Claude Code speaks the native Anthropic protocol. Point its base URL, auth token and model at this gateway; the environment variables below are the same as the Claude Code preset on the tool integration page.
Client versions and configuration screens change; if an option name differs in your version, the equivalent setting is the one that overrides the API base URL. The API key in the examples is a placeholder.
Upstream protocol references: OpenAI API reference · Anthropic (Claude) API overview · Google Gemini API docs
Write these into your shell profile, or into env in ~/.claude/settings.json.
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