OpenAI Codex CLI vs TUI-use

OpenAI's Codex CLI is a lightweight, open-source coding agent that runs directly in your terminal. Unlike the deprecated Codex API, this is a fully agentic tool: describe what you want in plain English, and Codex figures out which files to modify, what commands to run, and how to verify the result. Built in Rust for performance, it taps OpenAI's most capable reasoning models — o3 and o4-mini — to tackle complex, multi-step coding tasks. The tool has accumulated 67,000+ GitHub stars and over 400 contributors, making it one of the fastest-growing open-source developer tools in recent memory. It installs via npm or Homebrew, integrates into existing terminal workflows, and supports sandboxed execution mode where it can read, change, and run code within a specified directory. ChatGPT Plus, Pro, Business, and Enterprise subscribers get Codex access bundled into their plans. Codex CLI directly competes with Claude Code and Gemini CLI in the terminal AI agent space. Its differentiator is reasoning depth — the o3 and o4-mini models handle algorithmic complexity and multi-file refactors better than most alternatives. But the paid API requirement (beyond what's bundled in ChatGPT plans) is a real consideration vs. Gemini CLI's free tier.

TUI-use is an open-source library that gives AI agents the ability to interact with traditional interactive terminal (TUI) applications — think vim, htop, ssh sessions, database CLIs, and legacy text-based UIs that were never designed for programmatic control. Instead of requiring a GUI or a REST API, TUI-use interprets terminal output as structured state and sends synthetic keystrokes back, enabling agents to "see" and "drive" any TUI application as if they were a human at a keyboard. The project was born from a real pain point: AI coding agents can call bash commands and write files, but they fail badly the moment a tool opens an interactive prompt waiting for user input. TUI-use solves this by building a state machine layer over PTY (pseudo-terminal) interfaces, letting agents read the current screen buffer, detect interactive prompts, and respond intelligently. It ships with adapters for common TUI patterns and a clean API that works with any LLM tool-use framework. The Show HN post attracted genuine interest from the ops and DevOps community — many existing workflows depend on tools that expose only an interactive terminal interface. TUI-use fills a real gap in the "AI agents that control computers" space by handling the long tail of CLI programs that have no API, no GUI, and no intention of ever getting one.