Environment Setup

Claude Code, Codex, and Gemini CLI can all be installed through npm. Prepare your environment according to your operating system.

MacOS

brew install node

Linux (Ubuntu/Debian)

sudo apt install nodejs npm

Windows

Step 1: Install Chocolatey

1) Open PowerShell as Administrator.

2) Run the following command and confirm with Y:

Set-ExecutionPolicy -ExecutionPolicy RemoteSigned -Scope CurrentUser

3) Then run:

[System.Net.ServicePointManager]::SecurityProtocol = [System.Net.ServicePointManager]::SecurityProtocol -bor 3072; iex ((New-Object System.Net.WebClient).DownloadString('https://community.chocolatey.org/install.ps1'))

4) After installation completes, close PowerShell, reopen it as Administrator, and verify:

choco --version

Step 2: Install Node.js and Git

choco install nodejs git -y

Refresh environment variables:

$env:Path = [System.Environment]::GetEnvironmentVariable("Path","Machine") + ";" + [System.Environment]::GetEnvironmentVariable("Path","User")

Verify installation:

node --version
npm --version
git --version

Optional: Install Common CLI Tools Together

If you plan to use Claude Code, Codex, and Gemini CLI together, install them after Node.js and npm are available:

npm i -g @anthropic-ai/claude-code
npm i -g @openai/codex@latest
npm i -g @google/gemini-cli

Windows users should open a new PowerShell window after installation, then verify:

claude --version
codex --version
gemini --version