Agentic commerce
Structured data
Structured data is machine-parsable markup — usually schema.org vocabulary in JSON-LD — that states facts about a page explicitly rather than leaving them to be inferred.
On a commerce site the load-bearing type is Product with an Offer carrying price, priceCurrency, availability and an identifier. FAQPage, BreadcrumbList and Article matter for content pages, and Organization establishes the brand entity.
The failure mode worth naming: markup that asserts something the page no longer does. A stale price or an in-stock claim on a sold-out variant produces confident wrong answers from anything consuming it, and for Google rich results it risks a structured-data penalty. Generate it from the same source the page renders from, never by hand.