Codex vs Cursor: what still separates them

Side by side

Both crossed into the other’s lane

Comparison articles for this pair are mostly a year out of date, and the two stalest claims are that Cursor cannot run without a GUI and that Codex cannot help you while you are reading code. Neither is true now.

• Cursor has a command-line agent. The binary is agent, it takes a prompt with -p, and Cursor documents print mode explicitly for scripts and CI pipelines.
• Codex has an IDE extension that runs beside your editor, including inside Cursor, Windsurf, VS Code, Xcode and JetBrains. It is the same agent with your open files and your selection.
• Both have a cloud surface. Codex web runs a task in an OpenAI-managed container against a clone of your repository; Cursor runs cloud agents on paid plans.
• Both parallelise with git worktrees. Cursor built it into the product; Codex expects you to create the worktree, or to hand the task to the cloud.

# Codex CLI. A Rust binary, so Node is not required.
curl -fsSL https://chatgpt.com/codex/install.sh | sh
codex          # then sign in with your ChatGPT account

# Cursor CLI. The binary is called agent, not cursor.
curl https://cursor.com/install -fsS | bash
agent -p "explain how sessions are authenticated" --output-format text

The sandbox is the difference that did not close

Codex confines itself with facilities provided by the operating system, outside the agent loop. That is a categorically different guarantee from a permission prompt: a read-only session cannot write, no matter what the model decides, what a file it reads tells it to do, or how tired you were when the dialog appeared.

Codex splits capability from interruption. -s sets what the agent can do at all, with three values: read-only, workspace-write, and danger-full-access. -a sets when it stops to ask, with untrusted, on-request, or never. They are independent, which is why the most useful configuration is one many people never try: a tight sandbox that never interrupts.

# exploration that genuinely cannot write, and never interrupts you
codex exec -s read-only -a never "map how sessions are authenticated"

# may write inside the repository, asks before it wants more
codex -s workspace-write -a on-request

# scriptable review with a machine-readable event stream
codex exec -s read-only -a never --json "review the diff on this branch"

Tab is the other one

Ordinary completion predicts the next tokens where your cursor is. Cursor Tab predicts your next edit, which is usually somewhere else in the file and is usually the mechanical consequence of the change you just made. Codex has no equivalent, and no plausible route to one, because it is not watching your keystrokes.

you edit:     function send(msg: string)
                                        ^ add a second argument, opts

Tab suggests: line 31   send(text)     -> send(text, {})
Tab suggests: line 88   send(body)     -> send(body, {})
Tab suggests: line 154  send(payload)  -> send(payload, { retry: true })

Parallel agents: two real answers now

Two agents editing the same working tree overwrite each other. Both products solve it the same way, with git worktrees, and the difference is how much of it you assemble yourself.

The setup row is the one that decides whether parallel agents work or fail identically. A fresh worktree is a clean checkout: no installed dependencies, no untracked environment file, no build cache. Without a setup step every agent you spawn spends its first three turns rediscovering that, badly, in parallel.

{
  "setup-worktree-unix": [
    "pnpm install --frozen-lockfile",
    "cp ../.env.local .env.local"
  ],
  "setup-worktree-windows": "scripts/setup-worktree.ps1"
}

The cost picture, and what happens at the limit

At the entry tier they cost the same, and the pairing is $40 a month. That is the number most heavy users land on, and it is worth noting that half of it is often already being paid: a great many people asking this question hold ChatGPT Plus and have never run codex.

Which for which hour

Running both, which is what most people do

Because the Codex extension installs inside Cursor, this is one of the few comparisons where the answer can genuinely be "both, in the same window". A setup that takes ten minutes:

Questions people ask

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