Build an AI Agent (From Scratch)

you own this product
  • MEAP began October 2025
  • Last updated October 2025
  • Publication in Spring 2026 (estimated)
  • ISBN 9781633434615
  • 375 pages (estimated)
  • printed in black & white

pro $24.99 per month

  • access to all Manning books, MEAPs, liveVideos, liveProjects, and audiobooks!
  • choose one free eBook per month to keep
  • exclusive 50% discount on all purchases
  • renews monthly, pause or cancel renewal anytime

lite $19.99 per month

  • access to all Manning books, including MEAPs!

team

5, 10 or 20 seats+ for your team - learn more


Look inside
Build a working AI agent that can reason, plan, and execute multi-step tasks!

LLM-powered AI agents are the next leap in applied AI, capable of reasoning and collaboration to achieve even complex, multi-step goals. Using new protocols like MCP and A2A, agents can use software tools, retrieve relevant knowledge, and adapt to feedback. This book guides you step by step in creating an AI agent from the ground up, with clear, detailed explanations you can follow to build your own custom assistants!

In Build an AI Agent (From Scratch) you will learn how to:

  • Implement a ReAct (Thought → Action → Observation) loop
  • Use MCP to integrate tools calls into your agent’s workflow
  • Agentic RAG for relevant responses
  • Create memory modules that store facts, context, and evolving goals
  • Enable agents to plan, reflect, and self-correct
  • Build specialized agents, including a code execution agent
  • Design multi-agent systems

In Build an AI Agent (From Scratch), bestselling author Jungjun Hur and AI expert Younghee Song guide you through creating a complete research assistant agent framework. You’ll learn how agents function under the hood—all without hidden abstractions, black boxes, or frameworks lock-in. You will implement each piece as you develop a mental model of how agents really work.

about the book

Build an AI Agent (From Scratch) is a step-by-step guide to creating a working AI agent, starting with the bare essentials and growing your AI into a full-featured, real-world system. You will connect your agent to powerful software tools, implement a reasoning loop, and then extend your agent with retrieval, memory, planning, reflection, and even multi-agent coordination. Along the way, you will work through production-grade code snippets, full prompts and configs, and “make it better” exercises that encourage you to extend and improve your system. By the final chapter, you will have built an end-to-end AI agent you can use as a foundation for your own projects.

about the reader

For Python developers and AI practitioners. All examples run on a standard laptop.

about the authors

Jungjun Hur is an AI and data engineer with experience in e-commerce and AI industries, where he has built production-ready AI applications and LLM-powered features. He is the author of the bestselling book Practical AI Application Development Using LLM.

Younghee Song is an AI consultant at PwC. She graduated from Hanyang University with a degree in Economics and Finance and holds a Master’s in Human Factors Engineering from Seoul National University.
choose your plan

team

monthly
annual
$49.99
$399.99
only $33.33 per month
  • five seats for your team
  • access to all Manning books, MEAPs, liveVideos, liveProjects, and audiobooks!
  • choose another free product every time you renew
  • choose twelve free products per year
  • exclusive 50% discount on all purchases
  • renews monthly, pause or cancel renewal anytime
  • renews annually, pause or cancel renewal anytime
  • Build an AI Agent (From Scratch) ebook for free
choose your plan

team

monthly
annual
$49.99
$399.99
only $33.33 per month
  • five seats for your team
  • access to all Manning books, MEAPs, liveVideos, liveProjects, and audiobooks!
  • choose another free product every time you renew
  • choose twelve free products per year
  • exclusive 50% discount on all purchases
  • renews monthly, pause or cancel renewal anytime
  • renews annually, pause or cancel renewal anytime
  • Build an AI Agent (From Scratch) ebook for free