Karin Ebert

I test two things separately, because passing validation and being correct are different questions and only one is usually checked. Structured data is declared in one of several syntaxes. JSON-LD is the one to use: it is a separate block that does not have to be written into the body, it does not depend on the page structure, and it is what tooling expects. Validation answers whether the markup is well formed against the vocabulary and the required fields. It says nothing about whether the values are true. A page can validate perfectly with a price copied from a different product, and the markup is then not merely useless but actively harmful, since a mismatch between declared and visible content is treated as a reason to ignore both. The rule I keep coming back to is that structured data describes what a reader sees. If a rating is not displayed on the page, marking it up is fabrication regardless of where the number came from. Eligibility is decided by the search engine rather than by the markup, so a page can be technically perfect and produce no result. I cover which types currently produce one, and the ones that do not. Types stack: a page can carry an article, a breadcrumb and a person together, as separate blocks, as long as they do not contradict each other. I keep a validation error separate from a mismatch error throughout this section. The first is a syntax problem you fix. The second is a factual one, and no amount of validation touches it.