This example shows a collapsible tree diagram where each node is a box displaying metadata such as type, code, and version. The visualization uses a hierarchical JSON dataset, with nodes color-coded by type and links labeled with their direction (SYNC or ASYN). The implementation uses d3.v3’s `d3.layout.tree` to compute the layout and SVG for rendering, with CSS transitions providing smooth expand and collapse animations. Custom tooltips appear on hover, and zooming is handled via `d3.behavior.zoom`.