Hi, wanted to bring back the topic after these months since it would be really useful to have a standard stepLevel command, especially in groups!
Currently there are at least three custom drivers that implement steps for lights (for Zigbee, for Matter and a virtual dimmer). Each one uses its own custom capability of course, but they all have in common a first numeric argument for the step value percent.
Even if there’s no user interface for that and initially it’s only available through Rules API and not even groups, at least create the capability so we all use the same and stock drivers can include it too and send the native Step command.
For the capability they can copy mine,panelorange55982.stepLevel which is the most generic and matches the native options in Zigbee and Matter including also the transition time and the withOnOff behaviour.
When it’s created, ideally SmartThings groups could implement it since currently the workarounds either produce popcorn effect having to address individual lights without “native hub handlers” or don’t know the actual brightness of the group so the target brightness is not always the correct one.