Building an AI Coding Agent from Scratch with Claude Agent SDK

Building an AI Coding Agent from Scratch with Claude Agent SDK You've been using Claude as a chatbot — paste code, get a reply, paste again. That works. But there's a different mode entirely: give Claude a set of tools and a goal, and let it figure out the steps itself. That's what an agent is. Not a smarter autocomplete — a loop that reads files, runs checks, makes decisions, and calls your code until the job is done. In this article, I'll walk through building a TypeScript code review agent us