Gemini fails with API_KEY_INVALID while OpenAI works (fallback uses dummy_key)

[luisApurata]

Git provider

Github Cloud

System Info

Deployment: GitHub Actions (uses: qodo-ai/pr-agent@v0.33)

Model configured:
gemini/gemini-2.5-flash

Also tested:
o4-mini (OpenAI) → works correctly

API keys:

• GEMINI_API_KEY (from GitHub Secrets)
• OPENAI_KEY (only for testing, works fine)

Notes:

• Gemini API key works correctly outside PR-Agent:
  • GET /v1beta/models works
  • generateContent works
• Issue only happens inside PR-Agent

Bug details

I am using PR-Agent in GitHub Actions with:

config.model: gemini/gemini-2.5-flash
GEMINI_API_KEY from GitHub Secrets

The Gemini API key is valid:

• listing models via API works
• generateContent works via curl

However, inside PR-Agent:

1. It tries gemini/gemini-2.5-flash
2. Fails with:
   API_KEY_INVALID (generativelanguage.googleapis.com)
3. Then falls back to o4-mini
4. That fallback fails with:
   Incorrect API key provided: dummy_key

This happens for:

• PR review
• Code suggestions

Important observation:
Switching to OpenAI (o4-mini with OPENAI_KEY) works correctly.

So:

• same workflow
• same PR-Agent version
• same environment

→ OpenAI works
→ Gemini fails

This suggests an issue in Gemini integration or auth handling inside PR-Agent / LiteLLM.

This behavior looks related to:

• PR_AGENT.MODEL environment variable seems ignored when using Gemini models #2083 (fallback uses dummy_key)
• pr-agent fails to authenticate with Google AI Studio (Gemini) using API Key - DefaultCredentialsError #1965 (Gemini auth issues)

Expected behavior:

• If GEMINI_API_KEY is valid, PR-Agent should use Gemini successfully
• It should not fallback to OpenAI with dummy_key

Failed to generate prediction with gemini/gemini-2.5-flash
Generating prediction with o4-mini
Incorrect API key provided: dummy_key
Failed to generate prediction with any model of ['gemini/gemini-2.5-flash', 'o4-mini']

[luisApurata]

Additional evidence:

• The same GEMINI_API_KEY works outside PR-Agent:

  • GET /v1beta/models succeeds
  • generateContent succeeds

• Inside PR-Agent, Gemini fails with:

  • API_KEY_INVALID (generativelanguage.googleapis.com)

• After that, PR-Agent falls back to o4-mini

• That fallback fails with:

  • Incorrect API key provided: dummy_key

So the key itself appears valid, and the issue seems to happen specifically inside PR-Agent / LiteLLM auth or fallback handling.

[yanukadeneth99]

Hey @luisApurata, could you check if this issue is fixed on the latest v0.34?