Amazon

Amazon through HasData

Five tools. hasdata_amazon_search_getSearchResults takes a query, the other four take an identifier: asin for a product or its reviews, sellerId for a seller or that seller's catalogue.

Identifiers are marketplace-scoped

domain decides which Amazon you are reading, and an ASIN that exists on www.amazon.com often does not exist on www.amazon.de. The same goes for a seller id. When a lookup fails, check the domain before you decide the item is gone.

Destination changes the answer

deliveryZip and shippingLocation shift availability, price and the seller mix, not just the delivery line. A price comparison across locations is only honest if you pass the location deliberately and say which one you used.

Reading the payload

A search that matches nothing returns a successful result with an empty productResults array, so branch on length rather than waiting for an error. A live listing can come back without a usable currentPrice when the item is out of stock or sold only through other sellers, so treat the price as optional and say so instead of printing zero.

The reviews tool pages and filters: stars, reviewerType, mediaType and sortBy narrow the set at no extra cost, which beats pulling everything and filtering afterwards.