diff --git a/tempest/api/compute/admin/test_aggregates_negative.py b/tempest/api/compute/admin/test_aggregates_negative.py
index a6e0efa..d5adfed 100644
--- a/tempest/api/compute/admin/test_aggregates_negative.py
+++ b/tempest/api/compute/admin/test_aggregates_negative.py
@@ -144,6 +144,7 @@
     @decorators.attr(type=['negative'])
     @decorators.idempotent_id('19dd44e1-c435-4ee1-a402-88c4f90b5950')
     def test_aggregate_add_existent_host(self):
+        # Adding already existing host to aggregate should fail.
         self.useFixture(fixtures.LockFixture('availability_zone'))
         aggregate = self._create_test_aggregate()
 
@@ -172,6 +173,7 @@
     @decorators.attr(type=['negative'])
     @decorators.idempotent_id('95d6a6fa-8da9-4426-84d0-eec0329f2e4d')
     def test_aggregate_remove_nonexistent_host(self):
+        # Removing not existing host from aggregate should fail.
         aggregate = self._create_test_aggregate()
 
         self.assertRaises(lib_exc.NotFound, self.client.remove_host,
diff --git a/tempest/api/compute/admin/test_hosts.py b/tempest/api/compute/admin/test_hosts.py
index c246685..31fe2b5 100644
--- a/tempest/api/compute/admin/test_hosts.py
+++ b/tempest/api/compute/admin/test_hosts.py
@@ -29,11 +29,13 @@
 
     @decorators.idempotent_id('9bfaf98d-e2cb-44b0-a07e-2558b2821e4f')
     def test_list_hosts(self):
+        # Listing hosts.
         hosts = self.client.list_hosts()['hosts']
         self.assertGreaterEqual(len(hosts), 2, str(hosts))
 
     @decorators.idempotent_id('5dc06f5b-d887-47a2-bb2a-67762ef3c6de')
     def test_list_hosts_with_zone(self):
+        # Listing hosts with specified availability zone
         self.useFixture(fixtures.LockFixture('availability_zone'))
         hosts = self.client.list_hosts()['hosts']
         host = hosts[0]
@@ -43,6 +45,7 @@
 
     @decorators.idempotent_id('9af3c171-fbf4-4150-a624-22109733c2a6')
     def test_list_hosts_with_a_blank_zone(self):
+        # Listing hosts with blank availability zone.
         # If send the request with a blank zone, the request will be successful
         # and it will return all the hosts list
         hosts = self.client.list_hosts(zone='')['hosts']
@@ -50,6 +53,7 @@
 
     @decorators.idempotent_id('c6ddbadb-c94e-4500-b12f-8ffc43843ff8')
     def test_list_hosts_with_nonexistent_zone(self):
+        # Listing hosts with not existing availability zone.
         # If send the request with a nonexistent zone, the request will be
         # successful and no hosts will be returned
         hosts = self.client.list_hosts(zone='xxx')['hosts']
@@ -57,6 +61,7 @@
 
     @decorators.idempotent_id('38adbb12-aee2-4498-8aec-329c72423aa4')
     def test_show_host_detail(self):
+        # Showing host details.
         hosts = self.client.list_hosts()['hosts']
 
         hosts = [host for host in hosts if host['service'] == 'compute']
diff --git a/tempest/api/compute/admin/test_hosts_negative.py b/tempest/api/compute/admin/test_hosts_negative.py
index 8a91ae2..e8733c8 100644
--- a/tempest/api/compute/admin/test_hosts_negative.py
+++ b/tempest/api/compute/admin/test_hosts_negative.py
@@ -39,18 +39,21 @@
     @decorators.attr(type=['negative'])
     @decorators.idempotent_id('dd032027-0210-4d9c-860e-69b1b8deed5f')
     def test_list_hosts_with_non_admin_user(self):
+        # Non admin user is not allowed to list hosts.
         self.assertRaises(lib_exc.Forbidden,
                           self.non_admin_client.list_hosts)
 
     @decorators.attr(type=['negative'])
     @decorators.idempotent_id('e75b0a1a-041f-47a1-8b4a-b72a6ff36d3f')
     def test_show_host_detail_with_nonexistent_hostname(self):
+        # Showing host detail with not existing hostname should fail.
         self.assertRaises(lib_exc.NotFound,
                           self.client.show_host, 'nonexistent_hostname')
 
     @decorators.attr(type=['negative'])
     @decorators.idempotent_id('19ebe09c-bfd4-4b7c-81a2-e2e0710f59cc')
     def test_show_host_detail_with_non_admin_user(self):
+        # Non admin user is not allowed to show host details.
         self.assertRaises(lib_exc.Forbidden,
                           self.non_admin_client.show_host,
                           self.hostname)
@@ -58,6 +61,7 @@
     @decorators.attr(type=['negative'])
     @decorators.idempotent_id('e40c72b1-0239-4ed6-ba21-81a184df1f7c')
     def test_update_host_with_non_admin_user(self):
+        # Non admin user is not allowed to update host.
         self.assertRaises(lib_exc.Forbidden,
                           self.non_admin_client.update_host,
                           self.hostname,
@@ -67,7 +71,8 @@
     @decorators.attr(type=['negative'])
     @decorators.idempotent_id('fbe2bf3e-3246-4a95-a59f-94e4e298ec77')
     def test_update_host_with_invalid_status(self):
-        # 'status' can only be 'enable' or 'disable'
+        # Updating host to invalid status should fail,
+        # 'status' can only be 'enable' or 'disable'.
         self.assertRaises(lib_exc.BadRequest,
                           self.client.update_host,
                           self.hostname,
@@ -77,7 +82,8 @@
     @decorators.attr(type=['negative'])
     @decorators.idempotent_id('ab1e230e-5e22-41a9-8699-82b9947915d4')
     def test_update_host_with_invalid_maintenance_mode(self):
-        # 'maintenance_mode' can only be 'enable' or 'disable'
+        # Updating host to invalid maintenance mode should fail,
+        # 'maintenance_mode' can only be 'enable' or 'disable'.
         self.assertRaises(lib_exc.BadRequest,
                           self.client.update_host,
                           self.hostname,
@@ -87,7 +93,8 @@
     @decorators.attr(type=['negative'])
     @decorators.idempotent_id('0cd85f75-6992-4a4a-b1bd-d11e37fd0eee')
     def test_update_host_without_param(self):
-        # 'status' or 'maintenance_mode' needed for host update
+        # Updating host without param should fail,
+        # 'status' or 'maintenance_mode' is needed for host update.
         self.assertRaises(lib_exc.BadRequest,
                           self.client.update_host,
                           self.hostname)
@@ -95,6 +102,7 @@
     @decorators.attr(type=['negative'])
     @decorators.idempotent_id('23c92146-2100-4d68-b2d6-c7ade970c9c1')
     def test_update_nonexistent_host(self):
+        # Updating not existing host should fail.
         self.assertRaises(lib_exc.NotFound,
                           self.client.update_host,
                           'nonexistent_hostname',
@@ -104,6 +112,7 @@
     @decorators.attr(type=['negative'])
     @decorators.idempotent_id('0d981ac3-4320-4898-b674-82b61fbb60e4')
     def test_startup_nonexistent_host(self):
+        # Starting up not existing host should fail.
         self.assertRaises(lib_exc.NotFound,
                           self.client.startup_host,
                           'nonexistent_hostname')
@@ -111,6 +120,7 @@
     @decorators.attr(type=['negative'])
     @decorators.idempotent_id('9f4ebb7e-b2ae-4e5b-a38f-0fd1bb0ddfca')
     def test_startup_host_with_non_admin_user(self):
+        # Non admin user is not allowed to startup host.
         self.assertRaises(lib_exc.Forbidden,
                           self.non_admin_client.startup_host,
                           self.hostname)
@@ -118,6 +128,7 @@
     @decorators.attr(type=['negative'])
     @decorators.idempotent_id('9e637444-29cf-4244-88c8-831ae82c31b6')
     def test_shutdown_nonexistent_host(self):
+        # Shutting down not existing host should fail.
         self.assertRaises(lib_exc.NotFound,
                           self.client.shutdown_host,
                           'nonexistent_hostname')
@@ -125,6 +136,7 @@
     @decorators.attr(type=['negative'])
     @decorators.idempotent_id('a803529c-7e3f-4d3c-a7d6-8e1c203d27f6')
     def test_shutdown_host_with_non_admin_user(self):
+        # Non admin user is not allowed to shutdown host.
         self.assertRaises(lib_exc.Forbidden,
                           self.non_admin_client.shutdown_host,
                           self.hostname)
@@ -132,6 +144,7 @@
     @decorators.attr(type=['negative'])
     @decorators.idempotent_id('f86bfd7b-0b13-4849-ae29-0322e83ee58b')
     def test_reboot_nonexistent_host(self):
+        # Rebooting not existing host should fail.
         self.assertRaises(lib_exc.NotFound,
                           self.client.reboot_host,
                           'nonexistent_hostname')
@@ -139,6 +152,7 @@
     @decorators.attr(type=['negative'])
     @decorators.idempotent_id('02d79bb9-eb57-4612-abf6-2cb38897d2f8')
     def test_reboot_host_with_non_admin_user(self):
+        # Non admin user is not allowed to reboot host.
         self.assertRaises(lib_exc.Forbidden,
                           self.non_admin_client.reboot_host,
                           self.hostname)
diff --git a/tempest/api/compute/admin/test_hypervisor.py b/tempest/api/compute/admin/test_hypervisor.py
index 9822c26..e45aac5 100644
--- a/tempest/api/compute/admin/test_hypervisor.py
+++ b/tempest/api/compute/admin/test_hypervisor.py
@@ -134,6 +134,7 @@
 
     @decorators.idempotent_id('d7e1805b-3b14-4a3b-b6fd-50ec6d9f361f')
     def test_search_hypervisor(self):
+        # Searching for hypervisors by its name.
         hypers = self._list_hypervisors()
         self.assertNotEmpty(hypers, "No hypervisors found.")
         hypers = self.client.search_hypervisor(
diff --git a/tempest/api/compute/admin/test_hypervisor_negative.py b/tempest/api/compute/admin/test_hypervisor_negative.py
index 0056376..723b93c 100644
--- a/tempest/api/compute/admin/test_hypervisor_negative.py
+++ b/tempest/api/compute/admin/test_hypervisor_negative.py
@@ -40,8 +40,8 @@
     @decorators.attr(type=['negative'])
     @decorators.idempotent_id('c136086a-0f67-4b2b-bc61-8482bd68989f')
     def test_show_nonexistent_hypervisor(self):
+        # Showing not existing hypervisor should fail.
         nonexistent_hypervisor_id = data_utils.rand_uuid()
-
         self.assertRaises(
             lib_exc.NotFound,
             self.client.show_hypervisor,
@@ -50,6 +50,7 @@
     @decorators.attr(type=['negative'])
     @decorators.idempotent_id('51e663d0-6b89-4817-a465-20aca0667d03')
     def test_show_hypervisor_with_non_admin_user(self):
+        # Non admin user is not allowed to show hypervisor.
         hypers = self._list_hypervisors()
         self.assertNotEmpty(hypers)
 
@@ -61,6 +62,7 @@
     @decorators.attr(type=['negative'])
     @decorators.idempotent_id('e2b061bb-13f9-40d8-9d6e-d5bf17595849')
     def test_get_hypervisor_stats_with_non_admin_user(self):
+        # Non admin user is not allowed to get hypervisor stats.
         self.assertRaises(
             lib_exc.Forbidden,
             self.non_adm_client.show_hypervisor_statistics)
@@ -68,6 +70,7 @@
     @decorators.attr(type=['negative'])
     @decorators.idempotent_id('f60aa680-9a3a-4c7d-90e1-fae3a4891303')
     def test_get_nonexistent_hypervisor_uptime(self):
+        # Getting uptime of not existing hypervisor should fail.
         nonexistent_hypervisor_id = data_utils.rand_uuid()
 
         self.assertRaises(
@@ -78,6 +81,7 @@
     @decorators.attr(type=['negative'])
     @decorators.idempotent_id('6c3461f9-c04c-4e2a-bebb-71dc9cb47df2')
     def test_get_hypervisor_uptime_with_non_admin_user(self):
+        # Non admin user is not allowed to get hypervisor uptime.
         hypers = self._list_hypervisors()
         self.assertNotEmpty(hypers)
 
@@ -97,7 +101,7 @@
     @decorators.attr(type=['negative'])
     @decorators.idempotent_id('dc02db05-e801-4c5f-bc8e-d915290ab345')
     def test_get_hypervisor_list_details_with_non_admin_user(self):
-        # List of hypervisor details and available services with non admin user
+        # Non admin user is not allowed to list hypervisor details.
         self.assertRaises(
             lib_exc.Forbidden,
             self.non_adm_client.list_hypervisors, detail=True)
@@ -109,6 +113,7 @@
     @decorators.attr(type=['negative'])
     @decorators.idempotent_id('2a0a3938-832e-4859-95bf-1c57c236b924')
     def test_show_servers_with_non_admin_user(self):
+        # Non admin user is not allowed to show servers on hypervisor.
         hypers = self._list_hypervisors()
         self.assertNotEmpty(hypers)
 
@@ -120,6 +125,7 @@
     @decorators.attr(type=['negative'])
     @decorators.idempotent_id('02463d69-0ace-4d33-a4a8-93d7883a2bba')
     def test_show_servers_with_nonexistent_hypervisor(self):
+        # Showing servers on not existing hypervisor should fail.
         nonexistent_hypervisor_id = data_utils.rand_uuid()
 
         self.assertRaises(
@@ -130,6 +136,7 @@
     @decorators.attr(type=['negative'])
     @decorators.idempotent_id('5b6a6c79-5dc1-4fa5-9c58-9c8085948e74')
     def test_search_hypervisor_with_non_admin_user(self):
+        # Non admin user is not allowed to search hypervisor.
         hypers = self._list_hypervisors()
         self.assertNotEmpty(hypers)
 
@@ -141,6 +148,7 @@
     @decorators.attr(type=['negative'])
     @decorators.idempotent_id('19a45cc1-1000-4055-b6d2-28e8b2ec4faa')
     def test_search_nonexistent_hypervisor(self):
+        # Searching not existing hypervisor should fail.
         self.assertRaises(
             lib_exc.NotFound,
             self.client.search_hypervisor,
diff --git a/tempest/api/compute/admin/test_services.py b/tempest/api/compute/admin/test_services.py
index 73e191b..bf846e5 100644
--- a/tempest/api/compute/admin/test_services.py
+++ b/tempest/api/compute/admin/test_services.py
@@ -28,11 +28,13 @@
 
     @decorators.idempotent_id('5be41ef4-53d1-41cc-8839-5c2a48a1b283')
     def test_list_services(self):
+        # Listing nova services
         services = self.client.list_services()['services']
         self.assertNotEmpty(services)
 
     @decorators.idempotent_id('f345b1ec-bc6e-4c38-a527-3ca2bc00bef5')
     def test_get_service_by_service_binary_name(self):
+        # Listing nova services by binary name.
         binary_name = 'nova-compute'
         services = self.client.list_services(binary=binary_name)['services']
         self.assertNotEmpty(services)
@@ -41,6 +43,7 @@
 
     @decorators.idempotent_id('affb42d5-5b4b-43c8-8b0b-6dca054abcca')
     def test_get_service_by_host_name(self):
+        # Listing nova services by host name.
         services = self.client.list_services()['services']
         host_name = services[0]['host']
         services_on_host = [service for service in services if
diff --git a/tempest/api/compute/servers/test_multiple_create.py b/tempest/api/compute/servers/test_multiple_create.py
index e176251..dcadace 100644
--- a/tempest/api/compute/servers/test_multiple_create.py
+++ b/tempest/api/compute/servers/test_multiple_create.py
@@ -23,6 +23,7 @@
 
     @decorators.idempotent_id('61e03386-89c3-449c-9bb1-a06f423fd9d1')
     def test_multiple_create(self):
+        # Creating server with min_count=2, 2 servers will be created.
         tenant_network = self.get_tenant_network()
         body, servers = compute.create_test_server(
             self.os_primary,
@@ -39,6 +40,8 @@
 
     @decorators.idempotent_id('864777fb-2f1e-44e3-b5b9-3eb6fa84f2f7')
     def test_multiple_create_with_reservation_return(self):
+        # Creating multiple servers with return_reservation_id=True,
+        # reservation_id will be returned.
         body = self.create_test_server(wait_until='ACTIVE',
                                        min_count=1,
                                        max_count=2,
diff --git a/tempest/api/compute/servers/test_multiple_create_negative.py b/tempest/api/compute/servers/test_multiple_create_negative.py
index 422510f..6bdf83b 100644
--- a/tempest/api/compute/servers/test_multiple_create_negative.py
+++ b/tempest/api/compute/servers/test_multiple_create_negative.py
@@ -23,6 +23,7 @@
     @decorators.attr(type=['negative'])
     @decorators.idempotent_id('daf29d8d-e928-4a01-9a8c-b129603f3fc0')
     def test_min_count_less_than_one(self):
+        # Creating server with min_count=0 should fail.
         invalid_min_count = 0
         self.assertRaises(lib_exc.BadRequest, self.create_test_server,
                           min_count=invalid_min_count)
@@ -30,6 +31,7 @@
     @decorators.attr(type=['negative'])
     @decorators.idempotent_id('999aa722-d624-4423-b813-0d1ac9884d7a')
     def test_min_count_non_integer(self):
+        # Creating server with non-integer min_count should fail.
         invalid_min_count = 2.5
         self.assertRaises(lib_exc.BadRequest, self.create_test_server,
                           min_count=invalid_min_count)
@@ -37,6 +39,7 @@
     @decorators.attr(type=['negative'])
     @decorators.idempotent_id('a6f9c2ab-e060-4b82-b23c-4532cb9390ff')
     def test_max_count_less_than_one(self):
+        # Creating server with max_count < 1 shoudld fail.
         invalid_max_count = 0
         self.assertRaises(lib_exc.BadRequest, self.create_test_server,
                           max_count=invalid_max_count)
@@ -44,6 +47,7 @@
     @decorators.attr(type=['negative'])
     @decorators.idempotent_id('9c5698d1-d7af-4c80-b971-9d403135eea2')
     def test_max_count_non_integer(self):
+        # Creating server with non-integer max_count should fail.
         invalid_max_count = 2.5
         self.assertRaises(lib_exc.BadRequest, self.create_test_server,
                           max_count=invalid_max_count)
@@ -51,6 +55,7 @@
     @decorators.attr(type=['negative'])
     @decorators.idempotent_id('476da616-f1ef-4271-a9b1-b9fc87727cdf')
     def test_max_count_less_than_min_count(self):
+        # Creating server with max_count less than min_count should fail.
         min_count = 3
         max_count = 2
         self.assertRaises(lib_exc.BadRequest, self.create_test_server,