Daniel Costea

Daniel Costea is a software engineer with more than 20 years of experience in enterprise systems, product development, and developer training. He has been a Microsoft Most Valuable Professional (MVP) since 2019, recognized by Microsoft for his contributions in AI and .NET technologies. Daniel speaks frequently at technology conferences, has trained hundreds of developers, and created multiple courses on the practical, production-ready use of the modern .NET ecosystem.

books by Daniel Costea

Building AI Agents in .NET

  • MEAP began January 2025
  • Last updated May 2026
  • Publication in Early 2027 (estimated)
  • ISBN 9781633435568
  • 450 pages (estimated)
  • printed in black & white

AI Agents are rapidly moving from side projects to an integral part of modern application architecture. Building AI Agents in .NET teaches you to develop effective, reliable, and enterprise-ready AI agents using Microsoft Agent Framework. You’ll learn how to design and deliver agents that are testable, observable, and deployable inside existing systems, scaling from local prototypes to production. Working with hands-on code, you’ll define agents, attach tools and memory providers, and orchestrate interactions, all integrated with dependency injection, logging, and middleware.

You’ll work to assemble Robby, a robot car assistant, evolving it from a minimal agent, then deepening our understanding of chat clients and model providers. From there, you’ll build complete agents from scratch, extend them with tools, memory, and Model Context Protocol, and harden them with middleware, observability, and evaluation. Finally, you’ll put Robby into multi-agent scenarios using sequential, concurrent, collaborative, and hierarchical patterns, finishing with custom workflows for long-running, stateful journeys.