DeepSeek V4 for Copilot Chat is a VS Code extension that adds DeepSeek V4 Pro & Flash directly into the GitHub Copilot Chat model picker. You keep Copilot's agent mode, tool calling, skills, and MCP — all powered by DeepSeek. 1. Install the Extension ​ Install VS Code 1.116 or later. Make sure you have a GitHub Copilot subscription (Free / Pro / Enterprise — the free tier works). Install the extension from the Github repo . 2. Get a DeepSeek API Key ​ Go to DeepSeek Platform and create an API key. Copy the key (it starts with sk- ). 3. Configure the API Key in VS Code ​ Open the Command Palette ( Cmd+Shift+P / Ctrl+Shift+P ). Run DeepSeek: Set API Key and paste your key. The key is stored securely in the OS keychain, never on disk.

4. Select the Model and Start Chatting ​ Open Copilot Chat ( Cmd+Shift+I / Ctrl+Shift+I ). Click the model picker at the top-right of the chat panel. Choose DeepSeek V4 Pro or DeepSeek V4 Flash . Start chatting — agent mode, tool calling, and all Copilot features work out of the box. Optional: Configure Thinking Effort ​ In the model picker, click the gear icon next to a DeepSeek model to choose the thinking effort level: None — fastest, no reasoning. High — balanced (default). Max — deep reasoning for complex tasks. Optional: Vision Support ​ DeepSeek V4 is text-only, but the extension handles images automatically. Drop a screenshot into chat and it proxies through another installed Copilot model (Claude, GPT-4o) to describe the image before sending to DeepSeek. Run DeepSeek: Set Vision Proxy Model to pick which model handles image descriptions.