🚀 OpenAI Releases Its Open-Source Coding AI Agent “Codex”

(And unveils o3 and o4-mini — Here's everything you need to know!)

In a major move, OpenAI has released Codex CLI, an open-source coding agent that runs directly in your terminal — plus two powerful new models, o3 and o4-mini.

Let’s break it down 👇

📌 o3 — Advanced Reasoning at Its Best

• 🧠 Advanced Analysis: Excels at complex, multi-faceted tasks.
• 📊 Visual Tasks: Understands and analyzes images, charts, and diagrams.
• 🔧 Agentic Tool Use: Decides autonomously when to use tools like web search and Python coding.

If you want deep thinking and multi-step execution, o3 is your new best friend.

📌 o4-mini — Cost-Efficient, Lightning-Fast Reasoning

• ⚡ Optimized for Speed and Cost: Ideal for fast, efficient operations.
• 🧮 Math & Coding Mastery: Sets new benchmarks in competitions like AIME.
• 🎨 Visual Capabilities: Strong performance across various visual tasks.

Perfect for everyday projects where you need performance without the heavy price tag.

📌 Codex CLI — My Favorite Part! 💻

Codex CLI is a lightweight agent that brings AI coding directly into your terminal. Here’s why it’s a game-changer:

• 🖥️ Local Operation: Works directly on your computer — no cloud dependency!
• 🔥 Model Support: Designed to maximize o3 and o4-mini's reasoning capabilities.
• 🖼️ Multimodal Reasoning: Accepts screenshots, charts, or even rough sketches as input.
• 🗂️ Local Code Access: Understands and interacts with your local files.

Imagine typing "Explain this codebase to me" and watching Codex scaffold, debug, and document everything — in seconds!

📌 Availability Highlights

• ✅ Available now for ChatGPT Plus, Pro, and Team users.
• 🎓 Enterprise and EDU users get access next week.
• 🙌 Free users will be able to try o4-mini soon through the "Think" feature.
• 📈 Rate limits remain unchanged!
• 🛠️ APIs for o3 and o4-mini are already available for developers.

📌 How to Get Started with Codex CLI

npm install -g @openai/codex
codex
        

Or run it with a prompt:

codex "Explain this codebase to me"
        

Want full auto-mode? Just add:

codex --approval-mode full-auto "Create the fanciest todo-list app"
        

It’s seriously THAT simple.

📌 Sources

🔗 Learn more: Introducing o3 and o4-mini

🔗 Codex CLI GitHub repo: https://github.com/openai/codex

🔥 Final Thoughts: OpenAI’s Codex CLI, combined with o3 and o4-mini, isn't just an upgrade — it’s the beginning of a new era for developers. Natural language coding, multimodal interaction, local-first autonomy — the future is here.

I'm genuinely excited to start using it daily. 🚀

Are you planning to try Codex CLI or explore o3/o4-mini? 👉 Let’s discuss in the comments!

#OpenAI #Codex #o3 #o4mini #AI #MachineLearning #Developers #Coding #Innovation #darshanamanikkuwadura Darshana Manikkuwadura (Dash)⚡️🇬🇧 🇱🇰⚡️ ✨