diff --git a/MANIFEST b/MANIFEST
index e77ce8f..a02184a 100644
--- a/MANIFEST
+++ b/MANIFEST
@@ -71,4 +71,3 @@ t/Net-ACME2-PromiseUtil.t
 t/Net-ACME2-RetryAfter.t
 t/Net-ACME2-revoke.t
 t/Net-ACME2.t
-t/Net-ACME2_pre_rename.t
diff --git a/t/Net-ACME2-Error.t b/t/Net-ACME2-Error.t
index b0bb996..d288e69 100644
--- a/t/Net-ACME2-Error.t
+++ b/t/Net-ACME2-Error.t
@@ -114,4 +114,81 @@ use Net::ACME2::Error ();
     );
 }
 
+# Test type() defaults to 'about:blank' when unset
+{
+    my $err = Net::ACME2::Error->new();
+
+    is(
+        $err->type(),
+        'about:blank',
+        'type() defaults to about:blank',
+    );
+}
+
+# Test description() with known ACME URN types
+{
+    my @known_types = (
+        [ 'badNonce'          => qr/unacceptable anti-replay nonce/ ],
+        [ 'rateLimited'       => qr/rate limit/ ],
+        [ 'unauthorized'      => qr/lacks sufficient authorization/ ],
+        [ 'serverInternal'    => qr/internal error/ ],
+        [ 'malformed'         => qr/malformed/ ],
+        [ 'badCSR'            => qr/unacceptable/ ],
+        [ 'rejectedIdentifier'=> qr/will not issue/ ],
+        [ 'caa'               => qr/CAA/ ],
+        [ 'dns'               => qr/DNS query/ ],
+    );
+
+    for my $t (@known_types) {
+        my ($short_type, $desc_re) = @$t;
+
+        my $err = Net::ACME2::Error->new(
+            type => "urn:ietf:params:acme:error:$short_type",
+        );
+
+        like(
+            $err->description(),
+            $desc_re,
+            "description() for $short_type",
+        );
+    }
+}
+
+# Test description() returns undef for unknown types
+{
+    my $err = Net::ACME2::Error->new(
+        type => 'urn:ietf:params:acme:error:totallyMadeUp',
+    );
+
+    is( $err->description(), undef, 'description() undef for unknown type' );
+}
+
+# Test to_string() includes description for known URN types
+{
+    my $err = Net::ACME2::Error->new(
+        status => 429,
+        type   => 'urn:ietf:params:acme:error:rateLimited',
+        detail => 'too many requests',
+    );
+
+    my $str = $err->to_string();
+
+    like( $str, qr/429/,         'to_string has status' );
+    like( $str, qr/rateLimited/, 'to_string has type' );
+    like( $str, qr/rate limit/,  'to_string has description' );
+    like( $str, qr/too many/,    'to_string has detail' );
+}
+
+# Test subproblems() in list context enforcement
+{
+    my $err = Net::ACME2::Error->new(
+        status => 400,
+        type   => 'urn:ietf:params:acme:error:rejectedIdentifier',
+    );
+
+    # subproblems() requires list context
+    my @subs = $err->subproblems();
+    is( scalar @subs, 0, 'subproblems() returns empty list when none' );
+}
+
 done_testing();
diff --git a/t/Net-ACME2.t b/t/Net-ACME2.t
index 288e1c7..6a5c929 100644
--- a/t/Net-ACME2.t
+++ b/t/Net-ACME2.t
@@ -171,4 +171,27 @@ for my $t (@alg_key) {
     );
 }
 
+# Legacy aliases (create_new_account, create_new_order)
+{
+    my $SERVER_OBJ = Test::ACME2_Server->new(
+        ca_class => 'MyCA',
+    );
+
+    my $acme = MyCA->new( key => $_P256_KEY );
+
+    my $created = $acme->create_new_account(
+        termsOfServiceAgreed => 1,
+    );
+
+    is( $created, 1, 'create_new_account() alias works' );
+
+    my $order = $acme->create_new_order(
+        identifiers => [
+            { type => 'dns', value => 'example.com' },
+        ],
+    );
+
+    isa_ok( $order, 'Net::ACME2::Order', 'create_new_order() alias works' );
+}
+
 done_testing();
diff --git a/t/Net-ACME2_pre_rename.t b/t/Net-ACME2_pre_rename.t
deleted file mode 100644
index 27fab97..0000000
--- a/t/Net-ACME2_pre_rename.t
+++ /dev/null
@@ -1,130 +0,0 @@
-#!/usr/bin/env perl
-
-use strict;
-use warnings;
-
-use Test::More;
-use Test::Exception;
-use Test::FailWarnings;
-
-use Digest::MD5;
-use HTTP::Status;
-use URI;
-use JSON;
-
-use Crypt::Format ();
-
-use FindBin;
-use lib "$FindBin::Bin/lib";
-use Test::ACME2_Server;
-
-#----------------------------------------------------------------------
-
-{
-    package MyCA;
-
-    use parent qw( Net::ACME2 );
-
-    use constant {
-        HOST => 'acme.someca.net',
-        DIRECTORY_PATH => '/acme-directory',
-    };
-}
-
-my $_RSA_KEY  = <<END;
------BEGIN RSA PRIVATE KEY-----
-MIICWwIBAAKBgQCkOYWppsEFfKHqIntkpUjmuwnBH3sRYP00YRdIhrz6ypRpxX6H
-c2Q0IrSprutu9/dUy0j9a96q3kRa9Qxsa7paQj7xtlTWx9qMHvhlrG3eLMIjXT0J
-4+MSCw5LwViZenh0obBWcBbnNYNLaZ9o31DopeKcYOZBMogF6YqHdpIsFQIDAQAB
-AoGAN7RjSFaN5qSN73Ne05bVEZ6kAmQBRLXXbWr5kNpTQ+ZvTSl2b8+OT7jt+xig
-N3XY6WRDD+MFFoRqP0gbvLMV9HiZ4tJ/gTGOHesgyeemY/CBLRjP0mvHOpgADQuA
-+VBZmWpiMRN8tu6xHzKwAxIAfXewpn764v6aXShqbQEGSEkCQQDSh9lbnpB/R9+N
-psqL2+gyn/7bL1+A4MJwiPqjdK3J/Fhk1Yo/UC1266MzpKoK9r7MrnGc0XjvRpMp
-JX8f4MTbAkEAx7FvmEuvsD9li7ylgnPW/SNAswI6P7SBOShHYR7NzT2+FVYd6VtM
-vb1WrhO85QhKgXNjOLLxYW9Uo8s1fNGtzwJAbwK9BQeGT+cZJPsm4DpzpIYi/3Zq
-WG2reWVxK9Fxdgk+nuTOgfYIEyXLJ4cTNrbHAuyU8ciuiRTgshiYgLmncwJAETZx
-KQ51EVsVlKrpFUqI4H72Z7esb6tObC/Vn0B5etR0mwA2SdQN1FkKrKyU3qUNTwU0
-K0H5Xm2rPQcaEC0+rwJAEuvRdNQuB9+vzOW4zVig6HS38bHyJ+qLkQCDWbbwrNlj
-vcVkUrsg027gA5jRttaXMk8x9shFuHB9V5/pkBFwag==
------END RSA PRIVATE KEY-----
-END
-
-my $_P256_KEY = <<END;
------BEGIN EC PRIVATE KEY-----
-MHcCAQEEIKDv8TBijBVbTYB7lfUnwLn4qjqWD0GD7XOXzdp0wb61oAoGCCqGSM49
-AwEHoUQDQgAEBJIULcFadtIBc0TuNzT80UFcfkQ0U7+EPqEJNXamG1H4/z8xVgE7
-3hoBfX4xbN2Hx2p26eNIptt+1jj2H/M44g==
------END EC PRIVATE KEY-----
-END
-
-my $_P384_KEY = <<END;
------BEGIN EC PRIVATE KEY-----
-MIGkAgEBBDBqmQFgqovKRpzWs0JST9p/vtRQCHQi3r+6N2zoOorRv/JQoGMHZB+i
-c4d7oLnMpx+gBwYFK4EEACKhZANiAATXy7Zwmz5s98iSrQ+Y6lZ56g8/1INa4GY2
-LeDDedG+NvKKcj0P3uJV994RSyitrijBQvN2ccSuL67IHUQ3I4O7S7eKRNsU8R7K
-3ljffUl1vtb6GnjPgSZgt2zugJCwlH8=
------END EC PRIVATE KEY-----
-END
-
-my @alg_key = (
-    [ rsa => $_RSA_KEY ],
-    [ p256 => $_P256_KEY ],
-    [ p384 => $_P384_KEY ],
-);
-
-for my $t (@alg_key) {
-    my ($alg, $key_pem) = @$t;
-
-    my $key_der = Crypt::Format::pem2der($key_pem);
-
-    my @formats = (
-        [ pem => $key_pem ],
-        [ der => $key_der ],
-    );
-
-    for my $tt (@formats) {
-        my ($format, $key_str) = @$tt;
-
-        diag "$alg, $format";
-
-        lives_ok(
-            sub {
-                my $SERVER_OBJ = Test::ACME2_Server->new(
-                    ca_class => 'MyCA',
-                );
-
-                #----------------------------------------------------------------------
-                # new()
-
-                my $acme = MyCA->new( key => $key_str );
-                isa_ok( $acme, 'MyCA', 'new() response' );
-
-                #----------------------------------------------------------------------
-                # get_terms_of_service()
-
-                my $tos = $acme->get_terms_of_service();
-
-                is( $tos, $SERVER_OBJ->TOS_URL(), 'get_terms_of_service' );
-
-                #----------------------------------------------------------------------
-
-                my $created = $acme->create_account(
-                    termsOfServiceAgreed => 1,
-                );
-
-                is( $created, 1, 'create_account() on new account creation' );
-
-                my $key_id = $acme->key_id();
-                ok( $key_id, 'key_id() gets updated' );
-
-                $created = $acme->create_account();
-                is( $created, 0, 'create_account() if account already exists' );
-
-                is( $acme->key_id(), $key_id, 'key_id() stays the same' );
-            },
-            "no errors: $alg, $format",
-        );
-    }
-}
-
-done_testing();