Beginning with Sisimai v4.16.0, engine() method is available at Sisimai class. The method provides a feature that returns the list of all the MTA module names and its descriptions like the following example.

Sisimai->engine()

#!/usr/bin/env perl
require Sisimai;
my $v = Sisimai->engine;
print keys %$v;         # 56
for my $e ( keys %$v ) {
    print $e;           # Sisimai::Bite::Email::Exchange2007
    print $v->{ $e };   # Microsoft Exchange Server 2007
}
                

Sisimai.engine()

#!/usr/bin/env ruby
require 'sisimai'
v = Sisimai.engine
puts v.keys.size;  # 56
v.keys.each do |e|
  puts e    # Sisimai::Bite::Email::Exchange2007
  puts v[e] # Microsoft Exchange Server 2007
end