Obtain SMC3 API credentials and confirm your subscription includes the CzarLite rating engine for the tariff base you need (e.g., CzarLite 2025 or a specific carrier tariff).
Build the rating request: origin zip/city/state, destination zip/city/state, shipment date, and one or more commodity lines each with NMFC item number, freight class, weight, and packaging type.
Submit the rate request to the SMC3 rating API; the response returns a line-haul charge, fuel surcharge basis, and any applicable tariff discounts as separate charge components.
Apply your negotiated carrier discount percentages (if managing through SMC3 contract terms) to the base rate to derive a net estimated carrier cost.
Compare the CzarLite-derived benchmark rate against carrier-quoted rates to identify overcharges or to set audit thresholds for freight invoice validation.
Known gotchas
CzarLite rates are a published benchmark tariff, not a carrier's actual contract rate; the SMC3 rate is used for benchmarking and audit, not as the rate you pay — your negotiated discount off the carrier's base tariff may differ from CzarLite.
NMFC item numbers are versioned; the NMFC publishes periodic updates that can reclassify items — always reference the current NMFC publication year in your rating request to ensure the class lookup is current.
The SMC3 API distinguishes between inter-state, intra-state, and inter-regional moves, each potentially governed by different tariff rules; confirm the correct rate basis type for the origin-destination pair.
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