How can agencies debug JSON-LD that validates but does not generate search enhancements?

First confirm the page is crawlable, indexable, and canonical, with markup present in the rendered document. Next distinguish Schema.org validity from eligibility for specific Google search features; each feature has its own supported types and required properties. Verify that markup matches visible content, is not stale or contradictory, and describes the correct entity. Review Search Console enhancement reports when applicable. Many valid types have no special rich-result display. Never infer an implementation failure solely from the absence of a visual enhancement.