In January, Sam Altman, the CEO of OpenAI, famously told us that 2025 would be the “year of agents.”

In late February, Sam Bhagwat published the first version of his book Principles of Building AI Agents to help educate developers. Sam, is a veteran of web development and long time part of our community,

The book has become the go-to guide for engineers building with AI — and their product managers and CEOs. One founder from the famous Y Combinator startup incubator even called it "the most popular book in San Francisco".

Now it is out in the 2nd edition with new sections on MCP, image generation, voice, Agent 2 Agent, and much more. As Sam notes in the foreword, two months is a very short time to write an updated edition of any book, but AI is masterful at time dilation.