There are a number of inconsistencies in parameter naming e.g. penv vs. p_env, and vm vs p_vm, that should be made consistent across the invocation API. Some grammatical improvements in parameter descriptions can also be made e.g.

`vm`: the VM to which the current thread will be attached, must not be `NULL`.

should read:

`vm`: the VM to which the current thread will be attached. It must not be `NULL`.