Build an AI Coding Agent from Scratch in Python (Complete Tutorial)

Sat, 07 Mar 2026 18:00:00 +0800

Every AI coding tool — Claude Code, Cursor, Copilot — runs on the same core architecture. In this tutorial, you will build that architecture yourself: a terminal AI coding agent in Python, from zero to a working 250-line tool that reads files, writes code, runs commands, and makes autonomous multi-step decisions.

No frameworks. No abstractions. Just Python and a clear understanding of how AI agents actually work.

Build Your Own Claude Code from Scratch in Python (250 Lines)

Tue, 24 Feb 2026 10:00:00 +0800

You’ve probably used Claude Code — or at least heard the hype. It reads your codebase, writes files, runs tests, and fixes bugs, all from a terminal prompt. It feels like magic.

But here’s the thing: the core architecture behind it is surprisingly simple. Simple enough that you can rebuild it from scratch in an afternoon with Python and about 250 lines of code.

Agentic Loop on Bruce on AI Engineering

Build an AI Coding Agent from Scratch in Python (Complete Tutorial)

Build Your Own Claude Code from Scratch in Python (250 Lines)