LLM Agent Patterns: From Single Agents to Orchestrations

LLM Agent Patterns is a practical guide to building reliable LLM-powered systems. Rather than treating agents as black boxes, this book breaks them down into reusable architectural patterns you can understand, evaluate, and implement in practice. It covers the foundations of LLMs and transformers, then moves into core agent patterns, tool use, reasoning strategies, verification, multi-agent architectures, orchestration, memory, and the future of agent systems. Throughout the book, examples focus primarily on LangGraph, with LangChain introduced where relevant, while keeping the underlying ideas framework-agnostic. This book is written for developers, researchers, and students who want to move beyond basic prompting and learn how to design robust agentic systems that can reason, retrieve, act, and coordinate effectively.