CLIProxyAPI is an open-source proxy server designed to provide OpenAI, Gemini, Claude, Codex, and Grok compatible API interfaces for command-line interfaces (CLI). It enables users to access various large language models—including Moonshot AI's Kimi K3 (a 2.8 trillion parameter model with a 1-million-token context window), OpenAI's GPT series, Anthropic's Claude series, Google's Gemini series, and xAI's Grok series—through local endpoints. Technically, the tool supports multiple CLI accounts via OAuth or compatible API interfaces and implements round-robin load balancing for Gemini, OpenAI, Claude, and Grok providers. Key functional features include support for streaming, non-streaming, and WebSocket responses, function calling, tools, and multimodal inputs (text and images). Developers can integrate the service using a reusable Go SDK. The project also supports OpenAI-compatible upstream providers like OpenRouter via configuration. For advanced management, the ecosystem includes various community-driven tools for real-time quota tracking, such as monitoring 5-hour and weekly usage windows, and management centers like CPA-Manager for request-level monitoring and cost estimation using SQLite storage.