Steps to reproduce

Create a survey with some participants, some of which are used and some of which are unused. Call the list_participants function with bUnused having the following values:
1) Not supplied at all
2) explicit false (default value according to the documentation)
3) explicit true

Expected result

1) Returns only used tokens
2) Identical as 1) because according to the docs false is the default value
3) Not entirely clear, but i would assume that it would return all tokens, used AND unused.

I also expect the documentation to reflect this behavior clearly and correctly.

Actual result

1) Returns only UNUSED tokens
2) Returns ALL tokens, used and unused
3) Returns only UNUSED tokens

The documentation is unclear and does not reflect the actual functionality. The default value as documented seems to be wrong, and the value of the property seems to do the exact oposite as the naming suggests.