RESTful API PUT/PATCH to flip boolean
<p>What is the proper way to flip a boolean over a RESTful API?</p>

<p>Consider, for example, a <code>users/toggle_middle_name</code> endpoint. By default, each user would not have his or her middle name displayed, unless they opted in by hitting an endpoint.</p>

<p>Obviously, this would not be a <code>GET</code> endpoint, as you'd be writing information to the database. But, in a <code>PATCH/PUT</code> request, it's my general understanding that one should send parameters, signifying what data is being set to. So, for example, one would send <code>{show_middle_name: true}</code>. But since this is just a boolean being flipped server-side, ideally, you wouldn't need to know whether to send <code>true</code> or <code>false</code> prior to the call. Just hit the endpoint, and it flips from one to the other, without a value being sent.</p>

<p>The question then becomes, is it okay to just hit a <code>PUT</code>/<code>PATCH</code> endpoint <em>without</em> parameters, and simply return the result in a response? Or are parameter-less <code>PUT</code>/<code>PATCH</code> API calls discouraged? Why or why not?</p>