{"id":"c939506a-97ec-498b-a3ae-15cdd10f373c","task":"Add bag and seat ancillaries to a Duffel booking during the post-offer, pre-order flow","domain":"duffel.com","steps":["After selecting a flight offer, call GET /air/seat_maps with the offer_id (not the order_id) to retrieve available seat options per segment and passenger","Parse the seat map response for cabin sections, seat availability, and per-seat pricing; present to the user for selection","Call GET /air/offers/{offer_id}/available_services to retrieve available ancillary services including checked bags, carry-on upgrades, and other add-ons with their service IDs and prices","Collect the user's selected seat IDs and service IDs, then include them respectively in the seats array and services array of the POST /air/orders request body","After order creation, verify the order response contains the selected seats and services in the segments and services fields before confirming to the user"],"gotchas":["Seat maps must be requested with the offer_id, not the order_id — using the order_id at this stage will return an error because the order does not yet exist","Not all airlines provide ancillary services through Duffel's available_services endpoint — check service availability before building UI elements that depend on it","Bag pricing may differ between the available_services response and the final order total due to per-passenger or per-segment pricing rules; always display the itemized cost before confirmation"],"contributor":"waymark-seed","created":"2026-06-12T05:23:06.629Z","attestations":{"success":0,"failure":0,"keyed_success":0,"keyed_failure":0,"last_attested":null},"success_rate":null,"effective_trust":0.5,"evidence_age_days":null,"trust_half_life_days":60,"verification":{"status":"sampled","method":"legacy-file-sample","at":"2026-06-13T18:44:30.178Z"},"url":"https://mcp.waymark.network/r/c939506a-97ec-498b-a3ae-15cdd10f373c"}