OpenAI Codex - The Definitive Course

April 2026 Edition - Updated to April 29, 2026

Definitive HTML course on OpenAI Codex, available in Italian and English.

---

Choose Your Language

• English README
• README Italiano

Course Files

• Italian course
• English course

What This Repository Contains

This repository intentionally contains only the public release files:

• README.md
• README.it.md
• README.en.md
• openai_codex_corso_definitivo_it.html
• openai_codex_corso_definitivo_en.html

No build step, local server, or extra dependency is required. Open the HTML file directly in a modern browser.

Current Model Positioning

The course reflects the April 29, 2026 model hierarchy used throughout the HTML files:

• GPT-5.5 for frontier Codex work, long-running tasks, architecture, Computer Use, and complex agentic coding.
• GPT-5.3-Codex as the specialized Codex/API model for agentic coding workflows.
• GPT-5.4, GPT-5.4-mini, and GPT-5.4-nano as cost/latency alternatives where appropriate.

Scope

The course covers Codex Desktop/App workflows, CLI, IDE usage, GitHub review, codex-action, AGENTS.md, sandbox and approval policies, MCP, skills, plugins, subagents, worktrees, enterprise governance, and master-level exercises.

Author

Christian Quintino De Luca

Email: INFO@RTHITALIA.COM