The Gemini provider uses Google's OpenAI-compatible endpoint
(generativelanguage.googleapis.com/v1beta/openai) but the client
routing condition in client.ts only checked CLAUDE_CODE_USE_OPENAI
and CLAUDE_CODE_USE_GITHUB — CLAUDE_CODE_USE_GEMINI was missing.
This caused every Gemini request to fall through to the Anthropic
client path. Since ANTHROPIC_API_KEY is not set when using Gemini,
the Anthropic SDK threw:
"Could not resolve authentication method. Expected either apiKey
or authToken to be set."
Fix: add CLAUDE_CODE_USE_GEMINI to the OpenAI shim routing condition
so Gemini requests correctly reach createOpenAIShimClient(), which
maps GEMINI_API_KEY → OPENAI_API_KEY and sets OPENAI_BASE_URL to
the Google endpoint.
Closes#176
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
