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Coding assistants

Codex CLI

A coding helper from OpenAI that runs in your computer's terminal and works on your code with you.

Widely used

What it does

Codex CLI is a coding agent from OpenAI. An agent is an AI helper that can carry out tasks, not just answer questions. It runs in the terminal, the text window where you type commands, on your own computer.

You can sign in with a ChatGPT account and use it as part of a paid ChatGPT plan such as Plus, Pro, Business, Edu or Enterprise. You can also use it with an API key (a password-like code from OpenAI), though the README says this needs extra setup.

The README also mentions other ways to use Codex: inside code editors like VS Code, Cursor or Windsurf, as a desktop app, or as a separate cloud-based version called Codex Web.

Who it's for

Programmers and people learning to code who want an AI helper that works alongside them in the terminal. It suits people who already have a ChatGPT plan or an OpenAI API key.

Can I use it without coding?

With some setup. You install it by pasting one command or using a package manager, then use it from the terminal. New to this? Start here.

Can I run it?

Cost
Free, but needs an AI accountThe software is free, but it uses an online AI service (like OpenAI or Anthropic), which usually charges for use.
Runs on
Mac, Windows, Linux
Computer
An ordinary computer is fine
Privacy
Sends what you give it to an online service
API key
Not needed

Try it

  1. Run codex in your terminal.
  2. Choose "Sign in with ChatGPT" and log in with your ChatGPT plan.
Official download page

Before you download

Plain-AyI is an independent guide: we link to each project's official pages, but we don't host, review or endorse the software, and we can't accept responsibility for how it works on your device. Please download and install at your own discretion.

Using Claude Code, Cursor or another AI coding assistant? Paste the prompt and it will walk you through the setup.New to this?

Before you install

  • Only download from the official GitHub page or the official download page above. Copies with similar names exist for many popular projects.
  • Plain-AyI is an independent guide and doesn't host or review the software it lists. Please check each project's official page before installing.
  • License (Apache-2.0): Permissive: free to use, change and share, including for business.
  • What you type or upload is sent to an online service. Avoid sharing private or sensitive information.
  • More on staying safe

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