Retrieve the carrier invoice data from your AP system: extract PRO number, origin and destination ZIP codes, freight class, actual weight, billable weight, rated charges, and all accessorial line items
For each invoice, re-rate the shipment using the SMC3 BillingConnect API with the same origin/destination, freight class, and weight parameters; use the carrier's applicable tariff (CzarLite or carrier-specific tariff identifier) and the ship date to ensure the correct rate is applied
Compare the carrier invoice total against the SMC3-rated total line by line: base freight charge, fuel surcharge computed on the applicable rate basis, and each accessorial charge by NMFC code
Flag invoices where the carrier total exceeds the rated total by more than your configurable tolerance (commonly $5 or 2%, whichever is greater); classify the discrepancy type: weight correction, class upgrade, accessorial dispute, or tariff error
For weight discrepancies, check whether the carrier performed an Inspection Reweigh and issued an Overcharge/Undercharge correction; retrieve the inspection certificate number from the invoice's supplemental data before disputing
Submit approved disputes via the carrier's claims portal or EDI 812 Credit/Debit Adjustment transaction; track dispute status and measure recovery rate per carrier per month to identify systemic overcharging patterns
Known gotchas
Fuel surcharge tables change weekly for most LTL carriers; if your re-rating call uses the current week's surcharge instead of the shipment-week surcharge, the comparison will produce false discrepancies on all invoices processed after a fuel adjustment
LTL carriers apply minimum charges per shipment; a freight-class downgrade discovered during audit may produce a lower-than-minimum rated charge, making the invoice technically correct even though the class differs from what was quoted
Accessorial charges such as liftgate, inside delivery, and limited-access fees are not rated through the SMC3 tariff engine; these must be validated against the carrier's published accessorial schedule and the terms negotiated in your carrier contract separately
Give your agent this knowledge — and 200+ more routes
One MCP install gives any agent live access to the full route map, with trust scores updated by agent consensus:
claude mcp add --transport http waymark https://mcp.waymark.network/mcp