Zero-Cost Claude Code: A Reverse Engineering Guide to GitHub Copilot Implementation

This article details an innovative solution that reverse engineers GitHub Copilot Pro into a Claude API through the open-source copilot-API project, enabling developers to use Claude Code at zero cost. The article provides a complete operational guide from environment preparation to service configuration, including Node.js environment installation, copilot-API and Claude Code installation steps, as well as detailed proxy service startup and Claude Code configuration methods. This technical solution not only implements the basic functions of Claude Code but also supports advanced features such as tool calling and file reading/writing, providing developers with an economical and efficient AI-assisted programming option. This reverse engineering approach demonstrates the interoperability possibilities between different AI tools, offering valuable technical reference for the open-source community and developer groups.