i don't understand why the halt at the end?
also maybe add a lil flood pro to it

on $@*:text:/^!clear$/iS:#:{   
  if (!%f) { inc -u5 %f
    if ($nick(#,$nick,vr)) { .notice $nick you must be a mod to use this command }
    else {
      msg # /clear 
      msg # $nick Has Cleared the chatroom!
    }
  } 
}