Standards
We don't invent standards. Every check our scans run maps to a published one — and where the field is still forming, to the convention the industry is actually adopting. We tell you which is which.
Last reviewed 2026-06-10. This is the same methodology we apply to security and compliance at webauditfix.com/standards — grounded in external standards, mapped check-by-check.
The AI Readiness Index — criterion by standard
| Criterion | Tests against | Status |
|---|---|---|
| D1 Structured data & schema markup | Schema.org vocabulary · JSON-LD 1.1 (W3C) · Google structured-data guidelines | Established |
| D2 llms.txt & AI crawler directives | Robots Exclusion Protocol (RFC 9309) · llms.txt (llmstxt.org) · AI-bot vendor directives | Emerging |
| D3 Semantic HTML hygiene | HTML Living Standard (WHATWG) · Language tags (BCP 47) | Established |
| D4 Entity & knowledge-graph presence | Schema.org sameAs · Wikidata / Wikipedia entities | Established |
| C1 Extractable answer units | Schema.org FAQPage / Speakable · answer-engine practice | Emerging |
| C2 Anchor-level addressability | URI fragments (RFC 3986) · HTML Living Standard · W3C Text Fragments | Established |
| C3 Canonical claims & epistemic freshness | Canonical Link Relation (RFC 6596) · Schema.org dateModified / datePublished | Established |
| A1 Verified author identity | Schema.org Person · rel=me (IndieWeb) | Established |
| A2 E-E-A-T signals | Google E-E-A-T / helpful-content guidance · Schema.org | Established |
| A3 Content provenance & authenticity | C2PA content credentials | Emerging |
| P1 Core Web Vitals | Core Web Vitals (web.dev) · W3C performance APIs (LCP / CLS / Event Timing) | Established |
| P2 WCAG 2.2 AA & EAA compliance | WCAG 2.2 (W3C Rec) · European Accessibility Act (Dir. 2019/882) | Established |
| P3 Ground-truth-layer stability | HTML Living Standard · progressive-enhancement / server-rendering principle | Practice |
| AS1 Agent-usable surface (API / MCP) | OpenAPI Specification · API Catalog (RFC 9727) · Model Context Protocol · A2A | Emerging |
| AS2 Agentic defensibility | HTTP Message Signatures (RFC 9421) · OAuth metadata (RFC 8414 / 9728) | Established |
| AS3 AI-representation observability | Share-of-model measurement — practice, no ratified standard yet | Practice |
Agentic commerce — criterion by standard
| Check | Tests against | Status |
|---|---|---|
| Product & Offer data | Schema.org Product / Offer · Google merchant structured data | Established |
| UCP manifest | Universal Commerce Protocol — /.well-known/ucp (Google, ucp.dev) | Emerging |
| Agent payments | Agent Payments Protocol (AP2, Google) · Agentic Commerce Protocol (ACP, OpenAI/Stripe) | Emerging |
| Shopping-bot access | Robots Exclusion Protocol (RFC 9309) · shopping-agent vendor directives | Emerging |
The standards bodies & specifications
Established — ratified or widely adopted
- Schema.org
- JSON-LD 1.1 (W3C)
- Open Graph protocol
- Sitemaps protocol
- Canonical Link Relation — RFC 6596
- Web Linking — RFC 8288
- Robots Exclusion Protocol — RFC 9309
- HTML Living Standard (WHATWG)
- WCAG 2.2 (W3C Recommendation)
- European Accessibility Act — Directive 2019/882
- Core Web Vitals (web.dev)
- C2PA content provenance
- OpenAPI Specification
- OAuth Server Metadata — RFC 8414
- OAuth Protected Resource Metadata — RFC 9728
- API Catalog — RFC 9727
- HTTP Message Signatures — RFC 9421
Emerging — conventions & specs we track
- llms.txt
- Model Context Protocol (MCP)
- Universal Commerce Protocol (UCP)
- Agent Payments Protocol (AP2)
- Agentic Commerce Protocol (ACP)
Why we draw the line
Conflating a ratified standard with an invented file format is how you end up trusting something that has exactly one implementer. The Established set is governed by neutral bodies — W3C, IETF, WHATWG, the EU — with real multi-vendor adoption. The Emerging set is genuinely useful and worth implementing early, but it is still moving: specs are versioned, partners shift, and details change. We track those changes and re-review this page as they land. What we don't do is dress an opinion up as a standard.
See the framework these standards underpin: the AI Readiness Index →