The Four-Index Reality: Why AI Search Isn't One Thing

Originally published on rikuq.com. Republished here for Dev.to's readers.

The most consequential SEO observation of 2026 is also the simplest: AI search is not one thing.

When you ask ChatGPT a question, it queries Bing. When you ask Gemini the same question, it queries Google. When you ask Claude, it uses Brave Search and Anthropic's own crawl. When you ask Perplexity, it queries an index Perplexity built and maintains itself.

Five visible AI search surfaces. Four genuinely different underlying indexes. Each behaves differently. Each cites differently. Each rewards different optimization. And most SEO tools in 2026 still treat AI search as a single rank.

This is the four-index reality, and it's the entire premise of how serious content visibility tracking has to work going forward. Citare — the AI-search visibility platform I built — is constructed entirely around it. This post is the why.