Structured data describes visible facts
JSON-LD gives machines an explicit representation of entities and page content. Select a type that genuinely matches the page instead of choosing markup only because a search feature looks attractive.
Accuracy comes before eligibility
Names, URLs, dates and relationships should agree with the content visitors can see. Valid syntax is necessary, but search engines apply additional policies and decide whether enhanced presentation is appropriate.
Generate, validate and monitor
Create the smallest accurate object, validate its structure and then run the published URL through relevant official testing tools. Recheck markup when templates or visible content change.