Provide a short description in the NAME section of the pod (after the module name followed by a hyphen) at least for the main module of this distribution.
Take a look at the META.yml Spec at http://module-build.sourceforge.net/META-spec-v1.4.html (for version 1.4) or http://search.cpan.org/perldoc?CPAN::Meta::Spec (for version 2), and change your META.yml accordingly.
Error: Missing mandatory field, 'abstract' (abstract) [Validation: 1.4];value is an undefined string (abstract) [Validation: 1.4]
Add a META.json to the distribution. Your buildtool should be able to autogenerate it.
This is not a critical issue. Currently mainly informative for the CPANTS authors. It might be removed later.
Add all modules contained in this distribution to the META.yml field 'provides'. Module::Build or Dist::Zilla::Plugin::MetaProvides do this automatically for you.