Gemini ↔︎ OpenAI Proxy
Serve Google Gemini 2.5 Pro (or Flash) through an OpenAI-compatible API.
Plug-and-play with clients that already speak OpenAI—SillyTavern, llama.cpp, LangChain, the VS Code Cline extension, etc.
✨ Features
✔ | Feature | Notes |
---|---|---|
/v1/chat/completions |
Non-stream & stream (SSE) | Works with curl, ST, LangChain… |
Vision support | image_url → Gemini inlineData |
|
Function / Tool calling | OpenAI “functions” → Gemini Tool Registry | |
Reasoning / chain-of-thought | Sends enable_thoughts:true , streams <think> chunks |
ST shows grey bubbles |
1 M-token context | Proxy auto-lifts Gemini CLI’s default 200 k cap | |
CORS | Enabled (* ) by default |
Ready for browser apps |
Zero external deps | Node 22 + TypeScript only | No Express |
🚀 Quick start (local)
git clone https://huggingface.co/engineofperplexity/gemini-openai-proxy
cd gemini-openai-proxy
npm ci # install deps & ts-node
# launch on port 11434
npx ts-node src/server.ts
Optional env vars
PORT=3000 change listen port
GEMINI_API_KEY=<key> use your own key
Minimal curl test
bash
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curl -X POST http://localhost:11434/v1/chat/completions \
-H "Content-Type: application/json" \
-d '{
"model": "gemini-2.5-pro-latest",
"messages":[{"role":"user","content":"Hello Gemini!"}]
}'
SillyTavern settings
Field Value
API Base URL http://127.0.0.1:11434/v1
Model gemini-2.5-pro-latest
Streaming On
Reasoning On → grey <think> lines appear
🐳 Docker
bash
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# build once
docker build -t gemini-openai-proxy .
# run
docker run -p 11434:11434 \
-e GEMINI_API_KEY=$GEMINI_API_KEY \
gemini-openai-proxy
🗂 Project layout
pgsql
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src/
server.ts – minimalist HTTP server
mapper.ts – OpenAI ⇄ Gemini transforms
chatwrapper.ts – thin wrapper around @google/genai
remoteimage.ts – fetch + base64 for vision
package.json – deps & scripts
Dockerfile
README.md
📜 License
MIT – free for personal & commercial use.