LoopGPT is an innovative open-source reimplementation of the Auto-GPT project, packaged neatly for Python developers seeking flexibility and control over AI agent creation. By emphasizing modularity and extensibility, LoopGPT empowers developers to easily customize and extend AI functionalities to suit specific needs. It is designed with a plug-and-play API that simplifies integration and boasts compatibility with GPT-3.5, ensuring state-of-the-art language model support. With minimal prompt overhead, LoopGPT optimizes efficiency without compromising on performance. It also includes human-in-the-loop functionality, facilitating seamless collaboration between AI systems and human operators. Additionally, its full state serialization feature ensures that developers can save and restore AI states effortlessly, enhancing reliability and continuity in AI processes. Whether for commercial or personal projects, LoopGPT offers a robust platform for advancing AI development and deployment.