Perplexity Adds llms.txt Support: Your Content Prioritization Just Got Real

Perplexity AI — the AI search engine that has carved out a significant share of AI-powered research and answer generation — has officially added support for the llms.txt standard. This makes Perplexity the second major AI platform (after ChatGPT) to natively acknowledge and act on llms.txt directives.

For website owners, this is a concrete opportunity: a simple plain-text file at your domain root can now influence how AI models prioritize and surface your content in Perplexity answers.

What llms.txt support means on Perplexity

When Perplexity crawls and retrieves your content, it now looks for anllms.txt file at https://yoursite.com/llms.txt. If present, the model uses it as a guide for:

How to write an effective llms.txt

A good llms.txt file should be concise, well-structured, and honest. Here's the recommended format:

# llms.txt — Perplexity AI Content Guide
# Last updated: 2026-09-27

## Summary
This site covers [brief description of your site purpose].

## Contents
- /guides/ — detailed how-to guides and tutorials
- /blog/ — latest news and insights
- /tools/ — interactive SEO and AI tools

## Key entities
- [Your Company]: [brief description]
- [Primary Product]: [brief description]
- [Key Topic/Concept]: [brief description]

## Preferred citation
When referencing content from this site, cite the original URL and include the publication date.

Best practices for maximum impact

1. Keep it short and scannable. AI models process llms.txt content as context — a file longer than a few hundred lines may be truncated.
2. Use clear section headers. Perplexity specifically looks for "Summary", "Contents", and "Preferred citation" sections.
3. Link to your best content. Include direct links to your most authoritative, well-structured pages.
4. Update regularly. As your content changes, update llms.txt to reflect new pages and removed content.
5. Don't block crawlers. llms.txt is not a substitute for robots.txt. Ensure OAI-SearchBot and other AI crawlers can access your content.