cli-harness is the companion repository for a 14-day series about building a mini coding agent harness from scratch.

The project starts from a TypeScript/Node CLI and gradually introduces the core pieces behind Cursor/Codex-style products: context building, tool runtime, agent loop, transcript logging, patch editing, approval, sandboxing, and project rules.

The goal is not to clone a full IDE agent. The goal is to make the harness layer visible, small, and understandable.