Tooltips are powered by Tippy.js. We've wrapped them in a Stimulus controller so you can easily add them anywhere in your application.
Add a data-controller="tooltip" data-tippy-content="My tooltip" to the element you want to add the tooltip to. You can set options using data attributes without writing any JS.
See also Clipboard which uses Tippy.js.
<button class="btn btn-secondary" data-controller="tooltip" data-tippy-content="I'm a Tippy tooltip!" data-tippy-delay="0" data-tippy-arrow="true" data-tippy-size="regular" data-tippy-animation="fade">Hover over me</button>