Data::Processor is pretty close to what you describe. Though I think you might find Types::Standard does what you want in a slightly different way.

use Types::Standard -types;

my $state = StrMatch[qr/^[A-Z]{2}$/];
my $token = Str->where(sub { $database->check_valid_token($_) });
my $thing = Dict[token => $token, state => ArrayRef[$state]];

if ($thing->check($data)) {
   ...;
}
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