--- title: Structured data validator for AI agents description: Check whether your JSON-LD structured data is agent-extractable and trustworthy — not just valid Schema.org. last_updated: 2026-06-09 canonical_url: https://agent-ready.dev/structured-data-validator --- # Structured data validator for AI agents > Check whether your JSON-LD structured data is agent-extractable and trustworthy — not just valid Schema.org. Tests freshness, canonical, entity consistency, and extraction signal. ## What it checks A schema validator grades your markup for Google's rich-snippet pipeline. This tool asks a different question: is your JSON-LD agent-extractable and trustworthy? Two layers: **D1–D4 — schema lint (URL or pasted snippet):** - **D1** Parseable JSON-LD present - **D2** Recognised primary `@type` (unknown types warn, never fail — agents can still read them) - **D3** Core agent fields present (identity, description, URL, freshness) - **D4** Field values well-formed (dates parse, URLs are URLs) **D5–D8 — agent coherence (URL mode only; the part schema validators don't do):** - **D5 Freshness honesty** — JSON-LD `dateModified`/`datePublished` agrees with the page's `sitemap.xml` `` and a visible on-page date - **D6 Canonical & markdown coherence** — the JSON-LD `url` matches `` and a `/.md` markdown mirror exists - **D7 Entity-name consistency** — the Organization/site name matches across JSON-LD, `llms.txt`, and `AGENTS.md` - **D8 Extraction signal** — the primary entity has a description and the page ships real visible text, not an empty JS-rendered shell ## How it relates to validator.schema.org For full Schema.org vocabulary and Google Rich Results conformance, use [validator.schema.org](https://validator.schema.org/) and the Rich Results Test — those are the right tools for SEO rich snippets. This validator is the agent-readiness layer they don't cover: whether an autonomous agent can extract a fact from your structured data and trust it enough to cite. Run both. ## Frequently asked questions ### How is this different from validator.schema.org? validator.schema.org and Google's Rich Results Test grade your markup against the full Schema.org vocabulary and Google's rich-snippet eligibility rules — that's the right tool for SEO rich results. This validator answers a different question: is your structured data agent-extractable and trustworthy? It lints the basics (parseable JSON, recognised type, well-formed values) and then runs checks the schema validators don't: does the JSON-LD date agree with your sitemap and visible date, does its URL match your canonical and a markdown mirror, does the entity name match your llms.txt and AGENTS.md, and is there actually enough content for an agent to quote. For full Schema.org conformance, use validator.schema.org; for agent-readiness, use this. ### What do the agent-coherence checks (D5–D8) look at? D5 (freshness honesty) compares the JSON-LD dateModified/datePublished against your sitemap.xml and a visible on-page date, flagging dates that don't agree. D6 (canonical & markdown coherence) checks the JSON-LD url matches your and that a /.md markdown mirror exists. D7 (entity-name consistency) compares the Organization/site name in your JSON-LD against your llms.txt and AGENTS.md headings. D8 (extraction signal) checks the primary entity has a description and the page ships real visible text rather than an empty JS-rendered shell. ### Can I validate a JSON-LD snippet without a URL? Yes. Paste mode runs the four schema-lint checks (parseable JSON, recognised @type, core agent fields, well-formed values) on a snippet directly. The four agent-coherence checks need a live page to compare against (sitemap, canonical, llms.txt, page text), so they only run in URL mode. ### Which @type should my page use? Use the most specific Schema.org type that fits: Article/BlogPosting/NewsArticle for content, Product for products, FAQPage for FAQs, HowTo for guides, Organization and WebSite for site-wide identity. The validator recognises the common types and is permissive about unusual ones — an unrecognised type is a warning, not a failure, because agents can still read it. ### Does a warning mean my structured data is broken? No. Failures are real defects (no parseable JSON-LD, malformed dates/URLs, no identity). Warnings are agent-readiness gaps — a missing recommended field, a freshness signal that can't be corroborated, an entity name that doesn't match your llms.txt. A warning marked 'could not verify' just means a corroborating source (sitemap, llms.txt) wasn't found, not that anything is wrong. --- Validate your structured data on the web: Related: [How to make your site AI-agent friendly](https://agent-ready.dev/how-to-make-your-site-ai-agent-friendly) ## Sitemap See the full [sitemap](https://agent-ready.dev/sitemap.md) for all pages on agent-ready.dev.