VerlumoAIAI coding agents that write, test, and review code across your whole codebase.
View detailsCodex CLI
OpenAI's open-source terminal agent that brings Codex coding help to the command line.
Codex CLI is OpenAI's open-source terminal agent that brings Codex coding help to the command line. It can read your project, write and edit code, run tests, and explain what it is doing, all from a terminal session. It is the command-line counterpart to the Codex agent in ChatGPT.
Key Features
- Open-source terminal coding agent
- Reads, writes, and edits project code
- Runs tests and commands for you
- Approval modes control agent autonomy
- Works with OpenAI models via API
- Free to install and use
Pricing
| Plan | Price | Details |
|---|---|---|
| Free | $0 | Free and open source; model usage is billed through your OpenAI API account. |
Prices as listed in 2026 research. Always check the official site for the latest price — plans change. Free plan: Yes — it has a free plan.
Best for: developers who want OpenAI's coding agent in the terminal, for free.
Popular with: Developers, Students
Popular with: Developers, Students
How it works
The tool is free and open source, but the model usage behind it is billed through your OpenAI API account, so the cost depends on how much you use it. It supports different models and approval modes, letting you choose how much autonomy the agent has over your files.
Codex CLI is best for developers who live in the terminal and want an agentic coding helper without a subscription. It competes with Claude Code and Gemini CLI on similar ground, so the best choice depends on which models you prefer. If you want a graphical experience, the Codex agent in ChatGPT or an IDE extension is a better fit.
Pros and Cons
✓ Pros
- Free and open source
- Agentic coding in the terminal
- You control how much autonomy it has
- Backed by OpenAI's Codex models
✗ Cons
- Usage is billed through the OpenAI API, so costs vary
- Terminal-only; no graphical interface
- Requires an OpenAI API key and some setup
Frequently Asked Questions
Is Codex CLI free?
Yes — Codex CLI has a free plan. Free open source; API usage billed separately
What is Codex CLI best for?
developers who want OpenAI's coding agent in the terminal, for free.
What kind of tool is Codex CLI?
Codex CLI is a Coding Assistants tool on VerlumoAI.
Related Tools
AI code reviewer that refactors Python and reviews every pull request.
View detailsVisual full-stack builder that turns designs into real, ownable code.
View detailsLast reviewed: November 2026