Understand Pi in six short reads
Pi is a minimal, self-extensible coding agent that lives in your terminal. This little book skips the wall of text and walks you through what actually matters — the loop, the tools, the memory, the session tree, and how to reshape it all — in a friendly, plain-spoken way. Written from the real project sources, not press releases.
Chapters 1–4 explain how Pi works; chapters 5–6 cover the features that make it fun to live with.
The six chapters
Meet Pi
What Pi is, why it's interesting, and how to get it running in about a minute.
The Loop
The heart of every agent: think, act, observe, repeat. How Pi knows when to stop — and how you can interrupt.
Tools
Four default tools, a five-step safety pipeline, and Pi's honest answer to the permissions question.
Memory
How Pi feeds a forgetful model everything it needs, trims what it doesn't, and compresses the past when the window fills up.
Time Travel
Pi saves every conversation as a branching tree in a plain text file. Rewinding, forking, and exploring alternate timelines are built in.
Make It Yours
Pi's endgame isn't a product you use — it's a platform you reshape. Extensions, skills, packages, and embedding Pi in your own code.