llms.txt generator and validator
Build a spec-compliant llms.txt from a short form, or paste an existing file to check its structure. Both run in your browser, and nothing you type is uploaded.
The structure report appears here as you paste.
Built and checked in your browser. Nothing you type is uploaded.
An llms.txt file is a plain-text, markdown-based index that tells AI models what your site is and where its key pages live. The format is simple: a single H1 with your site name is the only required part, a blockquote summary is the convention, and H2 sections list your key links. This tool writes that structure for you and validates a file you already have.
Be realistic about what it does. As of mid-2026, there is no confirmed evidence that mainstream AI search systems read third-party llms.txt files, and Google has said as much on the record. It is cheap to publish and useful for developer tooling, but it is not a ranking or visibility lever. For the full picture, read what llms.txt is, its format, and real examples.
Common questions
What is actually required in an llms.txt file?
Only one thing: a single H1 with your site or project name. The spec calls that the only required section. A blockquote summary right after it is a strong convention, and H2 sections listing markdown links are optional additions.
Where does the llms.txt file go?
At the root of your domain, served at /llms.txt, the same way robots.txt is. Some sites also publish a longer llms-full.txt, but that is a separate vendor convention, not part of the core spec.
Do AI systems actually read llms.txt in 2026?
There is no confirmed evidence that major consumer AI systems fetch third-party llms.txt files during search. Google's John Mueller said no AI system currently uses it. The clearest real use is developer tooling, where coding assistants may read a library's llms.txt. Treat it as low-cost, not a visibility lever.
Is llms.txt the same as llms-full.txt?
No. llms.txt is a short index of links. llms-full.txt is a separate convention, popularised by Mintlify, that inlines a site's full documentation. It is not part of the original llmstxt.org proposal, and adoption of it is inconsistent even among large docs sites.