Model identity first
Organization and WebSite entities establish who operates the site and which URL is canonical. Stable @id values let Service or WebAPI descriptions reference the same provider.
Describe real capabilities
WebAPI or Service markup can name the interface, documentation, provider, terms, and visible offers. Do not add ratings, customers, integrations, or guarantees that the product cannot substantiate.
Validate syntax and consistency
Parseable JSON-LD is necessary but insufficient. Compare names, endpoints, prices, currencies, and access requirements with HTML, OpenAPI, capability manifests, and payment challenges.