Cursor vs Claude Code vs Codex vs Windsurf

Four tools, four marketing pages, all promising to write your code. Under the hood, how different are they really?

The same engine underneath

Here's the reassuring part: they all run the same core you've now seen — index the repo, loop through read-plan-edit-run, call tools, react to results. None of them invented a new kind of magic. What differs is where they live, how much they do on their own, and which model drives the loop.

Where each one lives

• —Cursor — an AI-first code editor (a fork of VS Code). The agent sits inside your editor, with your files and cursor right there.
• —Claude Code — a terminal-native agent. No special editor; it works in the shell alongside git and your tests.
• —Codex — OpenAI's coding agent, offered both in the terminal and as a cloud agent that works on tasks in the background.
• —Windsurf — another AI editor, known for leaning hard into automatic, multi-step edits across files.

The real axes to compare are interface (editor vs terminal vs cloud), autonomy (does it suggest one edit, or run for ten minutes on its own?), and the model underneath — which each tool lets you swap or pin. Pick the one whose home and autonomy match how you like to work, not the one with the loudest launch.

So which should you use?

There's no single winner — it depends on your workflow. Prefer staying in an editor? Cursor or Windsurf. Live in the terminal and love the command line? Claude Code or Codex. The honest answer is to try two on the same real task and keep the one that fits your hands. The loop underneath is the same either way.