AI Agent Architectures

I dug into the source code of 8 open-source AI agent frameworks to understand how they actually work. This is what I found -- and what you can steal for your own agents.

Each framework gets 30+ pages of annotated source code and architecture diagrams -- covering event loops, memory, tools, security, and LLM integration. The Comparison page puts all eight side by side. The Build Your Own guide turns the patterns into concrete advice for building your own.

Who is this for?

Software engineers who want to go beyond β€œcall the API” and understand what's actually happening inside these systems -- event loops, memory architectures, tool sandboxing, context management, and security models.

How to use this site

  • Start with the Comparison for a bird's-eye view
  • Pick a framework page to read annotated source code
  • Check Architecture Patterns for design themes that show up across frameworks
  • Use Build Your Own when you're ready to start coding

The Frameworks