
Is llms.txt Mandatory For AI Search Visibility?
No engine requires it, Google's Search team says skip it, and Chrome's Lighthouse now audits it anyway. The full answer, plus the list of what actually is mandatory.
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Showing posts tagged “GEO” · 92 articles

No engine requires it, Google's Search team says skip it, and Chrome's Lighthouse now audits it anyway. The full answer, plus the list of what actually is mandatory.

A founder-to-founder answer to the llms.txt question: what the logs and citation data say, the steelmanned believer case, and where your four hours should go.

The disambiguation the industry owes you: five overlapping acronyms, one practice, two genuinely different meanings of AIO, and which words to use when.

Ten lessons from running an answer-engine content operation at scale: what compounded, what evaporated, and what I'd do differently starting today.

The definition, the four metrics that compose it, how to measure it across seven engines, and the levers that actually move it. The glossary entry, done right.

Perplexity is the citation-first answer engine. What it is, how its retrieval works, what it rewards, and how to earn a place in its answers.

Probably not for citations, maybe for navigation. A decision framework by site type, fresh adoption data, and the five rules if you do add the file.

GPT-5.6 broke half the GEO playbook. The strategies that survived: source citing, passage-level answers, docs, entity trust, and weekly measurement.

Discipline by discipline: what carries over from SEO unchanged, what changes shape for AI search, what's genuinely new, and what quietly dies.

The three optimization pillars that decide AI citations: page structure engines can lift, sources that make claims citable, and brand signals retrieval trusts.

A five-layer AI search readiness checklist: crawler access, rendering, extraction structure, entity trust, and measurement, with pass criteria.

We tested llms.txt on 12 sites for 90 days and got nothing. After GPT-5.6 rewired retrieval, here's the honest verdict on the file everyone still asks about.
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