3.2 Claude Code

Claude Code uses the Anthropic protocol. The Base URL must not include /v1, otherwise you'll get a 404.

Prepare two things

Setting	Value
Base URL	https://axiomcode.top (note: no /v1)
API Key	sk-axiom-your-key

System requirements

• Node.js 18 or later (LTS recommended)
• OS: Windows 10/11 · macOS · Linux (major distros; WSL also works on Windows)
• Network access to axiomcode.top

Install

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

Environment variables

Set the address and key as environment variables (pick your OS):

macOS / Linux

# Append to ~/.zshrc or ~/.bashrc, then run source to apply
export ANTHROPIC_API_KEY="sk-axiom-your-key"
export ANTHROPIC_BASE_URL="https://axiomcode.top"

Windows PowerShell

# Permanently writes user environment variables; takes effect after reopening the terminal
[Environment]::SetEnvironmentVariable("ANTHROPIC_API_KEY", "sk-axiom-your-key", "User")
[Environment]::SetEnvironmentVariable("ANTHROPIC_BASE_URL", "https://axiomcode.top", "User")

Config file method

settings.json location:

• macOS: ~/Library/Application Support/Claude/settings.json
• Linux: ~/.config/claude/settings.json
• Windows: %APPDATA%\Claude\settings.json

{
  "env": {
    "ANTHROPIC_API_KEY": "sk-axiom-your-key",
    "ANTHROPIC_BASE_URL": "https://axiomcode.top"
  }
}

To set a default model for a single project, create .claude/config.json in the project root:

{
  "model": "claude-sonnet-4-6"
}

Verify

Enter any project directory, run claude, and ask it to analyze the project files:

cd path/to/project
claude

If the model reads and responds to the project content normally, the connection is working. See Supported Models for available models.

The two most common pitfalls

• 404: The Base URL includes /v1 — just remove it.
• 401: The Key has an extra space or is missing its prefix when copied — copy it directly from the console.

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Next: 3.3 OpenCode