Hi!
I'm working on Hibernate OGM which is a JPA wrapper for NoSQL database.
We support the shell syntax for queries and we have users asking for NumberInt support, which is at least partially supported in the server but not at all in the Java driver.
A pull request will follow adding the NumberInt/$numberInt support to the JsonReader.
Note that, for the JsonWriter, it's not implemented as it has consequences on timestamp and so on. AFAICS, judging by the open tickets, the server has the very same behavior.