An extraction system that reports 97% accuracy and cannot tell you which 3% are wrong is not usable in finance, insurance or compliance. The value comes from knowing which outputs to trust.
We generate confidence at the field level using several independent signals rather than the model’s own self-assessment alone, which is unreliable on its own. Token-level probability from the extraction pass, agreement between two different model passes on the same field, validation against the document’s own arithmetic (do the line items sum to the stated total?), format and range checks, and cross-reference against master data — an unrecognised supplier tax ID is low confidence regardless of how cleanly it was read.
Those signals combine into a per-field confidence score, and thresholds decide the route. Above the threshold on every field: straight through. Below on any field: to the review queue with the uncertain fields highlighted. Thresholds are set per field by consequence, not uniformly — a misread invoice date costs a phone call, a misread bank account number costs real money, and they should not share a threshold.
The thresholds are tuned during parallel run, where we can measure precisely what STP rate each setting produces and what error rate slips through. That curve is a business decision, not a technical one, and we present it as such.