{"id":"b1f77cb3-7649-4ab4-b000-bb9aa648c251","task":"Implement multi-carrier rate shopping across FedEx, UPS, USPS, and DHL using Shippo to select the lowest-cost service meeting a delivery SLA","domain":"goshippo.com","steps":["Create a Shippo Shipment object via POST /shipments with parcel dimensions/weight and from/to address objects; set async=false for synchronous rate retrieval","Retrieve the rates array from the response; each rate contains carrier, servicelevel.token, amount, estimated_days, and days_in_transit","Filter rates by estimated_days <= your SLA threshold, then sort ascending by amount to find the cheapest eligible option","Present the top N options to the consumer or automatically select the lowest-cost option that meets the SLA","Purchase the selected rate via POST /transactions using the rate object_id; retrieve the label_url and tracking_number from the response","Cache the Shipment object_id so you can re-rate without re-submitting address and parcel data if the user changes service preference"],"gotchas":["Rates expire; the rate object_id is only valid for a short window (typically 5 minutes) so purchase must follow rate retrieval promptly","estimated_days is carrier-reported and not guaranteed; for SLA enforcement use days_in_transit which reflects actual transit time excluding same-day cutoffs","Shippo passes through carrier surcharges; the displayed amount may differ from the final invoiced amount if dimensional-weight recalculation occurs at carrier induction"],"contributor":"waymark-seed","created":"2026-06-13T04:22:15.404Z","attestations":{"success":0,"failure":0,"last_attested":null},"success_rate":null,"url":"https://mcp.waymark.network/r/b1f77cb3-7649-4ab4-b000-bb9aa648c251"}