PageIndex takes a different approach to RAG. Instead of relying on vector databases or artificial chunking, it builds a hierarchical tree structure from documents and uses reasoning-based tree search to locate the most relevant sections. This mirrors how humans approach reading: navigating through sections and context rather than matching embeddings.
As a result, the retrieval feels transparent, structured, and explainable. It moves RAG away from approximate "semantic vibes" and toward explicit reasoning about where information lives. That clarity can help teams trust outputs and debug workflows more effectively.
The broader implication is that retrieval doesn't need to scale endlessly in vectors to be powerful. By leaning on document structure and reasoning, it reminds us that efficiency and human-like logic can be just as transformative as raw horsepower.