TL;DR.What are you trying to do? My best guess is serializing with JSON a list of actions, and running them from the deserialized JSON, but I'm not sure. Probably Scala reflection (or its next generation in scala.meta) is the answer, which avoids caring about details such as this or tons of other ones.
In that tuple
Int is boxed. I'm not sure why you get
Object instead of
java.lang.Int (others might know), but it's somewhat sensible. But regardless of that, I expect you're not really supposed to rely on such details (they're not documented and subject to change), and you should usually use Scala reflection, which reads extra info in classfiles which preserves the Scala signatures. Otherwise, you're liable to run into many other issues on any nontrivial examples.