What it does
This is a set of example programs that teach how AI agents are built, without using ready-made frameworks (pre-built toolkits). An AI agent here means a language model plus tools, memory and a way of reasoning through problems.
The lessons run in order, from loading a local AI model and asking it simple questions, to giving it tools it can use, letting it remember facts between sessions, and having it reason step by step. Later lessons cover planning methods, error handling and choosing which tools to offer the model.
Each lesson comes with the working code, a line-by-line explanation and a page on the bigger ideas. The examples use AI models that run on your own computer, with one optional lesson on calling a paid online model. A companion website explains the concepts, and a Python version is also available.
Who it's for
Programmers who want to understand what happens inside AI agents before using popular agent frameworks.
Can I use it without coding?
Developers only. You need to install Node.js, download model files and run JavaScript examples from the command line. New to this? Start here.
Can I run it?
- Cost
- FreeNothing to pay or sign up for.
- Computer
- An ordinary computer is fine
- Privacy
- Runs on your own device: your data stays with you
- API key
- Not needed
Try it
Using Claude Code, Cursor or another AI coding assistant? Paste the prompt and it will walk you through the setup.New to this?
Before you install
- Only download from the official GitHub page. Copies with similar names exist for many popular projects.
- Plain-AyI is an independent guide and doesn't host or review the software it lists. Please check each project's official page before installing.
- License (MIT): Very permissive: free to use, change and share, including for business.
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