What is codex-orange-book?

This repository contains a free downloadable book called "OpenAI Codex: The Complete Guide," published in both English and Chinese. It is part of an "Orange Book" series of practical guides for AI-powered software development, written by an author who describes building multiple products entirely using AI tools without writing code manually. The book covers OpenAI Codex, an AI coding assistant, across all the different ways it can be used: as a command-line tool, a desktop application, a cloud-based environment, an IDE extension, and a Chrome browser extension, plus its mobile companion. It is structured to take readers from first installation through to building and shipping real products. Key topics include Codex's auto-review system (which handles most routine actions without interrupting you), the AGENTS.md configuration file for controlling agent behavior, integration with other tools and services through skills and automation features, and an honest comparison of when Codex versus Claude Code is the better tool for a given situation. The author also calls out known limitations and risks, including specific reports of data loss from certain Codex modes. The book is available as PDF, EPUB, and single-file HTML, downloadable directly from the repository. Version 2.0.1, the current version at the time this README was written, reflects major updates including the arrival of GPT-5.5 as the default model. The license allows free sharing and adaptation for non-commercial purposes with attribution.