JSON Array
When sending requests to the API and your asked to provide a raw JSON Array, you must provide the data requested as a JSON Array.
For instance if you were setting the testers for your pack and had 2 users, TestUser1 and TestUser2 you would send the request as below:
[ "TestUser1", "TestUser2" ]
You can send it like below if you want it easier to format:
[ "TestUser1", "TestUser2" ]
But be careful to not include a closing comma otherwise the request will return invalid:
[ "TestUser1", "TestUser2", <-- WRONG ]