Look up the order a cart produced

Recovery lookup for a client that lost its Idempotency-Key — after a timeout, a crash, or a closed tab — and needs to learn whether the cart it was checking out was charged.

Use the cartId returned when the cart was created and an API key for the retailer where the order was placed. No customer authentication is required. Keep the cart ID on your server.

data holds at most one order — the latest the cart produced for that retailer. If no order is found for that cart and retailer, data is empty, whether the cart never became an order, the cartId is unknown, or the order belongs to another retailer. An empty result does not confirm that no payment occurred under another retailer.

The order’s status says what to do next. PROCESSING means the payment is still settling, so keep polling. FAILED means the payment did not complete. It is final, so stop polling and let the shopper pay again; their next attempt on the same cart becomes the order this lookup returns. Any other status is the order’s outcome, and GET /orders/{orderId}?cartId= returns that order in full.