Claude Code

Claude Code is Anthropic's official CLI for Claude. FastMetal provides native Anthropic API support, enabling seamless integration with Claude Code using any supported model.

Installation

Install Claude Code globally using npm:

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

Configuration

Configure Claude Code to use the FastMetal API by setting these environment variables:

export ANTHROPIC_AUTH_TOKEN="your-api-key"
export ANTHROPIC_BASE_URL="https://api.fastmetal.ai"
export ANTHROPIC_DEFAULT_HAIKU_MODEL="anthropic-claude-haiku-4-5"
export ANTHROPIC_MODEL="your-model-name"  # optional

ANTHROPIC_AUTH_TOKENYour FastMetal API key

ANTHROPIC_BASE_URLThe Anthropic-compatible API endpoint

ANTHROPIC_DEFAULT_HAIKU_MODELThe model Claude Code uses for light background work such as titles. Claude Code's built-in Haiku model IDs are not FastMetal model names and are rejected, so set this to a FastMetal model (for example anthropic-claude-haiku-4-5)

ANTHROPIC_MODELThe model to use (optional)

Two settings matter: use ANTHROPIC_AUTH_TOKEN (not ANTHROPIC_API_KEY — Claude Code sends that as an x-api-key header, which FastMetal rejects), and set ANTHROPIC_BASE_URL to the host root with no /v1 suffix (Claude Code appends /v1/messages itself). A /v1 suffix produces /v1/v1/messages and a 404 that Claude Code misreports as a model-access problem.

Usage

Once configured, use Claude Code as normal. All requests will be routed through FastMetal:

Tips

Monitor your usage on the dashboard to track spending

Use environment variables to switch between models

Check the API documentation for supported features