scmJS docs

Modify Unit Resource Amount

Sets how much ore or gas the mineral fields and geysers of the player in the location hold. There is no unit argument: it applies to every resource the player owns there.

Action 52 · Modify Unit Resource Amount(Player, Amount, Count, Location);

Argument Takes Stored in the action
Player a player or group bytes 16–19
Amount a whole number, 0 to 4,294,967,295 bytes 20–23
Count a number of units, 1 to 255, or All (stored as 0) byte 27
Location a location (Anywhere is location 64) bytes 0–3
Modify Unit Resource Amount("Player 12", 1500, All, "Main");