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Audit · developer.mozilla.org

Dual-axis lens: Performance (Core Web Vitals, real Chrome users) + Citation-readiness (10-characteristic LLM checklist).

Axis 1 — Performance (Core Web Vitals)

Strong100%

Real Chrome user data (28-day p75). Mobile + desktop. Source: Google Chrome UX Report.

Mobile (phone)

LCPgood
1596ms
Largest Contentful Paint
INPgood
127ms
Interaction to Next Paint
CLSgood
0
Cumulative Layout Shift
FCPgood
1518ms
First Contentful Paint
TTFBgood
592ms
Time to First Byte

Desktop

LCPgood
967ms
Largest Contentful Paint
INPgood
38ms
Interaction to Next Paint
CLSgood
0
Cumulative Layout Shift
FCPgood
862ms
First Contentful Paint
TTFBgood
397ms
Time to First Byte

Deep dive: full developer.mozilla.org report · mobile · desktop

Axis 2 — Citation-readiness (LLM-discoverability)

Weak30%

10-characteristic checklist (Aleyda Solis). Server-rendered HTML parsed as a GPTBot/PerplexityBot would see it. HTTP 200 · 1117w body · 202ms fetch

Hard-block: recognizable, extractable, consistent, differentiated at 0.0. Without these, LLM citation is functionally impossible regardless of other scores.
AAccessible
100%
1117 words of static body content. Crawlers can extract.
BUseful
75%
Body=1117w · headings=13 · structured-data blocks=0. Heuristic for content depth + organization.
Fix: Add depth: longer body content, more H2/H3 sections, structured data blocks (Article, Dataset, DefinedTerm).
📋 Lift Useful by closing these specific gapstext
• Structured-data blocks: 0 (target ≥2 — add Article + Person OR Organization + WebPage)
FRecognizable
0%
Organization schema: ✗ · name ✗ · url ✗ · logo/image ✗ · sameAs ✗
Fix: Add Organization JSON-LD with name + url + logo + sameAs[] (≥2 public profile URLs).
📋 Paste in <head> as <script type="application/ld+json">json-ld
{
  "@context": "https://schema.org",
  "@type": "Organization",
  "@id": "https://developer.mozilla.org#org",
  "name": "Developer Mozilla",
  "alternateName": "(any old brand names, for SEO equity continuity)",
  "url": "https://developer.mozilla.org",
  "logo": "https://developer.mozilla.org/logo.png",
  "sameAs": [
    "https://twitter.com/YOUR_HANDLE",
    "https://www.linkedin.com/company/YOUR_COMPANY",
    "https://github.com/YOUR_ORG"
  ],
  "description": "(1-2 sentence elevator pitch for your brand)"
}
FExtractable
0%
0/4 H2s are quote-ready (≥25 chars, ≥5 words) · DefinedTerm ✗ · FAQ blocks=0
Fix: Rewrite H2 headings as quote-ready sentences (≥5 words, descriptive). Add DefinedTerm schema for key concepts. ≤1 FAQ block per page.
📋 Rewrite these 4 H2 heading(s) so LLM crawlers can quote them as standalone sentences (target ≥25 chars + ≥5 words)text
BEFORE:  <h2>Featured articles</h2>
AFTER:   <h2>Featured articles — [add 2-4 descriptive words so it reaches ≥5 words + ≥25 chars]</h2>

BEFORE:  <h2>Latest news</h2>
AFTER:   <h2>Latest news — [add 2-4 descriptive words so it reaches ≥5 words + ≥25 chars]</h2>

BEFORE:  <h2>Recent contributions</h2>
AFTER:   <h2>Recent contributions — [add 2-4 descriptive words so it reaches ≥5 words + ≥25 chars]</h2>

BEFORE:  <h2>Contributor Spotlight</h2>
AFTER:   <h2>Contributor Spotlight — [add 2-4 descriptive words so it reaches ≥5 words + ≥25 chars]</h2>
📋 Add DefinedTermSet schema for your key concepts (lifts Extractable +0.30)json-ld
{
  "@context": "https://schema.org",
  "@type": "DefinedTermSet",
  "@id": "https://developer.mozilla.org/#glossary",
  "name": "(your concept area) Glossary",
  "url": "https://developer.mozilla.org/glossary",
  "hasDefinedTerm": [
    {
      "@type": "DefinedTerm",
      "name": "(Term 1)",
      "description": "(1-2 sentence definition)",
      "inDefinedTermSet": "https://developer.mozilla.org/#glossary"
    },
    {
      "@type": "DefinedTerm",
      "name": "(Term 2)",
      "description": "(1-2 sentence definition)",
      "inDefinedTermSet": "https://developer.mozilla.org/#glossary"
    }
  ]
}
📋 Optional: add ONE FAQPage block per page (>1 triggers schema-spam penalty)json-ld
{
  "@context": "https://schema.org",
  "@type": "FAQPage",
  "mainEntity": [
    {
      "@type": "Question",
      "name": "What does this site do?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "(answer in 1-3 sentences)"
      }
    },
    {
      "@type": "Question",
      "name": "How is this different from alternatives?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "(answer in 1-3 sentences)"
      }
    }
  ]
}
FConsistent
0%
No Organization.name detected — brand consistency unscorable.
Fix: Brand name should appear in <title>, nav/header, and Organization schema. Same name everywhere.
📋 Brand name in <title>, <nav>, and Organization.name must matchhtml
<!-- in <head> -->
<title>(YourBrand) · (page-specific subtitle here)</title>

<!-- in <nav> -->
<nav>
  <a href="/" class="brand">(YourBrand)</a>
  …
</nav>

<!-- in Organization JSON-LD -->
"name": "(YourBrand)"
CCorroborated
50%
32 external links · 1 to authoritative sources (.gov/.edu/wikipedia/web.dev/etc.).
Fix: Cite ≥3 authoritative sources (gov/edu/wikipedia/standards bodies/peer-reviewed). Build off-site presence (Wikipedia citation, Reddit organic, LinkedIn).
📋 Add ≥3 outbound links to authoritative sources matching your topichtml
<!-- Pick 3-5 sources relevant to your domain. Examples by topic: -->

<!-- Web performance / dev -->
<a href="https://web.dev/articles/vitals">web.dev Core Web Vitals</a>
<a href="https://developer.mozilla.org/en-US/docs/Web/Performance">MDN Web Performance</a>
<a href="https://developer.chrome.com/docs/crux/">Chrome UX Report</a>

<!-- Schema / standards -->
<a href="https://schema.org/Organization">schema.org reference</a>
<a href="https://w3.org/TR/">W3C specifications</a>

<!-- Health / science -->
<a href="https://www.nih.gov/health-information">NIH Health Info</a>
<a href="https://www.cdc.gov/">CDC</a>
<a href="https://pubmed.ncbi.nlm.nih.gov/">PubMed</a>

<!-- Finance / business -->
<a href="https://www.sec.gov/edgar.shtml">SEC EDGAR</a>
<a href="https://www.federalreserve.gov/">Federal Reserve</a>
FCredible
20%
Person schema ✗ · sameAs=0 · /about or /methodology link=✓ · datePublished=✗ · dateModified=✗
Fix: Add Person schema with sameAs[] (≥2 profiles). Link /about + /methodology in nav/footer. Add datePublished + dateModified to Article schema.
📋 Add Person schema (operator/author identity)json-ld
{
  "@context": "https://schema.org",
  "@type": "Person",
  "@id": "https://developer.mozilla.org/about#author",
  "name": "(your full name — operator or primary author)",
  "jobTitle": "Founder",
  "url": "https://developer.mozilla.org/about",
  "sameAs": [
    "https://twitter.com/YOUR_HANDLE",
    "https://www.linkedin.com/in/YOUR_HANDLE",
    "https://github.com/YOUR_HANDLE"
  ],
  "worksFor": {
    "@id": "https://developer.mozilla.org#org"
  }
}
📋 Add datePublished + dateModified to your Article/WebPage schemajson-ld
"datePublished": "2026-01-15",
"dateModified": "2026-06-28"
FDifferentiated
0%
0 POV markers detected (e.g. "our view", "we found", "we recommend").
Fix: Add explicit POV sentences ("Our view: …", "We measured …", "We recommend …"). LLMs cite pages with stance more than encyclopedic neutrality.
📋 Add explicit POV sentences in the body text (LLMs cite pages with stance more than neutral encyclopedic content)markdown
> Our view: (your specific stance on the topic this page covers)

> We measured (a number you actually measured) and found (insight).

> We recommend (specific action) because (reason backed by your data).
DFresh
30%
dateModified ≤90d (schema)=✗ · Last-Modified header ≤90d=✓ · visible "updated YYYY" text=✗
Fix: Add dateModified to schema; serve Last-Modified header; render visible "Last verified YYYY-MM-DD" near content.
📋 Add visible "Last verified" stamp near contenthtml
<p class="text-xs text-gray-500">
  Last verified <time datetime="2026-06-28">2026-06-28</time>
</p>
📋 Add datePublished + dateModified to Article/WebPage schemajson-ld
{
  "@type": "WebPage",
  "datePublished": "2026-01-15",
  "dateModified": "2026-06-28"
}
📋 Set HTTP Last-Modified response header (web framework-specific)text
# Express / Node:
res.setHeader('Last-Modified', new Date().toUTCString());

# Next.js middleware (middleware.ts):
import { NextResponse } from 'next/server';
export function middleware() {
  const res = NextResponse.next();
  res.headers.set('Last-Modified', new Date().toUTCString());
  return res;
}
DTransactable
25%
1 affordance keywords · mailto=✗ · contact/pricing/signup link=✗
Fix: Make the citation actionable: clear CTA, contact page, pricing, or mailto. Visitors who arrive from an LLM citation should be able to act.
📋 Add a visible mailto contact (LLM citation arrivals need somewhere to act)html
<a href="mailto:contact@developer.mozilla.org">contact@developer.mozilla.org</a>
📋 Add a /contact or /pricing page link from your footer/navhtml
<footer>
  …
  <a href="/contact">Contact</a>
  <a href="/pricing">Pricing</a>
</footer>

Prioritized fixes with copy-paste code

Ordered by impact across both axes. Top 6. Click the snippet rows to expand the exact code to copy.

  1. high[extractable] Rewrite H2 headings as quote-ready sentences (≥5 words, descriptive). Add DefinedTerm schema for key concepts. ≤1 FAQ block per page.
    Lifts Extractable from 0.00 → 1.00 (gap 1.00).
    📋 Rewrite these 4 H2 heading(s) so LLM crawlers can quote them as standalone sentences (target ≥25 chars + ≥5 words)text
    BEFORE:  <h2>Featured articles</h2>
AFTER:   <h2>Featured articles — [add 2-4 descriptive words so it reaches ≥5 words + ≥25 chars]</h2>

BEFORE:  <h2>Latest news</h2>
AFTER:   <h2>Latest news — [add 2-4 descriptive words so it reaches ≥5 words + ≥25 chars]</h2>

BEFORE:  <h2>Recent contributions</h2>
AFTER:   <h2>Recent contributions — [add 2-4 descriptive words so it reaches ≥5 words + ≥25 chars]</h2>

BEFORE:  <h2>Contributor Spotlight</h2>
AFTER:   <h2>Contributor Spotlight — [add 2-4 descriptive words so it reaches ≥5 words + ≥25 chars]</h2>
    📋 Add DefinedTermSet schema for your key concepts (lifts Extractable +0.30)json-ld
    {
  "@context": "https://schema.org",
  "@type": "DefinedTermSet",
  "@id": "https://developer.mozilla.org/#glossary",
  "name": "(your concept area) Glossary",
  "url": "https://developer.mozilla.org/glossary",
  "hasDefinedTerm": [
    {
      "@type": "DefinedTerm",
      "name": "(Term 1)",
      "description": "(1-2 sentence definition)",
      "inDefinedTermSet": "https://developer.mozilla.org/#glossary"
    },
    {
      "@type": "DefinedTerm",
      "name": "(Term 2)",
      "description": "(1-2 sentence definition)",
      "inDefinedTermSet": "https://developer.mozilla.org/#glossary"
    }
  ]
}
    📋 Optional: add ONE FAQPage block per page (>1 triggers schema-spam penalty)json-ld
    {
  "@context": "https://schema.org",
  "@type": "FAQPage",
  "mainEntity": [
    {
      "@type": "Question",
      "name": "What does this site do?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "(answer in 1-3 sentences)"
      }
    },
    {
      "@type": "Question",
      "name": "How is this different from alternatives?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "(answer in 1-3 sentences)"
      }
    }
  ]
}
  2. high[recognizable] Add Organization JSON-LD with name + url + logo + sameAs[] (≥2 public profile URLs).
    Lifts Recognizable from 0.00 → 1.00 (gap 1.00).
    📋 Paste in <head> as <script type="application/ld+json">json-ld
    {
  "@context": "https://schema.org",
  "@type": "Organization",
  "@id": "https://developer.mozilla.org#org",
  "name": "Developer Mozilla",
  "alternateName": "(any old brand names, for SEO equity continuity)",
  "url": "https://developer.mozilla.org",
  "logo": "https://developer.mozilla.org/logo.png",
  "sameAs": [
    "https://twitter.com/YOUR_HANDLE",
    "https://www.linkedin.com/company/YOUR_COMPANY",
    "https://github.com/YOUR_ORG"
  ],
  "description": "(1-2 sentence elevator pitch for your brand)"
}
  3. medium[credible] Add Person schema with sameAs[] (≥2 profiles). Link /about + /methodology in nav/footer. Add datePublished + dateModified to Article schema.
    Lifts Credible from 0.20 → 1.00 (gap 0.80).
    📋 Add Person schema (operator/author identity)json-ld
    {
  "@context": "https://schema.org",
  "@type": "Person",
  "@id": "https://developer.mozilla.org/about#author",
  "name": "(your full name — operator or primary author)",
  "jobTitle": "Founder",
  "url": "https://developer.mozilla.org/about",
  "sameAs": [
    "https://twitter.com/YOUR_HANDLE",
    "https://www.linkedin.com/in/YOUR_HANDLE",
    "https://github.com/YOUR_HANDLE"
  ],
  "worksFor": {
    "@id": "https://developer.mozilla.org#org"
  }
}
    📋 Add datePublished + dateModified to your Article/WebPage schemajson-ld
    "datePublished": "2026-01-15",
"dateModified": "2026-06-28"
  4. medium[consistent] Brand name should appear in <title>, nav/header, and Organization schema. Same name everywhere.
    Lifts Consistent from 0.00 → 1.00 (gap 1.00).
    📋 Brand name in <title>, <nav>, and Organization.name must matchhtml
    <!-- in <head> -->
<title>(YourBrand) · (page-specific subtitle here)</title>

<!-- in <nav> -->
<nav>
  <a href="/" class="brand">(YourBrand)</a>
  …
</nav>

<!-- in Organization JSON-LD -->
"name": "(YourBrand)"
  5. medium[differentiated] Add explicit POV sentences ("Our view: …", "We measured …", "We recommend …"). LLMs cite pages with stance more than encyclopedic neutrality.
    Lifts Differentiated from 0.00 → 1.00 (gap 1.00).
    📋 Add explicit POV sentences in the body text (LLMs cite pages with stance more than neutral encyclopedic content)markdown
    > Our view: (your specific stance on the topic this page covers)

> We measured (a number you actually measured) and found (insight).

> We recommend (specific action) because (reason backed by your data).
  6. medium[fresh] Add dateModified to schema; serve Last-Modified header; render visible "Last verified YYYY-MM-DD" near content.
    Lifts Fresh from 0.30 → 1.00 (gap 0.70).
    📋 Add visible "Last verified" stamp near contenthtml
    <p class="text-xs text-gray-500">
  Last verified <time datetime="2026-06-28">2026-06-28</time>
</p>
    📋 Add datePublished + dateModified to Article/WebPage schemajson-ld
    {
  "@type": "WebPage",
  "datePublished": "2026-01-15",
  "dateModified": "2026-06-28"
}
    📋 Set HTTP Last-Modified response header (web framework-specific)text
    # Express / Node:
res.setHeader('Last-Modified', new Date().toUTCString());

# Next.js middleware (middleware.ts):
import { NextResponse } from 'next/server';
export function middleware() {
  const res = NextResponse.next();
  res.headers.set('Last-Modified', new Date().toUTCString());
  return res;
}
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