Try this one:
Syntax: $rbkx(text or %variable here)
Example: $rbkx([1] ]2[ ]3[)

 alias rbkx { return $regsubex($1-,/(\[[^\s].*?\])/ig,$null) } 

Simple is the keyword. You don't need any registrations or API keys. Just load the script and it should work in any channel your bot is in.Important: mIRC v7.56+ is required, because of $urlget function.