Support · Codex

Connect OpenAI Codex CLI

This guide shows you how to use OpenAI Codex CLI for AI chat inside Cyer. Codex uses your existing ChatGPT subscription. Cyer does not add a separate AI bill.

You will NEED a ChatGPT account

Sign up at chatgpt.com and make sure you have a paid ChatGPT plan that works with Codex CLI. You also need Node.js installed on your PC to install the Codex command-line tool.

  1. 1

    Install Node.js (if needed)

    Codex CLI installs through npm (a Node.js tool). If you do not have Node yet, download the LTS version from nodejs.org and install it.

    Open PowerShell and run node --version. If you see a version number, you are ready.

  2. 2

    Open Cyer Settings

    Launch Cyer from the system tray. Open SettingsIntegrations. Find OpenAI Codex CLI and click Connect.

    The Connect Codex window opens with four numbered steps.

    Cyer Settings Integrations section — same area as Claude, look for OpenAI Codex CLI row
    Open Integrations in Settings and click Connect on the Codex row.
  3. 3

    Install Codex CLI

    On Step 1: Install Codex CLI:

    1. Click Get Codex CLI to open the npm package page, or run this in PowerShell:

    npm install -g @openai/codex

    1. Wait for the install to finish.
    2. Back in Cyer, click Re-check.

    Step 1 should show “Detected” with a version number.

    Connect Codex dialog step 1 with npm install command and Get Codex CLI button
    Install Codex globally, then Re-check in Cyer.
  4. 4

    Sign in with ChatGPT

    On Step 2: Sign in, click Sign in with ChatGPT.

    1. A Codex sign-in terminal window opens — keep it open.
    2. Your browser opens the ChatGPT login page. Sign in with your account.
    3. Cyer polls until it detects sign-in. This can take up to a minute.

    If Cyer is still waiting, click I've signed in after you finish in the browser.

    Connect Codex wizard step 2 with Sign in with ChatGPT button and sign-in instructions
    In Connect Codex, click Sign in with ChatGPT — same terminal + browser pattern as Claude.
  5. 5

    Verify and MCP

    On Step 3, click Verify connection if needed. You should see “Ready to chat.”

    On Step 4: Cyer MCP, Cyer may auto-install MCP config. If not, click Install MCP config once. Look for MCP CONFIGURED.

    Connect Codex wizard with all four steps complete
    All steps green — Codex is connected.
  6. 6

    Choose Codex as your cloud AI

    If you also use Claude, tell Cyer which cloud AI to prefer. In Settings → Advanced, open AI brain (hybrid).

    • Set Preferred cloud provider to Codex.
    • Leave Prefer cloud AI over Ollama checked if you want Codex first.

    Open Chat and send a test message.

  7. ?

    Troubleshooting

    npm install fails

    • Run PowerShell as Administrator and try again.
    • Make sure Node.js LTS is installed from nodejs.org.

    Cyer says Codex is not installed

    • Run codex --version in PowerShell. If it fails, close and reopen Cyer after install.

    Sign-in not detected

    • Click Refresh status or I've signed in.
    • Keep the Codex terminal window open until Cyer confirms.

Still stuck?

Email us at hello@cyer.app. Include any error text from Cyer or the terminal.

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