diff --git a/tests/test_plugins/test_sidetag_cli.py b/tests/test_plugins/test_sidetag_cli.py
index 05bc1eda..10c8a756 100644
--- a/tests/test_plugins/test_sidetag_cli.py
+++ b/tests/test_plugins/test_sidetag_cli.py
@@ -21,6 +21,15 @@ def mock_stdout():
     return mock.patch('sys.stdout', new_callable=get_mock)
 
 
+def mock_stderr():
+    def get_mock():
+        if six.PY2:
+            return six.StringIO()
+        else:
+            return io.TextIOWrapper(six.BytesIO())
+    return mock.patch('sys.stderr', new_callable=get_mock)
+
+
 def get_stdout_value(stdout):
     if six.PY2:
         return stdout.getvalue()
@@ -41,14 +50,25 @@ class TestSideTagCLI(unittest.TestCase):
         self.session.getAPIVersion.return_value = koji.API_VERSION
         self.activate_session_mock = mock.patch('koji_cli.commands.activate_session').start()
         self.progname = os.path.basename(sys.argv[0]) or 'koji'
+        self.parser = mock.MagicMock()
 
     def tearDown(self):
         mock.patch.stopall()
 
+    def __vm(self, result):
+        m = koji.VirtualCall('mcall_method', [], {})
+        if isinstance(result, dict) and result.get('faultCode'):
+            m._result = result
+        else:
+            m._result = (result,)
+        return m
+
     @mock_stdout()
     def test_add_sidetag_help(self, stdout):
+        args = ['--help']
+        self.parser.parse_args.return_value = [self.options, args]
         with self.assertRaises(SystemExit) as ex:
-            sidetag.handle_add_sidetag(self.options, self.session, ['--help'])
+            sidetag.handle_add_sidetag(self.options, self.session, args)
         std_output = get_stdout_value(stdout).decode('utf-8')
         expected_help = """Usage: %s add-sidetag [options] <basetag>
 (Specify the --help global option for a list of other help options)
@@ -63,6 +83,71 @@ Options:
         self.assertMultiLineEqual(std_output, expected_help)
         self.assertEqual('0', str(ex.exception))
 
+    @mock_stderr()
+    def test_add_sidetags_without_args(self, stderr):
+        args = []
+        # Run it and check immediate output
+        self.parser.parse_args.return_value = [self.options, args]
+        self.parser.error.side_effect = Exception()
+        with self.assertRaises(SystemExit) as ex:
+            sidetag.handle_add_sidetag(self.options, self.session, args)
+        std_err = get_stdout_value(stderr).decode('utf-8')
+        expected_err = """Usage: %s add-sidetag [options] <basetag>
+(Specify the --help global option for a list of other help options)
+
+%s: error: Only argument is basetag
+""" % (self.progname, self.progname)
+        self.assertEqual(std_err, expected_err)
+        self.assertEqual('2', str(ex.exception))
+        # Finally, assert that things were called as we expected.
+        self.session.createSideTag.assert_not_called()
+
+    @mock_stdout()
+    def test_add_sidetag_valid(self, stdout):
+        args = ['--debuginfo', '--suffix', 'test-suffix', 'sidetag']
+        self.session.createSideTag.return_value = {'name': 'sidetag'}
+        sidetag.handle_add_sidetag(self.options, self.session, args)
+        std_output = get_stdout_value(stdout).decode('utf-8')
+        self.assertEqual(std_output, 'sidetag\n')
+        self.session.createSideTag.assert_called_once_with(
+            'sidetag', debuginfo=True, suffix='test-suffix')
+
+    @mock_stderr()
+    def test_add_sidetags_policy_error(self, stderr):
+        args = ['--debuginfo', '--suffix', 'test-suffix', 'sidetag']
+        self.session.createSideTag.side_effect = koji.ActionNotAllowed("Policy violation")
+        # Run it and check immediate output
+        with self.assertRaises(SystemExit) as ex:
+            sidetag.handle_add_sidetag(self.options, self.session, args)
+        std_err = get_stdout_value(stderr).decode('utf-8')
+        expected_err = """Usage: %s add-sidetag [options] <basetag>
+(Specify the --help global option for a list of other help options)
+
+%s: error: Policy violation
+""" % (self.progname, self.progname)
+        self.assertEqual(std_err, expected_err)
+        self.assertEqual('2', str(ex.exception))
+        self.session.createSideTag.assert_called_once_with(
+            'sidetag', debuginfo=True, suffix='test-suffix')
+
+    @mock_stderr()
+    def test_add_sidetags_old_hub_error(self, stderr):
+        args = ['--debuginfo', '--suffix', 'test-suffix', 'sidetag']
+        self.session.createSideTag.side_effect = koji.ParameterError('suffix')
+        # Run it and check immediate output
+        with self.assertRaises(SystemExit) as ex:
+            sidetag.handle_add_sidetag(self.options, self.session, args)
+        std_err = get_stdout_value(stderr).decode('utf-8')
+        expected_err = """Usage: %s add-sidetag [options] <basetag>
+(Specify the --help global option for a list of other help options)
+
+%s: error: Hub is older and doesn't support --suffix, please run it without it
+""" % (self.progname, self.progname)
+        self.assertEqual(std_err, expected_err)
+        self.assertEqual('2', str(ex.exception))
+        self.session.createSideTag.assert_called_once_with(
+            'sidetag', debuginfo=True, suffix='test-suffix')
+
     @mock_stdout()
     def test_edit_sidetag_help(self, stdout):
         with self.assertRaises(SystemExit) as ex:
@@ -83,6 +168,53 @@ Options:
         self.assertMultiLineEqual(std_output, expected_help)
         self.assertEqual('0', str(ex.exception))
 
+    @mock_stderr()
+    def test_edit_sidetags_with_more_args(self, stderr):
+        args = []
+        # Run it and check immediate output
+        with self.assertRaises(SystemExit) as ex:
+            sidetag.handle_edit_sidetag(self.options, self.session, args)
+        std_err = get_stdout_value(stderr).decode('utf-8')
+        expected_err = """Usage: %s edit-sidetag [options] <sidetag>
+(Specify the --help global option for a list of other help options)
+
+%s: error: Only argument is sidetag
+""" % (self.progname, self.progname)
+        self.assertEqual(std_err, expected_err)
+        self.assertEqual('2', str(ex.exception))
+        # Finally, assert that things were called as we expected.
+        self.session.editSideTag.assert_not_called()
+
+    @mock_stderr()
+    def test_edit_sidetags_without_option(self, stderr):
+        args = ['arg']
+        # Run it and check immediate output
+        with self.assertRaises(SystemExit) as ex:
+            sidetag.handle_edit_sidetag(self.options, self.session, [args])
+        std_err = get_stdout_value(stderr).decode('utf-8')
+        expected_err = """Usage: %s edit-sidetag [options] <sidetag>
+(Specify the --help global option for a list of other help options)
+
+%s: error: At least one option needs to be specified
+""" % (self.progname, self.progname)
+        self.assertEqual(std_err, expected_err)
+        self.assertEqual('2', str(ex.exception))
+        # Finally, assert that things were called as we expected.
+        self.session.editSideTag.assert_not_called()
+
+    @mock_stdout()
+    def test_edit_sidetags_valid(self, stdout):
+        args = ['--debuginfo', '--rpm-macro', 'macroname1=macrovalue1',
+                '--rpm-macro', 'macroname2=macrovalue2', '--remove-rpm-macro', 'macroname3',
+                'sidetag']
+        self.session.editSideTag.return_value = None
+        sidetag.handle_edit_sidetag(self.options, self.session, args)
+        std_output = get_stdout_value(stdout).decode('utf-8')
+        self.assertEqual(std_output, '')
+        self.session.editSideTag.assert_called_once_with(
+            'sidetag', debuginfo=True, remove_rpm_macros=['macroname3'],
+            rpm_macros={'macroname1': 'macrovalue1', 'macroname2': 'macrovalue2'})
+
     @mock_stdout()
     def test_list_sidetags_help(self, stdout):
         with self.assertRaises(SystemExit) as ex:
@@ -100,6 +232,93 @@ Options:
         self.assertMultiLineEqual(std_output, expected_help)
         self.assertEqual('0', str(ex.exception))
 
+    @mock_stderr()
+    def test_list_sidetags_with_args(self, stderr):
+        args = ['arg']
+        # Run it and check immediate output
+        with self.assertRaises(SystemExit) as ex:
+            sidetag.handle_list_sidetags(self.options, self.session, [args])
+        std_err = get_stdout_value(stderr).decode('utf-8')
+        expected_err = """Usage: %s list-sidetags [options]
+(Specify the --help global option for a list of other help options)
+
+%s: error: This command takes no arguments
+""" % (self.progname, self.progname)
+        self.assertEqual(std_err, expected_err)
+        self.assertEqual('2', str(ex.exception))
+        # Finally, assert that things were called as we expected.
+        self.session.getLoggedInUser.assert_not_called()
+        self.session.listSideTags.assert_not_called()
+
+    @mock_stderr()
+    def test_list_sidetags_mine_and_user_option(self, stderr):
+        args = ['--mine', '--user', 'testuser']
+        self.parser.parse_args.return_value = [self.options, args]
+        # Run it and check immediate output
+        with self.assertRaises(SystemExit) as ex:
+            sidetag.handle_list_sidetags(self.options, self.session, args)
+        std_err = get_stdout_value(stderr).decode('utf-8')
+        expected_err = """Usage: %s list-sidetags [options]
+(Specify the --help global option for a list of other help options)
+
+%s: error: Specify only one from --user --mine
+""" % (self.progname, self.progname)
+        self.assertEqual(std_err, expected_err)
+        self.assertEqual('2', str(ex.exception))
+        # Finally, assert that things were called as we expected.
+        self.session.getLoggedInUser.assert_not_called()
+        self.session.listSideTags.assert_not_called()
+
+    @mock_stdout()
+    def test_list_sidetags_mine(self, stdout):
+        expected = """test-tag-sidetag_template-21
+test-tag-sidetag_template-24
+test-tag-sidetag_template-27
+"""
+        self.session.getLoggedInUser.return_value = {'name': 'testuser'}
+        self.session.listSideTags.return_value = [{'id': 21,
+                                                   'name': 'test-tag-sidetag_template-21',
+                                                   'user_id': '1',
+                                                   'user_name': 'testuser'},
+                                                  {'id': 24,
+                                                   'name': 'test-tag-sidetag_template-24',
+                                                   'user_id': '1',
+                                                   'user_name': 'testuser'},
+                                                  {'id': 27,
+                                                   'name': 'test-tag-sidetag_template-27',
+                                                   'user_id': '1',
+                                                   'user_name': 'testuser'}]
+        sidetag.handle_list_sidetags(self.options, self.session, ['--mine'])
+        std_output = get_stdout_value(stdout).decode('utf-8')
+        self.assertMultiLineEqual(std_output, expected)
+        self.session.getLoggedInUser.assert_called_once_with()
+        self.session.listSideTags.assert_called_once_with(basetag=None, user='testuser')
+
+    @mock_stdout()
+    def test_list_sidetags_user(self, stdout):
+        expected = """test-tag-sidetag_template-21
+test-tag-sidetag_template-24
+test-tag-sidetag_template-27
+"""
+        self.session.getLoggedInUser.return_value = {'name': 'testuser'}
+        self.session.listSideTags.return_value = [{'id': 21,
+                                                   'name': 'test-tag-sidetag_template-21',
+                                                   'user_id': '1',
+                                                   'user_name': 'testuser'},
+                                                  {'id': 24,
+                                                   'name': 'test-tag-sidetag_template-24',
+                                                   'user_id': '1',
+                                                   'user_name': 'testuser'},
+                                                  {'id': 27,
+                                                   'name': 'test-tag-sidetag_template-27',
+                                                   'user_id': '1',
+                                                   'user_name': 'testuser'}]
+        sidetag.handle_list_sidetags(self.options, self.session, ['--user', 'testuser'])
+        std_output = get_stdout_value(stdout).decode('utf-8')
+        self.assertMultiLineEqual(std_output, expected)
+        self.session.getLoggedInUser.assert_not_called()
+        self.session.listSideTags.assert_called_once_with(basetag=None, user='testuser')
+
     @mock_stdout()
     def test_remove_sidetag_help(self, stdout):
         with self.assertRaises(SystemExit) as ex:
@@ -113,3 +332,28 @@ Options:
 """ % self.progname
         self.assertMultiLineEqual(std_output, expected_help)
         self.assertEqual('0', str(ex.exception))
+
+    @mock_stderr()
+    def test_remove_sidetag_without_args(self, stderr):
+        args = []
+        # Run it and check immediate output
+        with self.assertRaises(SystemExit) as ex:
+            sidetag.handle_remove_sidetag(self.options, self.session, args)
+        std_err = get_stdout_value(stderr).decode('utf-8')
+        expected_err = """Usage: %s remove-sidetag [options] <sidetag> ...
+(Specify the --help global option for a list of other help options)
+
+%s: error: Sidetag argument is required
+""" % (self.progname, self.progname)
+        self.assertEqual(std_err, expected_err)
+        self.assertEqual('2', str(ex.exception))
+        # Finally, assert that things were called as we expected.
+        self.session.removeSideTag.assert_not_called()
+
+    @mock_stdout()
+    def test_remove_sidetag_valid(self, stdout):
+        mcall = self.session.multicall.return_value.__enter__.return_value
+        mcall.removeSideTag.return_value = self.__vm([None, None])
+        sidetag.handle_remove_sidetag(self.options, self.session, ['sidetag', 'sidetag2'])
+        std_output = get_stdout_value(stdout).decode('utf-8')
+        self.assertMultiLineEqual(std_output, '')