const util = require('util'); // Class with custom inspection class Person { constructor(name, age) { this.name = name; this.age = age; this._private = 'hidden information'; } // Custom inspect method [util.inspect.custom](depth, options) { return `Person(${this.name}, ${this.age})`; } } const kai = new Person('Kai', 30); // Custom inspection is used console.log(util.inspect(kai)); // Person(Kai, 30) // Directly using console.log also uses custom inspection console.log(kai); // Person(Kai, 30)