[Skillet`]

You can't because Zeex made the structure using a define,you'll need to add such an option by yourself if you want to use the command proccecor like that.
zcmd.inc

pawn Код:

#define COMMAND:%1(%2)          \
            forward cmd_%1(%2); \
            public cmd_%1(%2)       
            
#define CMD:%1(%2) \
            COMMAND:%1(%2)

#define command(%1,%2,%3) \
            COMMAND:%1(%2, %3)      
      
#define cmd(%1,%2,%3) \
            COMMAND:%1(%2, %3)

you'll need to make something like : (untested)

pawn Код:

#define COMMAND:%1(%2,%3[%4])          \
            forward cmd_%1(%2); \
            public cmd_%1(%2)       \
            new %3[%4];
            
#define CMD:%1(%2,%3[%4]) \
            COMMAND:%1(%2,%3[%4])

#define command(%1,%2,%3) \
            COMMAND:%1(%2, %3)      
      
#define cmd(%1,%2,%3) \
            COMMAND:%1(%2, %3)