> ## Documentation Index
> Fetch the complete documentation index at: https://docs.asklethe.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Claude Code

> Point Claude Code at LETHE by swapping the Anthropic base URL.

Claude Code talks to the Anthropic Messages API, so it works against LETHE's [Messages API](/api-reference/messages) with just environment variables, no code changes.

```env .env theme={null}
export ANTHROPIC_BASE_URL="https://asklethe.ai"
export ANTHROPIC_AUTH_TOKEN="$LETHE_API_KEY"
export ANTHROPIC_DEFAULT_OPUS_MODEL="lethe"
export ANTHROPIC_DEFAULT_SONNET_MODEL="lethe"
export ANTHROPIC_DEFAULT_HAIKU_MODEL="lethe"
```

Get `$LETHE_API_KEY` from [Authentication](/api-reference/authentication). Claude Code's default model picker ids (`opus`, `sonnet`, `haiku`) are automatically aliased to `lethe` server-side, so setting all three env vars to `lethe` is intentional, not a placeholder.