はい，そういうことです．
といっても俺も特に意識してなかったけど．OUTPUTにしておけば，XSS対策でタブのエスケープとかしてくれるらしい．
APIだし，TYPE_STRING のほうがいいかも？

<pre>
As you can see above, the $this->getParam() method is not bound to a specific method type. Moreover, as noted above, there are many different types that parameters can be casted as — that's the second parameter

Integer: self::TYPE_INT, self::TYPE_INTEGER, self::TYPE_LONG
Double: self::TYPE_DOUBLE
Float: self::TYPE_FLOAT
Boolean: self::TYPE_BOOLEAN
String: self::TYPE_STRING
Array: self::TYPE_ARRAY
Safe Output (htmlentities): self::TYPE_OUTPUT
File: self::TYPE_FILE
</pre>
http://frapi.github.com/developing/coding-actions.html