Yes, this is similar to how that works for URL parameters as well. It is a single item search using the unique id that takes place in the background. It is also how a Do a Search with constraint of unique id = (unique ID value), so there is no real reason to use the toolbox plugin to send the unique ID via javascript and have the javascript to bubble element ‘convert’ it to the actual DB entry unless you are needing to send the value from a reusable element to a page or another reusable element.