CLI Setup Guide

This guide covers the basic installation and setup of Claude Code, Codex, and Gemini CLI.

Before You Start

Before configuring command-line tools, make sure you understand the following basics:

• API Keys
• API URL
• Available Models

Environment Requirements

This section covers the installation of Node.js, npm, and related dependencies.

Install with Winget (Windows)

Open a terminal and run:

winget install OpenJS.NodeJS.LTS

After installation, run node -v and npm -v in a new terminal to verify.

Install with Brew (macOS)

Open a terminal and run:

brew install node

If Homebrew is not installed, refer to the official Homebrew documentation.

Verify Environment

Run the following commands and confirm that version numbers are returned.

node -v

Tip

Using a faster npm mirror may improve download speed in some regions: npm config set registry https://registry.npmmirror.com

npm -v

Claude Code Setup

Install

Windows:

npm install -g @anthropic-ai/claude-code

On macOS or Linux, use sudo if required:

sudo npm install -g @anthropic-ai/claude-code

Environment Variables

Windows:

setx ANTHROPIC_API_KEY "sk-xxxxxxxxxxxxxx" # Replace with your API key

macOS/Linux:

export ANTHROPIC_API_KEY="sk-xxxxxxxxxxxxxx"
export ANTHROPIC_BASE_URL="https://api.vlxflux.io"

Config File

Create or edit .claude.json in your home directory:

{
  "theme": "dark",
  "apiBaseUrl": "https://api.vlxflux.io"
}

Launch

claude

Codex Setup

Install

Windows:

npm install -g codex-cli

If elevated permission is required:

sudo npm install -g codex-cli

Environment Variables

Windows:

setx OPENAI_API_KEY "sk-xxxxxxxxxxxxxx" # Replace with your API key

macOS/Linux:

export OPENAI_API_KEY="sk-xxxxxxxxxxxxxx"
export OPENAI_BASE_URL="https://api.vlxflux.io/v1"

Config File

Edit ~/.codex/config.json:

{
  "api_key": "sk-xxxxxxxxxxxxxx",
  "base_url": "https://api.vlxflux.io/v1",
  "model": "gpt-4o"
}

Launch

codex

Gemini CLI Setup

Install

Windows:

npm install -g @google/generative-ai-cli

If elevated permission is required:

sudo npm install -g @google/generative-ai-cli

Environment Variables

Run the following in macOS/Linux:

export GEMINI_API_KEY="sk-xxxxxxxxxxxxxx"
export GOOGLE_GEMINI_BASE_URL="https://api.vlxflux.io"

Config File

Edit ~/.gemini/config.json:

{
  "api_key": "sk-xxxxxxxxxxxxxx",
  "base_url": "https://api.vlxflux.io"
}

Launch

gemini

FAQ

API key does not take effect?

Restart the terminal, or use echo to confirm the environment variable is loaded.

Model not found?

Make sure the model name is correct and the current key has permission to use it.

Cannot connect to the server?

Check whether the BASE_URL is correct, whether proxy settings interfere, and whether DNS resolution works properly.

Claude Code unauthorized?

Try exporting ANTHROPIC_BASE_URL again before launching.

export ANTHROPIC_BASE_URL="https://api.vlxflux.io"
claude

Extra Configuration

Switch Models Dynamically

Add an alias in ~/.bashrc or ~/.zshrc:

alias claude_opus='export ANTHROPIC_MODEL="claude-3-opus-20240229" && claude'

Then run:

source ~/.zshrc
claude_opus

Quiet Output

codex "写一段快速排序" --quiet