This example demonstrates how to extract named entities from user-supplied text and visualize them as an interactive force-directed graph, where each entity is a node sized by its relevance score. It employs the AlchemyAPI via an `httpclient:post()` call to `TextGetRankedNamedEntities` for entity extraction, then uses the `d3.forceSimulation` layout to position nodes by mutual relations. The graph is rendered using D3.js SVG paths, with entity labels and connection lines drawn from the JSON response, and the radial node styling relies on D3’s built-in scales. The code also references an external CSS file for styling but leaves the graph and interaction logic entirely in JavaScript.