Input HarborISSUE #39 of 46

structured data · json-ld · schema.org

FormaVSCaptain Invalid Input

Forma saysStructured data (JSON-LD via schema.org) describes your content to search engines for rich results.

A <script type="application/ld+json"> block describes the page as a typed thing — Article, Product, Recipe, Event — using the schema.org vocabulary. Search engines read it to build rich snippets: star ratings, prices, FAQ accordions, recipe cards.

JSON-LD is Google's preferred format because it's a self-contained block — no need to interleave attributes through your markup. Validate it with a structured-data testing tool before shipping.

Power-ups you unlock

JSON-LD block describes the page as a schema.org type
Powers rich results: ratings, prices, FAQs, recipes
Preferred over microdata — a single standalone block
Validate with a structured-data tester before shipping

Captain Invalid Input attacks — common mistakes

Structured data that does not match the visible page (a violation)
Invalid JSON (a trailing comma breaks the whole block)
Marking up content that is not actually present on the page

Boss battleAdd a JSON-LD block describing this page as an Article with a headline, author, and datePublished.

Example code

<!doctype html>
<html><head>
  <meta charset="utf-8"><title>structured data</title>
  <script type="application/ld+json">
  {
    "@context": "https://schema.org",
    "@type": "Article",
    "headline": "Learning Structured Data",
    "author": { "@type": "Person", "name": "the drewless" },
    "datePublished": "2026-05-28"
  }
  </script>
</head>
<body style="background:#06040d;color:#e6e0ff;padding:20px"><h1>Learning Structured Data</h1></body>
</html>

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