But that's the point of something like HTMX, though.

You draw a simple web page with very basic elements, tag them with an HTMX element, and let the client side javascript turn that into something that "does stuff".

I wrote a phone directory with find-as-you-type using Django (because it's what I had lying around) and HTMX (because I read somewhere that it was cool and fun and I should try it, and I bow easily to peer pressure), and then min.css to make it not look shit.

All totally vendored, just download the appropriate .js and .css file and check them into your source control.

When you type it hits an endpoint that returns a bit of HTML that contains a table, and swaps it into a div. The querying part and the drawing part is client-side and there's nothing stopping you passing a query string to the endpoint and getting just a bare table out.

Indeed there's nothing stopping you detecting if it's an HTMX request and only returning the fragment, or if it's "bare" returning a full valid page. You know what? I should do that, I'll log a feature request on my project for it.

I've gotten a little away from the original point.

You use HTMX on the client side, to turn a plain HTML page with no interactivity into something that will pull data from a backend and swap it into the DOM. If you want to return JSON and render that with yet another library you can, but you're probably already filling in the blanks in an HTML template as it is.