Codex with ChatGPT

1. What is Codex with ChatGPT?

Codex with ChatGPT is an add-on (a "Skill") for Codex, OpenAI's coding assistant. It splits the work in two: the ChatGPT web app does the thinking (planning and reviewing), and Codex does the doing (editing files, running commands, running tests). The author's reasoning is simple: the paid ChatGPT plan you already have usually has unused capacity on the web, while Codex spends its own limited quota on planning. This tool moves the "thinking" to the web subscription you are already paying for.

To be direct: this is a tool for people who already use Codex to write code. It is not a new chat app and there is no .exe installer. That said, the author designed it so that a non-technical person can still install it: you paste one request into Codex and Codex does nearly everything.

The project is free and open source (MIT license) and needs no API key. It is a community project, not an OpenAI product, and is not endorsed by OpenAI.

A good fit if:

• You already use Codex on a code project and have a paid ChatGPT plan (the project mentions Plus/Pro).
• You want ChatGPT to plan and review while Codex only executes.
• You do not want your whole project folder uploaded: ChatGPT reads just the lines it needs over a read-only connection.

Not a good fit if:

• You do not use Codex, or you only want an AI chat for everyday questions.
• You only have a phone. This runs on a computer.
• You do not have a paid ChatGPT plan.

2. What do you need?

Item	Details
Computer	The docs give clear steps for macOS and Windows. For Linux, the cloudflared step only says to follow Cloudflare's own instructions.
Codex	OpenAI's coding assistant, installed and signed in. The Skill uses the browser built into Codex to open ChatGPT. Official page: https://openai.com/codex/
Paid ChatGPT account	The project mentions Plus/Pro. Check OpenAI's site for plan prices; this project charges nothing on top.
Node.js 20 or newer	The runtime for programs written in JavaScript. Download: https://nodejs.org/
Git	The tool that downloads source code from GitHub. Download: https://git-scm.com/downloads
cloudflared	A small Cloudflare program that creates the secure link ChatGPT uses to read files on your machine. The Skill installs it during setup.
Cloudflare account and domain	Optional. Only needed if you want a permanent connection address.
Internet	Required, because ChatGPT runs on the web.

Note: If Node.js, Git or cloudflared is missing, you do not have to install it yourself. The request in Step 1 tells Codex to check and install whatever is missing (Homebrew on macOS, winget on Windows).

3. Step-by-step installation

There are two routes. Route A is for beginners: Codex does it all. Route B is for people comfortable with a command line.

Step 1 (Route A): Paste the install request into Codex

Open Codex, start a new conversation and paste this:

Please install and configure "Codex with ChatGPT" for me and do everything yourself:
1. Check that git and Node.js 20 or newer are present; install what is missing
   (Homebrew on macOS, winget on Windows). Install cloudflared too.
2. Clone https://github.com/XiaoDuoYa/codex-with-chatgpt into ~/codex-with-chatgpt
   (if it already exists, run git pull).
3. In that folder run: corepack pnpm install, then corepack pnpm build.
4. Copy skill/SKILL.md to ~/.codex/skills/codex-with-chatgpt/SKILL.md and change the
   line "The codex-with-chatgpt checkout lives at:" to the real path.
5. Follow the first-time setup section of SKILL.md (run c2c setup, open ChatGPT in
   the built-in browser to create the connector and enter the pairing code).
6. Only stop for me when a login or a verification code is needed, one action at a time.
7. When finished, show me the checklist and confirm the file-read test passed.

This is a condensed version of the steps the project publishes. The original wording (English and Chinese) is in the project README: https://github.com/XiaoDuoYa/codex-with-chatgpt

What success looks like: Codex starts running commands one by one and reports progress. You just wait.

Step 2: Sign in when asked

During setup Codex may pause and ask you to:

• Sign in to ChatGPT in the browser window Codex opens.
• Turn on "Developer mode" in ChatGPT if it is off. The settings page is https://chatgpt.com/#settings/Security
• Sign in to Cloudflare, only if you chose a permanent address.

The pairing code is single-use and expires after about 5 minutes. Codex creates and enters it; you do not copy it by hand.

What success looks like: after you sign in, Codex carries on without further questions.

Step 3: Check the result

When it is done, Codex shows a five-line checklist:

✓ Project detected
✓ Workspace Bridge started
✓ Secure connection established
✓ ChatGPT connected
✓ File read test passed

The last line reads "Ready." Five ticks mean the install worked.

Route B: Manual install for command-line users

Download the source and build it:

git clone https://github.com/XiaoDuoYa/codex-with-chatgpt
cd codex-with-chatgpt
corepack pnpm install
corepack pnpm build

Then copy the repo's skill/ folder to ~/.codex/skills/codex-with-chatgpt/, open the copied SKILL.md and change the line "The codex-with-chatgpt checkout lives at:" to the folder you just cloned. Finally tell Codex: "Set up Codex with ChatGPT."

4. First use

Open Codex in your project folder and give it a task as usual, naming the tool in your request. For example:

Use Codex with ChatGPT to implement: a light/dark theme toggle on the home page.

For a project folder it has not seen before, you are asked to do one thing, once: create a "Project" in ChatGPT, name it after the project folder and choose project-only memory. If the ChatGPT sidebar has no Projects row, hover over Chats, click the three-dot menu and choose Organize by project.

After that the loop runs on its own:

1. Codex sends ChatGPT a short message describing the task.
2. ChatGPT reads the relevant files itself over the read-only connection and returns a plan.
3. Codex edits the code and runs tests on your machine.
4. ChatGPT inspects the real changes and the test results, then comments.
5. This repeats until the task is done.

What the first result looks like: in Codex, the code has been changed. In ChatGPT, inside the Project you created, there is a conversation holding the plan and the review.

5. Common problems and fixes

The author's first advice for any problem: tell Codex "Update Codex with ChatGPT" and try again. The latest version fixes most known issues. If it still fails, ask Codex to run the health check:

c2c doctor

It checks Node, the project folder, the bridge and the connection, and repairs what it can.

Symptom	Cause	Fix
After quitting and reopening Codex, ChatGPT cannot connect	The default connection address is a temporary Cloudflare address. It stops working when Codex is closed.	Ask Codex to run c2c doctor. In ChatGPT (https://chatgpt.com/plugins), delete the connector for this one project and let Codex create it again with the new address. Do not click "Reconnect": the old address is dead.
Pairing code reported as invalid or expired	Codes are single-use and expire after about 5 minutes.	Wait until ChatGPT's "Authorize" page is on screen, then create a fresh code with c2c pair.
Connection keeps dropping on an office or school network	cloudflared uses the QUIC protocol by default, which many networks block.	Set the environment variable C2C_TUNNEL_PROTOCOL=http2 and restart the bridge. You can ask Codex to do this.
Message that cloudflared is not installed	The cloudflared program is missing.	macOS: brew install cloudflared. Windows: winget install Cloudflare.cloudflared.
Every new Codex conversation "repairs the connection" from scratch	Codex runs in a sandbox and cannot write to the tool's state folder.	Ask Codex to run c2c sandbox-allow. It adds that folder to the writable list in the Codex configuration.
ChatGPT reports ACCESS_DENIED_SENSITIVE_FILE when reading a file	Not a bug. .env files, keys and credentials are blocked on purpose.	Nothing to fix. To block more files, add rules to a .c2cignore file.
No Projects row in ChatGPT	The sidebar is in a different view.	Hover over Chats, click the three-dot menu, choose Organize by project.

If you are completely stuck, ask Codex to rebuild everything:

c2c stop
c2c setup

6. Uninstalling and updating

Updating. The Skill checks GitHub once a day and updates itself when a new version is out. You can also tell Codex at any time: "Update Codex with ChatGPT". The latest version when this guide was written is v0.1.3 (released 11 September 2026).

Uninstalling. The project has no dedicated uninstall document yet. Based on the places the docs say the tool stores things, remove it in this order:

1. Ask Codex to run c2c stop to shut down the bridge, and c2c unpair to revoke the access you granted.
2. Open https://chatgpt.com/plugins and delete the connector for each project.
3. Delete the Skill folder: ~/.codex/skills/codex-with-chatgpt.
4. Delete the downloaded source folder: ~/codex-with-chatgpt (or wherever you cloned it).
5. Delete the state folder. On macOS: ~/Library/Application Support/codex-with-chatgpt. On Windows: %LOCALAPPDATA%\codex-with-chatgpt.

If unsure, just ask Codex: "Completely remove Codex with ChatGPT from my machine, and list what you will delete first."

7. Frequently asked questions

Does it cost money? The tool itself is free and needs no API key. You still need a paid ChatGPT plan and access to Codex. See OpenAI's site for those prices.

Is my code uploaded? According to the project docs, the project folder is never uploaded as a whole. ChatGPT reads exactly the lines it needs over an authenticated read-only connection. The bridge server has no write, delete or command tools at all. .env files, keys and credentials are denied by default. Still, the lines ChatGPT does read travel through a Cloudflare tunnel to ChatGPT, so think twice for highly confidential projects.

Does it need internet? Yes. ChatGPT runs on the web and the connection goes through Cloudflare.

Is this an OpenAI product? No. The author states it is an unofficial community project, not affiliated with or endorsed by OpenAI. It is at its first version (V1).

Do I need to understand MCP, OAuth or tunnels? No. The author designed it so Codex configures everything. You only sign in when asked.