A Tour of Agents
A Tour of Agents is an interactive, in-browser course that builds an AI agent from scratch in about sixty lines of plain Python across nine lessons, showing what agent frameworks do under the hood.
A Tour of Agents teaches how an AI agent works by building one line by line, entirely in the browser using Pyodide, with nothing to install. Nine lessons take a learner from a function that calls a chat completions endpoint through tool calling, an agent loop, conversation history, structured state, persistent memory, input and output guardrails, and a self-scheduling task queue.
Each lesson shows the raw HTTP request and data structures behind the abstraction, and relates them to what frameworks such as LangChain, CrewAI, AutoGen and the OpenAI Agents SDK add on top. The course is explicitly not a library to install; the deliverable is understanding the primitives that agent frameworks wrap.
It is built with TypeScript and Pyodide (CPython compiled to WebAssembly) and released under the MIT license.