It would be useful to be able to define parameter visibility in scripts, e.g. in Python:

# @String(label="Label", visibility="message", value="My message") text

In a Java command, this can currently be done using the enum org.scijava.ItemVisibility:

@Parameter(persist = false,
           visibility = org.scijava.ItemVisibility.MESSAGE,
           required = false)
private String message= null;

The enum doesn't seem to be accessible during parameter harvesting in scripts, so this might require a fall-back to Strings, similar to the style parameter.