Principles of Building AI Agents book [pdf]
Hi, I’m Sam, the cofounder/CEO of Mastra, the Typescript agent framework. I wrote a book on building agents and wanted to share it with HN. The book is called Principles of Building AI Agents. Right now it has 34 chapters and 148 pages covering LLMs, prompting, agents, workflows, RAG, evals, multi-agent, tracing, deployment, MCP, tool use, and a few other topics. The backstory here is that last October when we started working on Mastra we knew very little about AI engineering, and had to learn as we were building. In January, we started going to local AI meetups. We met a lot of people…
Principles of Building AI Agents book [pdf] launched on August 6, 2025 with 5 votes and more than 75% of that year's launches. The site was not reachable when checked in September 2026.
What it does
In the maker’s words, at launch
Hi, I’m Sam, the cofounder/CEO of Mastra, the Typescript agent framework. I wrote a book on building agents and wanted to share it with HN. The book is called Principles of Building AI Agents. Right now it has 34 chapters and 148 pages covering LLMs, prompting, agents, workflows, RAG, evals, multi-agent…
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