Codex CLI
OpenAI's open-source terminal coding agent built in Rust. Runs locally, reads your repo, edits files, and executes commands. Powered by o3 and o4-mini models.
Codex CLI is OpenAI's open-source coding agent that runs directly in your terminal. Built in Rust for speed, it launches into a full-screen terminal UI where it reads your repository, makes edits, and runs commands as you iterate together. It brings the power of o3 and o4-mini into your local workflow with a conversational interface where you review every action in real time. Install via npm or Homebrew, authenticate with your ChatGPT account or API key, and you are coding. The codex-mini model is optimized specifically for low-latency code Q&A and editing. It is included with ChatGPT Plus, Pro, Business, Edu, and Enterprise plans at no additional cost. For developers who want OpenAI's models in a local terminal workflow rather than a browser, this is the tool.
Similar Tools
Gemini CLI
Google's open-source coding CLI. Free tier with Gemini 2.5 Pro. Supports tool use, file editing, shell commands. 1M token context window.
Aider
Open-source AI pair programming in your terminal. Works with any LLM - Claude, GPT, Gemini, local models. Git-aware editing with automatic commits.
Kimi Code
Open-source terminal coding agent from Moonshot AI. Powered by Kimi K2.5 (1T params, 32B active). 256K context window. Agent Swarm runs up to 100 parallel sub-agents.
Claude Code
Anthropic's agentic coding CLI. Runs in your terminal, edits files autonomously, spawns sub-agents, and maintains memory across sessions. Powered by Claude Opus 4.
Get started with Codex CLI
OpenAI's open-source terminal coding agent built in Rust. Runs locally, reads your repo, edits files, and executes commands. Powered by o3 and o4-mini models.
Try Codex CLIGet weekly tool reviews
Honest takes on AI dev tools, frameworks, and infrastructure - delivered to your inbox.
Subscribe FreeMore AI Coding Tools
Claude Code
Anthropic's agentic coding CLI. Runs in your terminal, edits files autonomously, spawns sub-agents, and maintains memory across sessions. Powered by Claude Opus 4.
Cursor
AI-native code editor forked from VS Code. Composer mode rewrites multiple files at once. Tab autocomplete predicts your next edit. Pro plan is $20/mo.
OpenAI Codex
OpenAI's cloud coding agent. Runs in a sandboxed container, reads your repo, executes tasks, and submits PRs. Uses GPT-5.3 (codex model). Available in ChatGPT.
Related Guides
Getting Started with DevDigest CLI
Install the dd CLI and scaffold your first AI-powered app in under a minute.
Getting StartedRun AI Models Locally with Ollama and LM Studio
Install Ollama and LM Studio, pull your first model, and run AI locally for coding, chat, and automation - with zero cloud dependency.
Getting StartedClaude Code Setup Guide
Configure Claude Code for maximum productivity -- CLAUDE.md, sub-agents, MCP servers, and autonomous workflows.
AI AgentsRelated Posts

OpenAI's GPT 5.4 in 10 Minutes
State-of-the-art computer use, steerable thinking you can redirect mid-response, and a million tokens of context. GPT 5....

Anthropic vs OpenAI: Developer Experience Compared
Two platforms, two philosophies. Here is how Anthropic and OpenAI compare on APIs, SDKs, documentation, pricing, and the...

Cursor 2.0 & Composer: The Fastest AI Coding Model
Cursor just dropped their first in-house model. Composer is 4x faster than similar models and completes most coding task...
