Yes, in the library. I think it’s easier to find in the Script Debugger library display. See below for the drop shadow settings.
“mode” would only apply to whether the settings are on or off. For reason they chose “drop” and “none” rather than true or false.
The other properties (in bold) use/return other values.
drop shadow setting
drop shadow setting (noun)Drop shadow settings.
PROPERTIES
angle get/set real The angle at which the shadow is thrown. Can return: fixed (-180 - 180).
blend mode get/set blend mode The blending mode for the drop shadow effect.
class get type class The class descriptor type.
distance get/set number or text The distance between the item and its shadow. Can return: number or string (0 - 1000 points).
effect color get/set swatch The color applied to the drop shadow, specified as a swatch (color, gradient, tint, or mixed ink), or as an array of color values. The color mode dictates the array values: for RGB, specify three values, each in the range 0 to 255, in the format [R,G,B]; for CMYK, specify four values, each as a percentage and each in the range 0 to 100, in the format [C,M,Y,K]; for LAB, specify three values in the format [L,A,B], with L in the range 0 to 100 and A and B in the range -128 to 127.
honor other effects get/set boolean If true, the drop shadow will take into account other non-shadow effects.
knocked out get/set boolean If true, the layer will knock out the drop shadow.
mode get/set mode2 The shadow mode.
noise get/set real The amount (as a percentage) of noise applied to the shadow. (Range: 0 to 100). Can return: fixed (0 - 100).
object reference get drop shadow setting An object reference for the object.
opacity get/set real The opacity of the drop shadow (as a percentage). (Range: 0 to 100). Can return: fixed (0 - 100).
parent get reference The parent of the drop shadow setting (a transparency setting, stroke transparency setting, fill transparency setting or content transparency setting). Can return: transparency setting, stroke transparency setting, fill transparency setting or content transparency setting.
properties get/set record A property that allows setting of several properties at the same time.
size get/set number or text The radius (in pixels) of the blur applied to the drop shadow. (Range depends on the unit type. For points: 0 to 144; for picas: 0p0 to 12p0; for inches: 0 to 2; for mm: 0 to 50.08; for cm: 0 to 5.08; for ciceros: 0c0 to 11c3.128.). Can return: number or string (0 - 144 points).
spread get/set real The amount (as a percentage of the blur width) to spread the footprint of the drop shadow and reduce the radius of the blur. (Range: 0 to 100). Can return: fixed (0 - 100).
use global light get/set boolean If true, uses the global light angle.
x offset get/set number or text The horizontal offset of the drop shadow. Range depends on the unit type. For points: -1000 to 1000; for picas: -83p4 to 83p4; for inches: -13.8889 to 13.8889; for mm: -352.778 to 352.778; for cm: -35.277 to 35.277; for ciceros: -78c2.389 to 78c2.389. Can return: number or string (-1000 - 1000 points).
y offset get/set number or text The vertical offset of the drop shadow. (Range depends on the unit type. For points: -1000 to 1000; for picas: -83p4 to 83p4; for inches: -13.8889 to 13.8889; for mm: -352.778 to 352.778; for cm: -35.277 to 35.277; for ciceros: -78c2.389 to 78c2.389). Can return: number or string (-1000 - 1000 points).