[{"_1":2,"_3":-5,"_4":-5},"loaderData",{"_5":6,"_7":8},"actionData","errors","root",{"_28":-5,"_38":-5,"_39":40,"_41":42,"_43":44,"_45":46,"_47":48,"_49":50,"_51":52,"_53":54,"_55":56,"_57":58},"routes/_store+/_readers+/email_author.$slug/route",{"_9":10,"_11":-5},"book",{"_12":13,"_14":15,"_16":17,"_18":19,"_20":21,"_22":23},"currentUser","id","Z2lkOi8vbGVhbnB1Yi9TdG9yZTo6Qm9va1Byb2R1Y3QvNzk5MDE","title","Architect Your Agent's Harness","state","published","contactAuthorMethod","email","aboutText","

An AI agent is code, not a prompt. The harness, the engineering layer around the model (tools, control loop, retrieval, memory, validation, guardrails), is what decides whether your agent hallucinates or wastes tokens. You do not fix those failures by editing the system prompt; you architect them into the harness.

This book takes one travel booking agent that demos well and breaks in production, and rebuilds its harness one technique at a time: grounded retrieval, semantic tool selection, guardrails in code, multi-agent validation, the memory pointer pattern, async handles, debounce hooks, evaluation, and observability. Every technique ships as runnable code with measured before-and-after numbers. Each chapter also shows you exactly what to tell an AI coding assistant to build that layer for you.

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Kick off your book project, get started with GhostAI, get better at marketing, or spend the day doing all three! Free live workshops on Zoom. Saturday, June 27, 2026.

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