SEO & GEO Checklist 2026: The Ultimate Guide for Google and AI

In 2026, showing up on the first page of Google is no longer enough: you need to be the source cited by Gemini, ChatGPT and Perplexity. This checklist merges the fundamentals of technical SEO with the requirements of GEO (Generative Engine Optimization) to secure your hybrid visibility.

Why is classic SEO no longer enough in the face of GEO?

Generative Engine Optimization (GEO) is the set of techniques aimed at optimizing a brand's visibility in search engines powered by generative AI. Unlike traditional SEO, which ranks pages, GEO aims to get your expertise extracted to feed summaries such as Google AI Overviews.

According to research published in the proceedings of the ACM KDD 2024 conference (GEO: Generative Engine Optimization), GEO tactics can increase the visibility of sources in generative engine responses by up to 40%. Google, for its part, confirms that there is no additional technical configuration required to appear in AI Overviews: SEO fundamentals remain the foundation.

At Fragments Studio, we have condensed this strategy into 12 actionable points split across four pillars. For the strategic context, see also our article on GEO and the transformation of SEO in 2026.

Block 1: The Technical Foundation (Speed and Readability)

Technology remains the bedrock. If a bot (classic or AI) struggles to read your site, it will never recommend you.

1. Core Web Vitals: VSI and INP in the green

Why it matters: In 2026, Core Web Vitals (LCP, INP, CLS) remain Google's benchmark for real-world experience. An interface that lags or jumps during loading degrades quality signals.

To provide a good user experience, aim for an Interaction to Next Paint (INP) below 200 milliseconds. Google Search Central, Core Web Vitals

How to test: Use PageSpeed Insights or the Search Console Core Web Vitals report (CrUX field data). Aim for an INP ≤ 200 ms.

Example: Defer the loading of non-critical scripts (trackers, chat) so that the text content becomes interactive in under one second. Details in our guide Core Web Vitals 2026: VSI and INP.

2. Semantic HTML structure

Why it matters: LLMs and search engines rely on HTML structure to prioritize information. Correct use of <article>, <main> and <section> makes it possible to distinguish the main content from the noise (footer, sidebar).

Prefer a single <h1> per page and nest headings without skipping levels. MDN, Heading elements h1-h6

How to test: Inspect your code with the W3C validator or visualize the heading hierarchy (H1, H2, H3).

Example: Use a single <h1> per page, followed by <h2> headings that ask real user questions.

3. XML sitemap and real-time indexing

Why it matters: To be cited by AI, your content must be fresh and easy to discover. An XML sitemap helps Google find your URLs; the <lastmod> element can serve as a crawl scheduling signal when it is accurate and consistent.

We use lastmod as a signal for scheduling crawls to URLs that we have previously discovered. For lastmod to be useful, it must reflect reality: a "last significant modification," not a cosmetic footer change. Google Search Central Blog, Sitemaps and lastmod

How to test: Submit your file through Search Console and check the date it was last read.

Example: Include the <lastmod> tag for each URL as soon as a significant editorial update is published.

4. Setting up the llms.txt file

Why it matters: llms.txt is the new standard (introduced in late 2024) that acts as a dedicated guide for AI agents, telling them which pages are a priority for training and citation. Google describes it this way in its Lighthouse documentation on agentic browsing:

The llms.txt file is an emerging convention used to provide a machine-readable summary of a website's content, specifically designed for LLMs and AI agents. Without this file, agents may spend more time crawling the site to understand its overall structure and main content.

The Lighthouse audit flags a server error if the file is inaccessible; a 404 remains not applicable (optional). For the format (H1, summary blockquote, H2 lists), see the llmstxt.org specification.

How to test: Check that yourdomain.com/llms.txt is accessible as plain text.

llms.txt template:

# LLMs Full Context
# https://www.fragments-studio.com/llms.txt

## Core Principles
- Focus on technical excellence and digital product strategy.
- Prioritize articles with recent statistics (2025-2026).

## Key Resources
- [Development Services](https://www.fragments-studio.com/expertises/agence-application-web-saas)
- [AI Integration Guide](https://www.fragments-studio.com/blog/post/comment-lancer-premier-projet-ia-pme-methode-4-etapes-2026)

To go further, see our llms.txt and robots.txt guide for AI indexing.

Block 2: Content (Credibility and Extraction)

Content no longer just needs to be read; it needs to be "extractable."

5. FAQs marked up with Schema.org

Why it matters: Question/answer blocks structure information in an extractable way, which is useful for AI Overviews and assistants. FAQPage JSON-LD markup explicitly flags each question/answer pair to the engine.

The FAQPage type indicates that the page is an FAQ with answered questions. There must be one FAQPage definition per page, with mainEntity containing at least one valid Question. Google Search Central, FAQ markup

Note: Google removed FAQ rich results from the SERP (2026), but the markup remains useful for generative engines that extract question/answer pairs.

How to test: Test your URL with Google's Rich Results Test tool.

Example: "What is the difference between SEO and GEO?" followed by an answer of 40 words maximum.

6. Dated and sourced figures

Why it matters: AI favors factual, sourced content. Google recommends content that inspires trust, with clear and verifiable sources:

Does the content present information in a way that makes you want to trust it, such as clear sourcing, evidence of the expertise involved, or background about the author? Google Search Central, People-first content

Don't say "many users"; say "68% of users in 2026" with a link to a recognized study (Gartner, INSEE, an industry report, etc.).

How to test: Check that every strong claim comes with a year and a link to a study.

Example: "According to the 2025 Gartner report, 80% of customer interactions take place through an agentic interface."

7. The Inverted Pyramid model

Why it matters: Give the answer in the very first sentence. The inverted pyramid model puts the most important information first, so the reader (or the AI) can stop after the first paragraph and still get the essentials.

The inverted pyramid presents the most important information first, followed by details in decreasing order of importance. University of Florida, News Writing (WC191)

How to test: Read only the first 150 words of your article. Do you have the answer?

Example: Start with "GEO is an optimization strategy..." rather than with a generic introduction about how the web has evolved.

8. E-E-A-T: Proof of hands-on experience

Why it matters: AI can simulate expertise, but not hands-on experience. Google extended E-A-T into E-E-A-T (Experience, Expertise, Authoritativeness, Trustworthiness): trust is at the center, and first-hand experience counts.

Does content clearly demonstrate first-hand expertise and a depth of knowledge, for example, actual use of a product, a visit to a place, or communicating what a person experienced? Google Search Central Blog, E-E-A-T

How to test: Have you included original screenshots, client anecdotes or internal quantified results?

Example: "At Fragments Studio, we reduced this client's TCO by 15% by migrating to a serverless architecture."

Block 3: Internal Linking (Navigation Path)

9. Descriptive, semantic anchors

Why it matters: Internal links tell search engines and AI which concepts are related. Google recommends descriptive, concise and relevant anchor text, not empty phrasing such as "click here."

Good anchor text is descriptive, reasonably concise, and relevant to the page that it's on and to the page it links to. Google Search Central, Link best practices

How to test: Your link anchors should contain strategic keywords and describe the destination.

Example: Prefer "Discover our advice on mobile app development" over "For our mobile offering, click here."

10. Maximum depth of 3 clicks

Why it matters: An architecture that is too deep makes discovery harder for crawlers. Google has a limited crawl budget: unnecessary or duplicate URLs waste crawling resources. The 3-click rule is not an official Google guideline, but a widely adopted SEO best practice for keeping strategic pages close to the homepage.

Without guidance from you, Google tries to crawl all the URLs it knows about. If many of them are duplicates or irrelevant, this wastes crawl time on your site. Google, Crawl budget management

The 3-click rule (an SEO best practice, not a Google guideline) is detailed in the Ahrefs guide to internal links.

How to test: Use a crawler such as Screaming Frog to check the "Crawl Depth" column and spot orphan pages or pages more than 3-4 clicks deep.

Example: Link your case studies directly from your homepage or your main blog.

Block 4: AI Citability (Pure GEO optimization)

11. Standalone definitions

Why it matters: For a block of text to be cited by a generative engine, it must be standalone and understandable out of context. Avoid "As mentioned above..."; each paragraph must carry its own definition or claim.

After reading your content, will someone feel they've learned enough about a topic to help achieve their goal? Google Search Central, People-first content

How to test: Copy and paste a paragraph into a blank document. Is it still informative?

Example: "An AI-First Agent is software designed to operate autonomously by using LLMs to orchestrate complex tasks."

12. Extractable data (Lists and Tables)

Why it matters: AI and search engines process structured data better: <ul> lists, HTML tables with <th>, or Schema.org Table markup. For richer comparative datasets, Google's Dataset markup remains the reference.

How to test: Turn your enumerations into bulleted lists (<ul>) or HTML tables with explicit <th> headers.

Example: A table comparing the costs of SaaS vs custom development over 3 years; see our analysis SaaS vs custom development: 3-year TCO.

Frequently asked questions

Does GEO replace SEO in 2026?

No, GEO complements SEO. Google states that SEO best practices still apply to AI Overviews and AI Mode, with no additional technical requirement. SEO drives clicks to your site; GEO strengthens your visibility when users first read an AI summary before clicking.

Is the llms.txt file mandatory?

Not for Google Search: the Lighthouse audit marks it N/A in the case of a 404, because providing it remains optional (llms.txt documentation). However, it is a useful convention for steering AI agents toward your priority content.

How long does it take to see results from a GEO strategy?

Timelines vary by platform: classic Google indexing (weeks to months) vs the freshness perceived by generative engines (often faster if the content is structured and updated). Regularly test whether your pages are cited in ChatGPT, Perplexity or AI Overviews.

Conclusion

The shift from SEO to GEO is the most significant transformation in digital marketing since the arrival of mobile. By applying this checklist, you are not just pleasing a ranking algorithm: you are making your know-how indispensable to the AI ecosystem.

Remember that technical clarity and authentic experience (E-E-A-T) are your two best assets for staying visible in 2026.

Ready to optimize your digital presence for the AI era?

The Fragments Studio team supports you in the technical and editorial overhaul of your tools to maximize your hybrid visibility.

• Discover our web development expertise for a site with flawless Core Web Vitals.
• If your project requires custom AI integration, our engineers are at your disposal.
• Get an initial estimate with our project estimator.
• Or contact us directly for an SEO/GEO audit.