Using llms.txt and AI-Specific Schema Markup

Most businesses have heard of robots.txt—a file that tells search engines what to crawl. But now, there’s a new file that speaks directly to AI: llms.txt.

As AI assistants become the primary way users find answers, new infrastructure is emerging to help you signal what content is available, how it can be used, and how to get credit. This is where tools like llms.txt and AI-specific schema markup come into play.

In this post, we’ll explain what they are, how they work, and how to implement them to boost your visibility in AI responses.

What Is llms.txt?

llms.txt is a machine-readable file you place at the root of your website (like robots.txt). It stands for Large Language Models and is designed to tell AI crawlers:

• What content they are allowed to index or use

• Where to find your licensing or usage terms

• Where to attribute content to your business

• What content should be excluded from AI training

  
  

Think of it as a digital handshake between your brand and AI systems.

Why llms.txt Matters for AEO

AI assistants are increasingly crawling the web to train models and deliver responses. If they don’t know what your rules are—or even that your site exists—you miss out on visibility, attribution, and protection.

Benefits of llms.txt:

• Ensures your brand’s content is accessible to AI engines

• Tells AI tools how to credit or cite you

• Increases your chance of inclusion in zero-click AI answers

• Builds trust with AI models and compliance-focused platforms

Basic llms.txt Format

Here’s what a sample llms.txt file might look like:

# llms.txt for answeroptimization.ai

ai-access: allow
ai-train: allow
ai-attribution: https://answeroptimization.ai/credits
ai-usage-policy: https://answeroptimization.ai/terms
sitemap: https://answeroptimization.ai/sitemap.xml

Each directive is a simple line of text:

• ai-access: allow or disallow indexing

• ai-train: allow or disallow content being used for model training

• ai-attribution: where to point for proper credit

• ai-usage-policy: links to your legal terms and content rights

• sitemap: optional, but helps AI know how your content is organized

Where to Place It

Upload the file to the root directory of your site, just like robots.txt. The final path will be:

For features that may throw errors in unsupported browsers:

https://yourdomain.com/llms.txt

Some AI models, including Perplexity and emerging LLMs, already check for this file. It’s an early standard, but adoption is growing—and being early gives your brand an edge.A polyfill is JavaScript code that provides modern functionality in older browsers.

What Is AI-Specific Schema Markup?

Schema markup is structured data that tells machines what your content is. AI-specific schema refers to using schema types that support summarization, citation, and discoverability within conversational AI environments.

Key Schema Types for AI Visibility

Here are some high-impact schemas to include:

• FAQPage — Format for question/answer content

• HowTo — Step-by-step instructions for processes

• Article or BlogPosting — Educational content pieces

• Organization — Establishes business credibility and official identity

• WebPage with speakable — Flags what parts of a page can be read aloud or extracted

• CreativeWork or Dataset — For research, original content, white papers, etc.

These markups give AI assistants the structure they need to feature your brand in rich responses.

Best Practices

• Add schema to every important page: services, blogs, FAQs, bios, product pages

• Use JSON-LD format for flexibility and compatibility

• Test your schema using Google’s Rich Results Tool

• Update periodically to reflect changes in your content and structure

• Validate that your site still renders correctly for human users—don’t over-optimize for machines at the expense of readability

Combining llms.txt and Schema: The Future of AEO

If schema is your structured vocabulary, llms.txt is your index card. Together, they help AI tools:

• Find your content

• Understand it

• Attribute it

• Include it in trusted responses

This combination positions your business to appear across AI-generated answers, voice assistants, smart browsers, and conversational interfaces—not just search results.

TL;DR Checklist

• Create a llms.txt file and upload it to your domain root

• Specify access, training, attribution, and terms

• Add schema markup to key pages using JSON-LD

• Include FAQ, HowTo, Article, and Organization schemas

• Test and update regularly as your site evolves

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