HASS.Agent has slowly, but steadily, been gaining feature parity with other applications aiming to integrate Home Assistant with your Windows PC, notebook, or tablet. The most recent release turns Windows into a Home Assistant controllable media player. This functionality does have a few caveats though, of which you can learn in this short overview.
HASS.Agent is not a universal fit
The first thing to note is that this integration will not support every Windows application you throw at it. Specifically mentioned in the release notes is the VLC media player. Put simply, the application you want to control has to use the Windows.Media APIs. Luckily, other popular apps, such as Spotify for Windows and even YouTube running in a Chrome browser, are supported.
As you might have been able to tell by the screenshots, this integration unfortunately does not support any cover art. So while you do get to see the currently playing track, along with the artist, you have to look at a drab looking media player in your Dashboard. Incidentally, when playing a YouTube video in Chrome, it will display the channel's name and the title of the video.
WebView lets you instantly open websites remotely
The second big addition to HASS.Agent 2022.12 is the WebView command. This allows you to remotely open any site on your Windows PC using Home Assistant. The WebView command uses Microsoft Edge's core to display the sites, without having to launch a full-fledged browser.
I have not found much use for this command yet, and in my case, I have found it to not work very well with multiple monitors.