5 August 2026

Claude Code vs Cursor vs ChatGPT Codex: which should you actually use?

The three agents are closer than the marketing suggests. The real differences are the surface you work in, the file your rules live in, and what happens when the agent gets something wrong.

Every few weeks someone asks which AI coding agent they should standardise on. The honest answer is that all three are good, they are converging fast, and the decision is far less permanent than it feels while you are making it.

Here is what actually separates them, based on their own documentation rather than benchmark screenshots.

The short version

Claude Code

Claude Code is terminal-native and built around long-running work. Its memory system is the most developed of the three: CLAUDE.md files at four scopes, an auto-memory directory the agent maintains itself, and path-scoped rules under .claude/rules/ that only load when it touches matching files.

The wrinkle is that Claude Code reads CLAUDE.md and not AGENTS.md. Anthropic's documentation states this directly and suggests a symlink or an @AGENTS.md import as the bridge. Worth knowing before you assume your shared rules file is being read.

Cursor

Cursor is the one that keeps you in an editor rather than a terminal, which for a lot of people is the whole argument. Its rules system moved from a single .cursorrules file to .cursor/rules/ with per-file glob scoping, and it reads AGENTS.md as a simpler alternative.

If your team is already living in VS Code, the switching cost here is close to zero, and that matters more than most feature comparisons admit.

ChatGPT Codex

Codex has the widest surface area: terminal, IDE extension and a cloud environment where tasks run detached. OpenAI also contributed AGENTS.md to the Linux Foundation's Agentic AI Foundation in December 2025, which is why that file is now read by roughly two dozen tools.

Delegated cloud tasks are the differentiator. Whether that is useful depends entirely on whether your work can survive an agent running without you watching it.

The thing the comparison misses

Pick any of the three and you inherit the same underlying property: your rules are context, not configuration.

Anthropic's own docs describe CLAUDE.md as context that Claude "treats as context, not enforced configuration", with "no guarantee of strict compliance". Cursor's docs say rule contents are "included at the start of the model context". Both are accurate, and both mean the same thing — you are adding text to a prompt and hoping it outweighs everything else in the window.

That reframes the decision. Choose on ergonomics — terminal or editor, local or cloud, how the pricing fits your team — because on the dimension people actually worry about, the three are more alike than different.

So which one?

• You live in a terminal and run long tasks: Claude Code.
• You want to stay in your editor: Cursor.
• You want to hand tasks off and come back later: Codex.
• You already pay for two of them: use both, and read on.

You may not have to choose

The assumption buried in "which one should I standardise on" is that you get one. In practice plenty of developers already have two subscriptions, and the interesting question becomes how to use them together rather than which to cancel.

That is what we build. Super Terminal is not an alternative to any of these three — it has no model of its own and writes no code. It sits above them, reads whichever rules files your project already has, and passes them to whichever agent runs. It can also have one vendor's agent write a change and a different vendor's agent review it, which is the one thing none of the three can do alone.

npm install -g super-t

Requires Node.js 20 or later, and works with the subscription you already have.