You need to check the cmd_access
PHP Code:
if(!cmd_access(id,level,cid,2)) // the 4th parameter is the number of argc (number of blanks)
And ....
if(!equali(arg_name,"@ALL")) target = cmd_target(id,arg_name,0)
else target = 1
And...
if(equali(arg_name,"@ALL"))
{
for(new i=1;i<=get_maxplayers();i++) if(is_user_connected(i)) zp_ammopacks_set(i, zp_ammopacks_get(i) + num_ap)
client_printc(0, "!g%s %L", PREFIX, LANG_PLAYER, "AP_AMMOTOALL", name, num_ap)
}