An AI index is the corpus of web content that an AI system has crawled, processed, and stored for use in generating responses to user queries. Each AI platform maintains its own index — with different crawl coverage, freshness characteristics, and content quality filters.
Getting into the AI index is the technical prerequisite for AI citation. A brand whose content is not in a platform’s AI index — because it was blocked by robots.txt, rendered in inaccessible JavaScript, or simply not crawled — cannot appear in that platform’s AI-generated responses. Indexability and crawl accessibility directly determine AI index inclusion.