Pillar — full guide
A practical guide that lays out the different citation behaviors of ChatGPT, Claude, and Gemini, plus the measures that work for each. Uses observation data to explain why a one-size-fits-all approach is inefficient.
llms.txt and Schema.org; prefers structured informationAs a baseline, there is a "shared foundation" that improves citation rates for every AI. See GEO Implementation: The Complete Guide for details.
| Measure | Effect | Detail link |
|---|---|---|
Deploy llms.txt | Works for all AIs (+15–30pp) | llms.txt Implementation: The Complete Guide |
| Schema.org / JSON-LD | Works for all AIs (+10–25pp) | GEO Implementation: The Complete Guide |
| FAQ page design | Works for all AIs (+20–40pp) | Same as above |
| AI crawler support | Required for all AIs | Same as above |
Jumping straight to AI-specific optimization without these is doing things in the wrong order. First, ship 80% of the shared foundation, then move on to the AI-specific measures in this guide.
llms.txt (in GEO Meter observations, Claude's citation rate climbs +25–30pp for sites with llms.txt)llms.txtCompared to other AIs, Claude reads llms.txt strictly. Avoid abstract phrasing and narrow it to 5–10 concrete URLs plus descriptions.
✅ An llms.txt example that works for Claude:
> Sencha Lab is a sencha subscription service for businesses. From ¥3,800/month, with 200 corporate customers.
## Key sections
- [Pricing plans](https://...): Two plans at ¥3,800 / ¥7,600 per month
- [Customer stories](https://...): Monthly consumption and ratings from 5 corporate customers
- [FAQ](https://...): 30 questions on delivery / cancellation / tea leaves
Claude interprets Schema.org types such as Article, FAQPage, and Product accurately. Always include author / datePublished / dateModified.
{
"@context": "https://schema.org",
"@type": "Article",
"headline": "Five benefits of introducing sencha tea at your company",
"author": { "@type": "Person", "name": "Taro Yamada" },
"datePublished": "2026-04-15",
"dateModified": "2026-05-20",
"publisher": { "@type": "Organization", "name": "Sencha Lab" }
}
Claude values "the credibility of the citation source." It tends to prefer first-party information on the official HP over information funneled through third-party media.
→ Beefing up press releases, product pages, and the official blog under your own domain is highly effective.
Allow ClaudeBot and Claude-Web in robots.txt.
User-agent: ClaudeBot
Allow: /
User-agent: Claude-Web
Allow: /
ChatGPT has a marked tendency to cite Q&A from FAQ pages verbatim. Write a single clear A per Q, in natural language.
{
"@context": "https://schema.org",
"@type": "FAQPage",
"mainEntity": [
{
"@type": "Question",
"name": "How long can sencha tea be stored?",
"acceptedAnswer": {
"@type": "Answer",
"text": "We recommend consuming it within 1 year of the production date before opening, and within 1 month after opening."
}
}
]
}
ChatGPT (SearchGPT) often selects citation candidates from Bing search results as the base. Because indexing and ranking on Bing have indirect effects, traditional SEO cannot be ignored.
→ Registering sitemap.xml in Bing Webmaster Tools and optimizing <title> / <meta description> remain important.
ChatGPT tends to cite a composite of official + third-party media + Wikipedia.
→ Deliberately build up press distribution (PR TIMES and similar), contributions to note (a major Japanese long-form publishing platform), placements in industry media, and inbound citations into Wikipedia's references section.
User-agent: GPTBot
Allow: /
User-agent: OAI-SearchBot
Allow: /
User-agent: ChatGPT-User
Allow: /
Gemini feeds Schema.org into the Google Knowledge Graph, so structured data has the most direct impact.
Priority order:
Organization Schema (company info)Product / Service Schema (the products / services you offer)FAQPage SchemaArticle Schema (article pages)LocalBusiness Schema (stores / regional businesses)For local industries (tax accountants, beauty salons, restaurants, etc.), maintaining a Google Business Profile directly drives Gemini citations.
LocalBusiness Schema on the official HP and link to the Google Business URLBecause Gemini operates as the evolved form of Google Search, traditional SEO measures apply directly.
User-agent: Google-Extended
Allow: /
Google-Extended is the UA Gemini uses to access content for training and citation. Disallowing it removes you from Gemini's citation pool.
| Measure | Claude | ChatGPT | Gemini |
|---|---|---|---|
llms.txt | ★★★ | ★★ | ★ |
| Schema.org overall | ★★ | ★★ | ★★★ |
| FAQPage Schema | ★★ | ★★★ | ★★ |
| First-party content on official HP | ★★★ | ★ | ★ |
| Third-party media coverage | ★ | ★★★ | ★★ |
| Google Business Profile | — | ★ | ★★★ |
| Traditional SEO (links, etc.) | ★ | ★★ | ★★★ |
Cases like "cited on Claude but not on ChatGPT" come up routinely in GEO Meter data. If you only look at one AI, you risk pointing your strategy in the wrong direction.
GEO Meter observes Claude / ChatGPT / Gemini in parallel and lets you compare citation counts, rankings, and context per AI.
Each AI's citation logic differs, so being #1 on Claude but invisible on ChatGPT happens regularly. You need to address all three separately.
For Gemini, somewhat true. But Claude / ChatGPT are less influenced by SEO. The llms.txt / Schema.org / FAQ trio comes first.
Perplexity is not currently in GEO Meter's observation scope, but measures aimed at Claude / ChatGPT (llms.txt + Schema.org + third-party media) carry over almost directly. Treat it as medium priority.
llms.txt + Schema.org + FAQ) works for every AIllms.txt precision + first-party publishing + Article Schemallms.txtOnce you have read the article, check your own status. GEO Meter observes how Claude / ChatGPT / Gemini cite you in one pass.