Stack AI is a no-code tool that allows you to build and deploy AI applications using custom Large Language Models (LLMs) like ChatGPT. With Stack AI, you can design, test, and deploy AI workflows for various use cases including chatbots, document processing, answering questions on databases, and content creation. The platform provides an intuitive graphical interface to connect LLMs, vector databases, tools, and data loaders, making it easy to integrate data from various sources, interact with external APIs, and experiment with different prompts and architectures. Stack AI also offers templates for common workflows, supports fine-tuning for customizing LLMs, and hosts workflows as APIs for fast and reliable access. It is backed by reputable investors and is suitable for teams and developers looking to incorporate AI into their products quickly and efficiently.