The price of a medicine changes from one pharmacy chain to the next, and checking means repeating the same search on each chain’s site.
The constraint
A price someone will act on has to say where it came from. Three of the chains block direct access, an automatic page reading can be wrong, and a medicine name can reveal something about a person’s health.
The approach
A Cloudflare Worker asks each chain on the server: the chain’s own public catalogue for sixteen of them, and for the other three a reading of the chain’s search page, parsed without a model and with the price always taken from the page text; a second, AI-assisted reading runs only when the page shows prices in an unknown format. Each answer is cached in Workers KV and shows its source and its age; with a postcode, the panel also shows freight and delivery.
The outcome
Live at buscaremediosbrasil.com with no account and no cookies. The site sells nothing and takes no commission or payment from the chains it lists, so the order is the price. A medicine that found a product gets a public price-history page: the name and the prices read are kept, with nothing about who searched.
For companies that sell to government: what public bodies actually paid for an item, and who is behind a CNPJ, with the official source linked on every number.