I mostly mentioned Claude Code because it's what Mitchell first tried according to his post, and it's what I personally use. From what I hear Codex is pretty comparable; it has a lot of fans. There are definitely some differences and strengths and weaknesses of both the CLIs and the underlying LLMs that others who use more than one tool might want to weight in on, but they're all fairly comparable. (Although, we'll see how the new models released from Anthropic and OpenAI today stack up.) Codex and Gemini CLI are basically Claude Code clones with different LLMs behind them, after all.