copilot-lm-proxy 0.2.0

Python client for accessing GitHub Copilot LLMs via local proxy

Copilot Proxy

Access GitHub Copilot's LLM models (GPT-4.1, GPT-5.x, Claude, Gemini, and more) from any Python script via a local HTTP server. Works with the standard OpenAI Python client. Zero dependencies.

Prerequisites

• VS Code with the GitHub Copilot extension (requires a Copilot subscription)
• Node.js (v18+) — for building the VS Code extension
• Python 3.10+

Quick Start

One-command install

git clone https://github.com/hsaghir/copilot-proxy.git
cd copilot-proxy
make install

This builds the VS Code extension, installs it, and installs the Python client. Then reload VS Code (Ctrl+Shift+P → "Reload Window").

Manual install (without Make)

1. Install the VS Code extension:

cd vscode-extension
npm install
npm run compile
npx @vscode/vsce package --allow-missing-repository
code --install-extension copilot-proxy.vsix

Reload VS Code. The proxy starts automatically on http://127.0.0.1:19823.

2. Install the Python client:

pip install -e .
# or with uv:
uv pip install -e .

Verify it works

from copilot_proxy import ask
print(ask("Hello!"))

Usage

Python Client (zero dependencies)

from copilot_proxy import ask, chat, list_models

# Simple question (uses default model)
response = ask("Explain neural networks")

# Use a specific model
response = ask("Explain quantum computing", model="gpt-4.1")

# Multi-turn conversation
response = chat([
    {"role": "system", "content": "You are a helpful assistant."},
    {"role": "user", "content": "What is 2+2?"}
], model="claude-sonnet-4")

# List all available models
for m in list_models():
    print(f"  {m['id']} ({m['vendor']})")

OpenAI Python Client (drop-in compatible)

from openai import OpenAI

client = OpenAI(base_url="http://127.0.0.1:19823/v1", api_key="dummy")

response = client.chat.completions.create(
    model="gpt-4.1",
    messages=[{"role": "user", "content": "Hello!"}]
)
print(response.choices[0].message.content)

# Streaming
for chunk in client.chat.completions.create(
    model="gpt-4.1",
    messages=[{"role": "user", "content": "Tell me a joke"}],
    stream=True
):
    print(chunk.choices[0].delta.content or "", end="")

HTTP API (curl)

# List models
curl http://127.0.0.1:19823/v1/models

# Chat completion
curl http://127.0.0.1:19823/v1/chat/completions \
  -H "Content-Type: application/json" \
  -d '{"model": "gpt-4.1", "messages": [{"role": "user", "content": "Hello!"}]}'

Available Models

With a GitHub Copilot subscription you get access to many models. Run list_models() or curl http://127.0.0.1:19823/v1/models to see all. Common ones:

Model	ID
GPT-4.1	gpt-4.1
GPT-5.1	gpt-5.1
GPT-5.4	gpt-5.4
GPT-4o	gpt-4o
Claude Sonnet 4.6	claude-sonnet-4.6
Claude Opus 4.6	claude-opus-4.6
Claude Haiku 4.5	claude-haiku-4.5
Gemini 2.5 Pro	gemini-2.5-pro
Gemini 3 Pro	gemini-3-pro-preview

Structured Output with Pydantic

pip install copilot-lm-proxy[pydantic]

from pydantic import BaseModel
from copilot_proxy import ask
import json

class MovieReview(BaseModel):
    title: str
    rating: float
    summary: str

schema = MovieReview.model_json_schema()
prompt = f"Review Inception. Return JSON matching this schema: {json.dumps(schema)}"

response = ask(prompt, model="gpt-4.1")
review = MovieReview.model_validate_json(response)

Configuration

The proxy uses sensible defaults but everything is configurable:

Setting	Default	How to change
Proxy port	19823	VS Code: Settings → Copilot Proxy → Port
Python base URL	http://127.0.0.1:19823	Env var COPILOT_PROXY_URL or CopilotClient(base_url=...)

Error Handling

from copilot_proxy import ask, ProxyConnectionError, ModelNotFoundError

try:
    result = ask("Hello", model="gpt-4.1")
except ProxyConnectionError:
    print("Proxy not running — reload VS Code")
except ModelNotFoundError:
    print("Model not available")

Troubleshooting

Problem	Fix
Connection refused on port 19823	Reload VS Code. Check Output → "Copilot Proxy" panel.
EADDRINUSE: address already in use	lsof -ti:19823 | xargs kill -9 then reload VS Code.
Empty responses	Make sure you're signed into GitHub Copilot in VS Code.
No models available	Open Copilot Chat in VS Code first to initialize the session.
Model returns empty but gpt-4o works	Try specifying a different model — not all models are available in all regions.

Development

pip install -e ".[dev]"      # install with test deps
pytest tests/test_client.py -v  # unit tests (no proxy needed)
pytest -v                       # all tests (proxy must be running)

See CONTRIBUTING.md for details.

License

MIT