Free resources · Harness Engineering webinar
The Harness Engineering cheat sheet and agent requirements template
Two practical resources from the Harness Engineering session with Nicole Koenigstein: a guide to what the harness controls and how its parts affect each other, and a template for planning your own agent before you build it.
Get both resources
Harness Engineering Cheat Sheet
By Nicole Koenigstein
A high-level guide to what the harness is responsible for and why each part matters in production. It covers the anatomy of a harness, how state moves through it, verification and repair loops, a symptom-to-cause table for troubleshooting, and a build checklist you can run against your own system.
Agent = Model + Harness. The model proposes. The harness decides what the model sees, which proposals become actions, what state survives, how results are checked, and what happens after a failure.
Agent Requirements Document (ARD) template
By Ali Parandeh
Plan your agent's functional, performance, reliability and security requirements before writing code. Hand it to Claude Code or Codex to work through the design and the harness it needs.
Missed the live session? Watch the recording
About the authors
Nicole Koenigstein
AI Researcher and Practitioner, Agentic Systems
Nicole Koenigstein is an AI researcher and practitioner in agentic systems, focusing on multi-agent architectures, evaluation, safety and long-term system behaviour. She has served as an external evaluator for a European Commission AI Grand Challenge and advised IOSCO on generative AI in regulated environments. She is the author of AI Agents: The Definitive Guide and Transformers: The Definitive Guide (O'Reilly), Math for Machine Learning and Transformers in Action (Manning), and the forthcoming Harness Engineering (O'Reilly).
Ali Parandeh
CEng · CEO and Founder, Build Your AI
Ali Parandeh is a Chartered Engineer and AI software engineer. He is the author of Building Generative AI Services with FastAPI (O'Reilly, 2025) and is writing the Building Reliable AI Agents series for Manning. Through Build Your AI he helps engineering organisations take AI from pilot to production.
