices, bills and receipts from PDF into structured JSON — vendor, customer, dates, PO, line items, discount, tax, shipping, total, balance due — and checks the arithmetic: quantity × unit price, lines to subtotal, tax rate, total and balance due. The response says exactly which figures don't add up. Returns vendor, customer, invoice number, dates, PO, line items, subtotal, discount, taxes, shipping, total, amount paid and balance due, plus checks (passed true/false, or null when the figures aren't printed). $0.04 per page (up to 25 pages) in USDC per successful read via x402, quoted before you pay; failed reads are free.