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Codex

Codex
: How to use it, features, and the business problems it solves

# Code Generation# AI Agent

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Try Codex

What is Codex?

Codex (ChatGPT's Codex) is an AI coding agent for software engineering offered by OpenAI. You can use it from ChatGPT, an IDE extension, the terminal (Codex CLI), and a macOS app, all linked through your ChatGPT account. Powered by frontier coding models, it completes work end to end from PRs to complex refactoring and migrations, runs in parallel across worktrees and the cloud, and supports skill learning, always-on background work, and code review. It's available on ChatGPT's paid plans (Plus/Pro/Business/Enterprise) plus the API, and the CLI is open source.

Business problems it solves

About "Codex"

What is Codex

Codex (ChatGPT's Codex) is an AI coding agent for software engineering, offered by OpenAI. You can use it from within ChatGPT, as well as through an editor extension, the terminal (Codex CLI), and a macOS app — all linked through your ChatGPT account. Powered by OpenAI's frontier coding models, it completes tasks end to end, from everyday pull requests to complex refactoring and migrations.

An agent you hand tasks to, not just autocomplete

Codex is positioned not as word completion but as something you hand an entire task to and let carry it through implementation, testing, and review. With built-in worktrees and a cloud environment, it can work on multiple projects in parallel, and if you teach it your team's standards and workflows through skills, it delivers consistent results with minimal supervision. It's also well suited to always-on background work like issue triage and CI/CD.

How to use it

  1. Enable it in ChatGPT

    You can use Codex from the ChatGPT app. A macOS app is also available to download.

  2. Install the editor / CLI

    Install the Codex IDE extension, or set up the CLI with npm i -g @openai/codex.

  3. Assign a task

    Request tasks such as implementation, fixes, refactoring, or migrations in natural language.

  4. Run in parallel and review

    Run multiple tasks in parallel across worktrees and the cloud, and review the generated changes and PRs.

  5. Automate

    Schedule work like triage and CI/CD to run in the background.

Features

01Execute

See tasks through to the end.

  • End-to-end implementation — feature additions, refactoring, migrations
  • Frontier models — OpenAI's latest coding models
  • Skills — learn your team's standards and ways of working

02Parallel and always-on

Weeks of work in days.

  • Multi-agent — parallel processing across worktrees and the cloud
  • Background work — triage, alert monitoring, CI/CD

03Quality and a unified environment

The same Codex everywhere.

  • Code review — catch bugs to raise release confidence
  • Unified agent — connect ChatGPT, editor, and terminal

Pricing

Codex is offered as part of ChatGPT. It's available on ChatGPT's paid plans (Plus / Pro / Business / Enterprise) and can also be used via the API. The Codex CLI is open source, with costs based on your model usage (as of August 2026).

Offering
Included in ChatGPT's paid plans (Plus/Pro/Business/Enterprise) + API
CLI
Open source. Usage-based billing for model use. Check each ChatGPT plan / the official site for specific limits and pricing

How it differs from other AI coding agents

Codex stands out for bundling the editor, terminal, and cloud around ChatGPT under a single account. It suits those who don't want to be tied to a specific editor and prefer to keep everything within the ChatGPT ecosystem.

CodexClaude CodeCursor
ProviderOpenAI (ChatGPT)AnthropicAnysphere
FormChatGPT + IDE extension + CLI + cloudTerminal-centric agentA dedicated editor built for AI
StrengthChatGPT integration, parallel processing, always-onDeep reasoning with ClaudeRefined editor experience

If you want to use Claude in the terminal, Claude Code is a good point of comparison; for a dedicated-editor experience, Cursor; and for GitHub integration, GitHub Copilot.

The information on this page is based on what was published on the official site as of August 2026. Please check the official site for the latest specifications and pricing.

Try Codex

Frequently compared services

Devin

Devin

An autonomous AI software engineer from the startup Cognition (a coding agent). From a natural-language instruction it autonomously plans, implements, tests, and opens a Pull Request in its own environment, supporting multiple repos and parallel sessions. The current Devin 2 generation offers Core from $20/mo (metered ACU), Team $500/mo, and Enterprise, and integrates with GitHub/Slack/IDE and MCP/API.

# Code Generation# AI Agent# Automation & Labor Reduction# Productivity Improvement
Cursor

Cursor

Cursor is an AI coding agent (AI code editor) from Anysphere. A VS Code-based desktop app (macOS / Windows / Linux), it takes natural-language instructions and has an agent that understands your codebase handle planning, implementation, and fixes. You can choose its in-house Composer model, Grok, or frontier models from various providers, and it supports running multiple tasks in parallel, cloud agents, agentic code review by Bugbot, MCP, skills, and hooks, and privacy mode. A Cursor CLI and iOS app are also available. Pricing includes Hobby free, Pro $20, Pro+ $60, Ultra $200, and Teams $40 (per user, per month), among others.

# Code Generation# AI Model Development & Management# AI Agent# Operational Efficiency# Japanese Supported
Windsurf（現Devin Desktop）

Windsurf（現Devin Desktop）

Windsurf (formerly Codeium) was an AI coding tool known as an AI-native code editor, but in 2025 it was integrated into Cognition, the company behind Devin, and is now offered as "Devin Desktop" (windsurf.com redirects to devin.ai/desktop). Devin Desktop is a desktop app that lets you plan, delegate, and review a group of local and cloud AI agents in a single screen (a Running/Waiting for review/Done session board) without leaving the editor. It is distributed for macOS and other platforms.

# AI Agent# No-Code Automation# Notification & Task Integration# Operational Efficiency
Cline

Cline

Cline is an open-source AI coding agent that runs inside the editor and terminal you already use (built by Cline Bot Inc., Apache 2.0). You can use the same agent from a VS Code extension, JetBrains, a CLI, or an SDK, and with Plan/Act it separates planning from execution so you approve as it goes, autonomously handling multi-file edits and command execution. It supports every provider — Claude, GPT, Gemini, local models and more — and with bring your own key there is no vendor lock-in. The extension and CLI are open source and free for individuals (the only cost is usage-based model inference). Used by more than 8 million developers, with 66,000 GitHub stars.

# Code Generation# AI Model Development & Management# API & SDK# AI Agent
GitHub Copilot

GitHub Copilot

GitHub Copilot is an AI coding assistance service provided by GitHub (a Microsoft subsidiary). In addition to code completion, it includes an agent mode that implements autonomously, a cloud agent that works in the cloud, automatic PR review, and the Copilot CLI. It can be used in VS Code, JetBrains, GitHub, the terminal, and more, and you can choose from major models such as Claude, GPT, and Gemini. For individuals there is the free Free plan, Pro $10, Pro+ $39, and Max $100; for businesses there are Business $19 and Enterprise $39 (per user/month, on a GitHub AI credit system).

# Code Generation# AI Model Development & Management# API & SDK# AI Agent
v0

v0

v0 is an AI full-stack web app builder from Vercel. Just describe what you want in plain language, and it generates a working app in minutes and publishes it live in seconds. Agentic by default, it autonomously handles planning, task creation, and even database connections, and it supports visual editing in Design mode, GitHub integration, one-click deployment to Vercel, and an iOS app. You can choose from the v0 Mini, Pro, Max, and Max Fast models, and pricing is credit-based with tiers such as Free $0, Plus $30, and Business $100 (per user, per month).

# Code Generation# No-Code Automation
Greptile

Greptile

An AI code-review tool where AI agents automatically review GitHub/GitLab pull requests with full-codebase context. It catches multi-file bugs, anti-patterns, and security risks, and can generate tests and hand off fixes to coding agents.

# Automation & Labor Reduction# Code Generation# Productivity Improvement
CodeRabbit

CodeRabbit

An AI code review platform that connects to GitHub/GitLab/Azure DevOps/Bitbucket and auto-reviews pull requests. Beyond summaries, bug/security detection, and one-click fixes, it offers free IDE reviews (VS Code/Cursor) plus CLI and AI-agent loops. Used by 17,000 companies. OSS free / Pro from $24/seat.

# Code Generation# Automation & Labor Reduction# Productivity Improvement
Kilo Code

Kilo Code

Kilo Code is an MIT-licensed open-source AI coding agent that runs the same way in VS Code, JetBrains, the CLI, and the cloud. You switch between purpose-built agents — Code, Plan, Ask, Debug, and Review — to generate code, refactor, chase bugs, and review changes. It supports 500+ models with mid-task switching, and charges no markup on AI inference: you pay the provider's rate. You can bring your own API keys or run local models with Ollama. Platform access is free for individuals and $15 per user per month for Teams. Anaconda acquired the company in July 2026, and Kilo Code now has more than 3 million users.

# Code Generation# AI Agent# API & SDK# Productivity Improvement# Japanese Supported

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