Some of these require no parameters, for example volumeUp or volumeDown, and they work fine.
Some require parameters (or I think in the terminology used internally payloads), for example setVolume. I have found no mechanism to pass that in, at least all the variations on syntax I have tried either are not accepted, or do not work (mostly the former).
Now the actual commands can be made to work. In Node-Red for example, there is this set of nodes (here) which use similar commands, though they are wrapped up inside specific nodes. I have not used them extensively yet, but a relatively complicated thing (open the web browser to a page) worked great.
Now I realize I can, in a kludgy way, hook Node-Red up to Home Assistant, e.g. have a script toggle a button which invokes a flow, which does the thing and re-toggles; hope for no race conditions, etc. Yes, I see how that works, can do.
But what I’d really like is some scripts in HA that just call the services with the right payload. Skip all the fake-event flow invocation.
Is there a syntax I’m just missing, or is HA just not as sophisticated in the use of this as Node-Red?