Maybe the following is of use..

Here's an example of a Makefile.PL that helps generate a proper META.yml..

use ExtUtils::MakeMaker;
WriteMakefile(
   NAME => 'WordPress::XMLRPC',
   VERSION_FROM => 'lib/WordPress/XMLRPC.pm',
   PREREQ_PM => {
      'YAML' => 0,
      'SOAP::Lite' => 0,
      'XMLRPC::Lite' => 0,
      'Smart::Comments' => 0,
      'LEOCHARRE::Debug' => 0,
      'LEOCHARRE::CLI2' => 0,
   },
   LICENSE => 'perl',
   AUTHOR => 'Leo Charre leocharre at cpan dot org',
   ABSTRACT_FROM => 'lib/WordPress/XMLRPC.pod',

);
[download]

--- #YAML:1.0
name:               WordPress-XMLRPC
version:            1.21
abstract:           api to wordpress xml rpc calls
author:
    - Leo Charre leocharre at cpan dot org
license:            perl
distribution_type:  module
configure_requires:
    ExtUtils::MakeMaker:  0
requires:
    LEOCHARRE::CLI2:   0
    LEOCHARRE::Debug:  0
    Smart::Comments:   0
    SOAP::Lite:        0
    XMLRPC::Lite:      0
    YAML:              0
no_index:
    directory:
        - t
        - inc
generated_by:       ExtUtils::MakeMaker version 6.48
meta-spec:
    url:      http://module-build.sourceforge.net/META-spec-v1.4.html
    version:  1.4
[download]

You can browse this in the distro WordPress::XMLRPC, also note the pod.

You can check what it's doing via the following.

Once you have your distro,

perl Makefile.PL
make disttest