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: License 'http://dev.perl.org/licenses/' is invalid (license) [Validation: 1.4]
List all used modules in META.yml requires
Add 'use strict' (or its equivalents) to all modules, or convince us that your favorite module is well-known enough and people can easily see the modules are strictly written.
Add a META.json to the distribution. Your buildtool should be able to autogenerate it.
Add 'use warnings' (or its equivalents) to all modules (this will require perl > 5.6), or convince us that your favorite module is well-known enough and people can easily see the modules warn when something bad happens.
List all modules used in the test suite in META.yml build_requires
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.
|CatalystX::Controller::OpenSearch||controller for Search::OpenSearch::Server::Catalyst||metacpan|
|Search::OpenSearch::Result||REST action response||0.301||metacpan|
|Search::OpenSearch::Server||serve OpenSearch results||0.301||metacpan|
|Search::OpenSearch::Server::Catalyst||serve OpenSearch results with Catalyst||0.301||metacpan|
|Search::OpenSearch::Server::Plack||serve OpenSearch results with Plack||0.301||metacpan|