tools
OpenAI Codex CLI Review 2026 — Open-Source Terminal Coding Agent
OpenAI Codex CLI is an open-source terminal agent running GPT-5.4 with MCP support, cloud task execution, and sandboxed security. Requires ChatGPT Plus.
Codex CLI is a command-line coding agent that runs on a user's computer. It can work within a local codebase, execute commands, apply changes, review code, and manage tasks from the terminal.
Developers can install it on macOS, Windows, or Linux using standalone installers, npm, or Homebrew. It is available under the Apache-2.0 license and can use a ChatGPT plan or an OpenAI API key; API usage may cost extra.
Features
- Runs a coding agent locally from the terminal
- Reads and modifies files in a local codebase
- Executes commands and works within project directories
- Runs non-interactive tasks with the exec command
- Performs non-interactive code reviews
- Supports MCP servers and plugins
- Provides sandboxed command execution
- Licensed under Apache-2.0
Use cases
- Explain an unfamiliar codebase
- Implement a feature in an existing project
- Fix bugs and apply changes to a working tree
- Run automated code reviews from the command line
- Manage MCP tools and coding workflows
- Test changes in a local development environment