Swapy is a framework-agnostic tool that allows users to easily convert any layout into a drag-to-swap interface with minimal code. It supports the use of data attributes to specify draggable items and droppable slots, as well as event listeners for tracking changes. The setup process involves installing Swapy, integrating it with your project's layout, and configuring options such as animation settings. Examples for using Swapy with popular frameworks like React, Vue, and Svelte are also provided.