Which styles the knob works on; see stylingKnobAppliesTo.
Whether the knob has anything to work on in the loaded style. false means setting it would
do nothing, and the SDK also warns once in the console when that happens. Check this before
offering the knob in a UI or to an agent. Map-level knobs are always available bar
view.terrain, which needs the style to carry an elevation source.
The value in effect right now: the override if there is one, otherwise the default.
The value the loaded style ships with. undefined when the style defines it as a data-driven
expression that no single value stands for; reset still restores it exactly.
The knob's id, as accepted by StylingModule.set.
Optionaloptions?: readonly string[]The valid values, for enum knobs.
Optionalrange?: StylingKnobRangeThe range of valid values, for factor and number knobs.
Narrows the shared KnobDescriptor: styling ids and value types are known, range.step is
always given, and available / appliesTo are required — every styling knob answers both.
One entry of the styling catalogue returned by StylingModule.describe: everything a UI or an agent needs to offer the knob, validate a value for it and show its state.