In Part 3 of our series on "Structuring Historical Intelligence," we move beyond the challenge of preventing hallucination to the practical reality of building a historical system. Once you have validated your facts and bounded your reasoning, how do you actually let users explore the past? The answer isn't a single chatbot. As we discuss in this episode, relying on one general-purpose AI interface for everything creates confusion about authority, making it impossible to distinguish between fact, interpretation, and speculation. Instead, we explore a multi-layered approach that builds distinct surfaces for distinct historical tasks. In this episode, we break down the five specific layers of a structured AI history project: 1. Archive Search (Access, not Interpretation): We discuss why keyword searches fail when historical figures use nicknames, euphemisms, and family shorthand. Learn how offline processing maps name variants to canonical people before storage, ensuring search results are deterministic and free of "semantic guessing".2. The Daily Page (Contextual Constraints): Historical letters often distort our perception by emphasizing emotion over context. We look at how "The Daily Page" aggregates letters, inferred locations, and official government records to force every analysis to start with a hard constraint: What do we actually know about this day?.3. The Data Room (Visual Analysis): Some historical questions—like physical proximity or changing sentiment—are easier to compute than to narrate. We explore how this layer uses AI to score sentiment and measure distance, presenting "analytical interpretations" via charts and timelines rather than prose.4. The Correspondence Network (Structure): Discover how this layer visualizes "mental presence" rather than relationships. By mapping mentions across the archive, the system reveals patterns of attention without claiming causality.5. The Lab (Controlled Invention): This is the only surface where hallucination is permitted. We discuss how the project isolates generative experiments—including "Gemini Gems" trained on specific writing styles, AI-generated audio readings, and playful "Instagram" anachronisms—ensuring that imagination never contaminates the factual layers.Join us as we analyze why AI should be treated as an instrument, not an author. By choosing the right tool for the right job—from normalization and aggregation to medium translation—we can build systems that allow us to observe and experience history without reintroducing epistemic risk. Keywords: AI in History, Digital Humanities, RAG, Structured Data, NotebookLM, Generative AI, Historical Analysis, Data Visualization, Hallucination Prevention, Archive Management, Sentiment Analysis.