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IDEOpenAI

OpenAI Codex CLI

OpenAI's open-source coding agent for the terminal.

Categories
IDEAgent
Pricing
FREEMIUM
Source
Open core
Hosting
Local
Platforms
CLImacOSLinuxWindows
Models
Single model (proprietary)
Verified
Jun 7, 2026

A lightweight, open-source coding agent that runs locally in your terminal, reading your repository, editing files, and running commands in a conversational loop you review in real time. Built in Rust for speed, it supports Model Context Protocol tools, subagents for parallel tasks, and switching between GPT models. Sign in with a ChatGPT plan (Plus, Pro, Business, Edu, or Enterprise) or use an OpenAI API key.

Capabilities 5

What it actually does — grouped by capability family.

  • Autonomous coding agent (primary capability)
  • Terminal / CLI agent (primary capability)
  • Code generation (secondary capability)
  • Code review (secondary capability)
  • MCP server (secondary capability)

Pros & cons

  • Runs locally in your terminal
  • Fast Rust implementation
  • MCP tools and parallel subagents
  • Reviewable conversational edit loop
  • Best with OpenAI/GPT models
  • Terminal-only, no full IDE
  • Newer than rival CLIs

Tags

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Open OpenAI Codex CLI