I'd try

 $url = URI->new("https://somesite.com/foo/bar");
 $url->query_form( 
        jsessionid => $jsessionId,
        requestor => 'AGE',
        doctype => 'Statement',
        docid => $docid,
        token => $token,
    ); 
 
 $response = $agent->get($url);
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