Some of a sprite's internal states (like x, y, direction) are built-in "variable" UI objects that are immediately available to the sprite's script. But many aren't. Hopefully it would be easy to make these available as built-in UI objects:
Looks: (costume)
Looks: (effect type)
Looks: (effect value)
Looks: (size)
Looks: <hidden?>
Pen: <down?>
Pen: (color)
Pen: (shade)
Pen: (size)
Sound: <sound playing?>
Sound: (sound)
Sound: <drum playing?>
Sound: (drum)
Sound: (instrument)
Sound: <note playing?>
Sound: (note)
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