HTTP::Throwable provides a set of strongly-typed, PSGI-friendly exception
implementations corresponding to the HTTP error status code (4xx-5xx) as well as
the redirection codes (3xx).

This particular package (HTTP::Throwable) is the shared role for all the
exceptions involved. It's not intended that you use HTTP::Throwable directly,
although you can, and instructions for using it correctly are given below.
Instead, you probably want to use HTTP::Throwable::Factory, which will assemble
exception classes from roles needed to build an exception for your use case.