I Tried GPT-5 Codex and Here is Why You Must Too!

OpenAI has launched GPT-5 Codex, a variant of OpenAI’s newest AI mannequin GPT-5, specialised in agentic coding. It comes as a novel providing, offering real-time help to programmers with the power to autonomously carry out lengthy duties. GPT-5 Codex will repair pre-existing bugs earlier than deployment, full exceptionally sophisticated refactoring, and combine with something out of your cloud atmosphere and IDE to command line terminals, GitHub, and ChatGPT straight.

Codex CLI brings these capabilities to your terminal and permits studying, rewriting, and executing code domestically. You may request a particular function, debug, or ask for a proof with out breaking out of the shell, and hold full connectivity together with your ChatGPT account. Right here, we are going to consider the efficiency of Codex CLI to see the way it handles actual programming duties, particularly net growth and knowledge evaluation.

What’s Codex CLI?

The brand new GPT-5-based Codex CLI is an open-source command-line device forked from OpenAI’s unique Codex CLI. It now helps a number of AI suppliers. It allows builders to work together with giant language fashions within the terminal for duties like code technology, refactoring, script clarification, and lots of extra.

Codex CLI acts as a wise terminal accomplice for coding. It listens to your requests and writes code. Codex CLI has entry to your shell and file system. In case you’re in search of detailed walkthroughs, try the guides on codex CLI from OpenAI:

https://openai.com/index/introducing-upgrades-to-codex

Set up

Earlier than continuing with the set up, make sure that the system necessities are happy.

System Necessities for Codex CLI

• Working System: macOS 12+, Ubuntu 20.04+, Home windows 11 (by way of WSL2)
• Node.js Model: 22 or newer (LTS advisable). You may set up Node.js by following the directions on its official web page: https://nodejs.org/
• npm: Required (comes with Node.js)
• Git: Non-compulsory however advisable
• RAM: 4 GB minimal, 8 GB advisable
• Web: Required
• Authentication: OpenAI API Key

Set up Steps for Codex CLI

1. Test Node.js model:

node --version #Make sure that it's model 22 or greater.

2. Set up Codex CLI globally, or utilizing pnpm:

pnpm add -g @openai/codex

3. After logging in together with your GPT-Plus or Professional credentials, you will note the next display.

4. Add this line to your shell config file (e.g., ~/.bashrc, ~/.zshrc) for persistence.

5. Run Codex CLI:

codex

6. Or move a immediate straight:

codex “clarify this codebase to me”

Issues to Maintain in Thoughts

• Node.js and npm (Node Bundle Supervisor) should be put in and accessible in your system PATH.
• For Codex CLI, Node.js 22+ is required, whereas Gemini CLI works with Node.js 18+.
• Each require authentication by way of API keys or account login for full performance.
• On Home windows, Codex CLI is finest run by way of WSL2 for full compatibility.
• Keep in mind, once you need to use your CLI for a sure undertaking, ensure you have the present working listing set to the folder path the place your undertaking exists.

Operating our CLI Cases

Let’s proceed to check the codex with GPT-5 on 3 duties

• Constructing a sport on a neighborhood host
• Constructing a Each day calorie-tracing software
• Constructing a Sentimental Evaluation Mannequin Workflow

If all of the set up steps are full and the system necessities are met, we will begin with the checks.

Activity 1 – Constructing a sport on a neighborhood host

Purpose: Construct a 2D arcade shooter with enemies and scoring.

Immediate:

“Create a easy 2D house shooter sport utilizing JavaScript and HTML5 canvas (or Python Pygame if most well-liked). The sport ought to show a spaceship managed by the participant with keyboard arrow keys for motion and the spacebar for capturing. Enemies ought to spawn on the prime and transfer downward at random intervals. Implement collision detection so bullets destroy enemies and enhance the rating. Add a primary game-over situation if enemies collide with the participant’s ship. Use pixel-art fashion graphics and guarantee easy animations.”

It’s evident that Codex efficiently produced an virtually totally outlined 2D house shooter, being very clear and exact in its output. The implementation included participant controls, enemy spawning, collision detection, and scoring, all organized in a means that was simple to observe. Nearly each time, it ran in beneath one second with solely minor changes, which was a pleasing shock.

Output:

The very easy design, pixel-art graphics, and responsive animations supplied a refined really feel, even though it was a easy sport. The USP right here was Codex’s potential to principally translate a natural-language immediate right into a functioning interactive prototype. The sport-over logic, rating monitoring, and even text-displaying messages had been all useful as nicely, demonstrating Codex’s talents in each logic and presentation.

Activity 2: Constructing a Each day calorie-tracing software

Purpose: Construct an interactive dashboard with charts and consumer enter.

Immediate:

“Develop a health tracker dashboard utilizing HTML, CSS, JavaScript, and a charting library (like Chart.js). Enable the consumer to log each day steps, energy burned, and hours slept. Show this knowledge in real-time on dynamic charts (bar chart for steps, line chart for energy, pie chart for sleep distribution). Add a weekly abstract part that calculates averages and highlights one of the best/worst day. Embody a easy native storage mechanism so consumer knowledge persists throughout web page refreshes. Type the dashboard with a clear, fashionable UI.”

Output:

GPT-5 Codex supplied probably the most sensible and feature-rich implementation. It built-in Chart.js easily, with responsive bar, line, and pie charts updating in actual time. The weekly abstract part calculated averages precisely, highlighting one of the best and worst days with readability. Moreover, Codex dealt with native storage nicely, making certain persistence throughout periods, and styled the dashboard with a clear, fashionable interface.

Activity 3: Constructing a Sentimental Evaluation Mannequin Workflow

Purpose: Analyze textual content knowledge for insights.

Immediate:

“Carry out sentiment evaluation on a dataset. Implement this in a Jupyter Pocket book. Begin by cleansing the textual content (take away stopwords, punctuation, and apply tokenization). Use a pre-trained sentiment evaluation mannequin (e.g., from Hugging Face Transformers or TextBlob). Evaluate mannequin predictions with precise scores and calculate accuracy. Visualize the distribution of constructive, impartial, and destructive sentiments utilizing charts. Finish with at the least three insights about how buyer scores align (or misalign) with the sentiment evaluation mannequin.”

Output:

GPT-5 Codex delivered a transparent and structured workflow for sentiment evaluation. It carried out textual content cleansing, tokenization, and mannequin integration with minimal friction, producing dependable outcomes total. The comparability of predictions with precise scores labored nicely, and the accuracy calculation was easy. Aside from a small error in a single print assertion, every thing executed easily, together with saving sentiment distribution charts for insights.

You could find the entire code kind right here and obtain the dataset from Kaggle.

We not too long ago in contrast Codex with Gemini and Claude Code (learn the total comparability right here). On the time, we discovered Claude Code to be one of the best throughout all duties. Nevertheless, the brand new GPT-5-based Codex brings vital enhancements with respect to its earlier model. Within the subsequent part, we’ll evaluate the general efficiency of the brand new GPT-5-Codex in these regards.

Total Evaluation

In my earlier weblog, whereas accessing and evaluating Codex CLI, Gemini CLI, and Claude Code, every exhibited differing strengths. Codex was nice at producing quick and iterative code. Gemini was extra helpful with energetic search outcomes and operating instructions. Claude produced depth with nice documentation and construction. Every device can simply be used for debugging or intervention. Although they need to be checked by a human previous to deployment.

GPT-5 Codex is a exceptional enchancment of the Codex line. As a lot because it retains the velocity and readability of Codex, it now contains agentic autonomy to deal with bug fixes, refactoring, visualization, and run workflow with no /little intervention. In contrast to Gemini’s use-case framework and Claude’s construction and depth, or velocity of navigation, GPT-5 Codex turns into a mix of each ends: producing good, clear, dependable, and production-ready options digitally at an alarming tempo as coded, making it one of the best device of the three.

Conclusion

GPT-5 Codex with Codex CLI demonstrates how AI can function a dependable accomplice in coding by changing pure language prompts into useful, production-ready code. From participating interactive video games to polished dashboards and sentiment evaluation workflows, it produced polished work with solely minimal edits wanted, demonstrating its versatility in growth purposes.

Along with automation, Codex enhances developer productiveness by simply integrating into IDEs, terminals, and cloud environments. The power to help meaningfully in real-time with debugging, refactoring, and automation makes it each a useful and related fashionable programming device. Whereas a few of its outputs might proceed to want minor revisions, Codex exemplifies the way forward for agentic coding for programmers to raise their working, high-potential merchandise.