diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 5b37da0..118c153 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -1,6 +1,10 @@
 name: Tests
 
-on: [push, pull_request]
+on:
+  pull_request:
+  push:
+    branches:
+      - "master"
 
 jobs:
   PHPStan:
@@ -39,7 +43,7 @@ jobs:
       - name: PHPStan tests
         run: vendor/bin/phpstan analyze -l 8 -a vendor/yiisoft/yii2/Yii.php --no-progress src
 
-  PHPUnit:
+  Infection:
     name: PHP ${{ matrix.php }}
     runs-on: ubuntu-latest
     strategy:
@@ -56,7 +60,7 @@ jobs:
         with:
           php-version: ${{ matrix.php }}
           extensions: mbstring, intl, mysql
-          coverage: none
+          coverage: "pcov"
         env:
           COMPOSER_TOKEN: ${{ secrets.GITHUB_TOKEN }}
           update: true
@@ -80,5 +84,13 @@ jobs:
         if: matrix.php == '7.4'
         run: composer update --prefer-dist --no-interaction --no-progress --optimize-autoloader
 
-      - name: PHPUnit tests
-        run: vendor/bin/phpunit --verbose
+      - name: Run PHPUnit
+        if: matrix.php == '8.0'
+        run: vendor/bin/phpunit
+
+      - name: Run Infection with PHPUnit
+        if: matrix.php == '7.4'
+        run: |
+          mkdir -p build/logs
+          vendor/bin/phpunit --coverage-xml=build/logs/coverage-xml --log-junit=build/logs/junit.xml
+          vendor/bin/infection --threads=2 --coverage=build/logs --show-mutations --no-progress
diff --git a/README.md b/README.md
index e050a73..9779e67 100644
--- a/README.md
+++ b/README.md
@@ -14,7 +14,4 @@ There are some rules:
  - each repository knows how to handle one single storage unit and not more,
  - components operate on repositories, not on identifiers.
 
-TODOs:
- - [ ] Infection
-
 When API is ready, I'll start preparing the client.
diff --git a/infection.json.dist b/infection.json.dist
index bfd12da..c79a010 100644
--- a/infection.json.dist
+++ b/infection.json.dist
@@ -10,6 +10,6 @@
     "mutators": {
         "@default": true
     },
-    "minMsi": 95,
+    "minMsi": 100,
     "minCoveredMsi": 100
 }
diff --git a/phpunit.xml b/phpunit.xml.dist
similarity index 100%
rename from phpunit.xml
rename to phpunit.xml.dist
diff --git a/src/Services/Category/CategoryArchiver.php b/src/Services/Category/CategoryArchiver.php
index ae770b0..1fcc102 100644
--- a/src/Services/Category/CategoryArchiver.php
+++ b/src/Services/Category/CategoryArchiver.php
@@ -4,6 +4,7 @@
 
 namespace Podium\Api\Services\Category;
 
+use InvalidArgumentException;
 use Podium\Api\Components\PodiumResponse;
 use Podium\Api\Events\ArchiveEvent;
 use Podium\Api\Interfaces\ArchiverInterface;
@@ -38,7 +39,17 @@ private function beforeArchive(): bool
      */
     public function archive(RepositoryInterface $category): PodiumResponse
     {
-        if (!$category instanceof CategoryRepositoryInterface || !$this->beforeArchive()) {
+        if (!$category instanceof CategoryRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Category must be instance of Podium\Api\Interfaces\CategoryRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$this->beforeArchive()) {
             return PodiumResponse::error();
         }
 
@@ -94,7 +105,17 @@ private function beforeRevive(): bool
      */
     public function revive(RepositoryInterface $category): PodiumResponse
     {
-        if (!$category instanceof CategoryRepositoryInterface || !$this->beforeRevive()) {
+        if (!$category instanceof CategoryRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Category must be instance of Podium\Api\Interfaces\CategoryRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$this->beforeRevive()) {
             return PodiumResponse::error();
         }
 
diff --git a/src/Services/Category/CategoryRemover.php b/src/Services/Category/CategoryRemover.php
index ba944fa..3c15b1a 100644
--- a/src/Services/Category/CategoryRemover.php
+++ b/src/Services/Category/CategoryRemover.php
@@ -4,6 +4,7 @@
 
 namespace Podium\Api\Services\Category;
 
+use InvalidArgumentException;
 use Podium\Api\Components\PodiumResponse;
 use Podium\Api\Events\RemoveEvent;
 use Podium\Api\Interfaces\CategoryRepositoryInterface;
@@ -36,7 +37,17 @@ private function beforeRemove(): bool
      */
     public function remove(RepositoryInterface $category): PodiumResponse
     {
-        if (!$category instanceof CategoryRepositoryInterface || !$this->beforeRemove()) {
+        if (!$category instanceof CategoryRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Category must be instance of Podium\Api\Interfaces\CategoryRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$this->beforeRemove()) {
             return PodiumResponse::error();
         }
 
diff --git a/src/Services/Category/CategorySorter.php b/src/Services/Category/CategorySorter.php
index 4f87e82..77a60d1 100644
--- a/src/Services/Category/CategorySorter.php
+++ b/src/Services/Category/CategorySorter.php
@@ -4,6 +4,7 @@
 
 namespace Podium\Api\Services\Category;
 
+use InvalidArgumentException;
 use Podium\Api\Components\PodiumResponse;
 use Podium\Api\Events\SortEvent;
 use Podium\Api\Interfaces\CategoryRepositoryInterface;
@@ -39,11 +40,27 @@ private function beforeReplace(): bool
      */
     public function replace(RepositoryInterface $firstCategory, RepositoryInterface $secondCategory): PodiumResponse
     {
-        if (
-            !$firstCategory instanceof CategoryRepositoryInterface
-            || !$secondCategory instanceof CategoryRepositoryInterface
-            || !$this->beforeReplace()
-        ) {
+        if (!$firstCategory instanceof CategoryRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'First category must be instance of Podium\Api\Interfaces\CategoryRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$secondCategory instanceof CategoryRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Second category must be instance of Podium\Api\Interfaces\CategoryRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$this->beforeReplace()) {
             return PodiumResponse::error();
         }
 
@@ -98,7 +115,17 @@ private function beforeSort(): bool
      */
     public function sort(RepositoryInterface $category): PodiumResponse
     {
-        if (!$category instanceof CategoryRepositoryInterface || !$this->beforeSort()) {
+        if (!$category instanceof CategoryRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Category must be instance of Podium\Api\Interfaces\CategoryRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$this->beforeSort()) {
             return PodiumResponse::error();
         }
 
diff --git a/src/Services/Forum/ForumArchiver.php b/src/Services/Forum/ForumArchiver.php
index b50d448..bfca34b 100644
--- a/src/Services/Forum/ForumArchiver.php
+++ b/src/Services/Forum/ForumArchiver.php
@@ -4,6 +4,7 @@
 
 namespace Podium\Api\Services\Forum;
 
+use InvalidArgumentException;
 use Podium\Api\Components\PodiumResponse;
 use Podium\Api\Events\ArchiveEvent;
 use Podium\Api\Interfaces\ArchiverInterface;
@@ -38,7 +39,17 @@ private function beforeArchive(): bool
      */
     public function archive(RepositoryInterface $forum): PodiumResponse
     {
-        if (!$forum instanceof ForumRepositoryInterface || !$this->beforeArchive()) {
+        if (!$forum instanceof ForumRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Forum must be instance of Podium\Api\Interfaces\ForumRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$this->beforeArchive()) {
             return PodiumResponse::error();
         }
 
@@ -94,7 +105,17 @@ private function beforeRevive(): bool
      */
     public function revive(RepositoryInterface $forum): PodiumResponse
     {
-        if (!$forum instanceof ForumRepositoryInterface || !$this->beforeRevive()) {
+        if (!$forum instanceof ForumRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Forum must be instance of Podium\Api\Interfaces\ForumRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$this->beforeRevive()) {
             return PodiumResponse::error();
         }
 
diff --git a/src/Services/Forum/ForumBuilder.php b/src/Services/Forum/ForumBuilder.php
index 1471168..383bafe 100644
--- a/src/Services/Forum/ForumBuilder.php
+++ b/src/Services/Forum/ForumBuilder.php
@@ -4,6 +4,7 @@
 
 namespace Podium\Api\Services\Forum;
 
+use InvalidArgumentException;
 use Podium\Api\Components\PodiumResponse;
 use Podium\Api\Events\BuildEvent;
 use Podium\Api\Interfaces\CategorisedBuilderInterface;
@@ -44,11 +45,27 @@ public function create(
         RepositoryInterface $category,
         array $data = []
     ): PodiumResponse {
-        if (
-            !$forum instanceof ForumRepositoryInterface
-            || !$category instanceof CategoryRepositoryInterface
-            || !$this->beforeCreate()
-        ) {
+        if (!$forum instanceof ForumRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Forum must be instance of Podium\Api\Interfaces\ForumRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$category instanceof CategoryRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Category must be instance of Podium\Api\Interfaces\CategoryRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$this->beforeCreate()) {
             return PodiumResponse::error();
         }
 
@@ -100,7 +117,17 @@ private function beforeEdit(): bool
      */
     public function edit(RepositoryInterface $forum, array $data = []): PodiumResponse
     {
-        if (!$forum instanceof ForumRepositoryInterface || !$this->beforeEdit()) {
+        if (!$forum instanceof ForumRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Forum must be instance of Podium\Api\Interfaces\ForumRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$this->beforeEdit()) {
             return PodiumResponse::error();
         }
 
diff --git a/src/Services/Forum/ForumMover.php b/src/Services/Forum/ForumMover.php
index 04d0143..a048a68 100644
--- a/src/Services/Forum/ForumMover.php
+++ b/src/Services/Forum/ForumMover.php
@@ -4,6 +4,7 @@
 
 namespace Podium\Api\Services\Forum;
 
+use InvalidArgumentException;
 use Podium\Api\Components\PodiumResponse;
 use Podium\Api\Events\MoveEvent;
 use Podium\Api\Interfaces\CategoryRepositoryInterface;
@@ -37,11 +38,27 @@ private function beforeMove(): bool
      */
     public function move(RepositoryInterface $forum, RepositoryInterface $category): PodiumResponse
     {
-        if (
-            !$forum instanceof ForumRepositoryInterface
-            || !$category instanceof CategoryRepositoryInterface
-            || !$this->beforeMove()
-        ) {
+        if (!$forum instanceof ForumRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Forum must be instance of Podium\Api\Interfaces\ForumRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$category instanceof CategoryRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Category must be instance of Podium\Api\Interfaces\CategoryRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$this->beforeMove()) {
             return PodiumResponse::error();
         }
 
diff --git a/src/Services/Forum/ForumRemover.php b/src/Services/Forum/ForumRemover.php
index 4d7fcdf..651d37c 100644
--- a/src/Services/Forum/ForumRemover.php
+++ b/src/Services/Forum/ForumRemover.php
@@ -4,6 +4,7 @@
 
 namespace Podium\Api\Services\Forum;
 
+use InvalidArgumentException;
 use Podium\Api\Components\PodiumResponse;
 use Podium\Api\Events\RemoveEvent;
 use Podium\Api\Interfaces\ForumRepositoryInterface;
@@ -36,7 +37,17 @@ private function beforeRemove(): bool
      */
     public function remove(RepositoryInterface $forum): PodiumResponse
     {
-        if (!$forum instanceof ForumRepositoryInterface || !$this->beforeRemove()) {
+        if (!$forum instanceof ForumRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Forum must be instance of Podium\Api\Interfaces\ForumRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$this->beforeRemove()) {
             return PodiumResponse::error();
         }
 
diff --git a/src/Services/Forum/ForumSorter.php b/src/Services/Forum/ForumSorter.php
index 3e344df..fd80a85 100644
--- a/src/Services/Forum/ForumSorter.php
+++ b/src/Services/Forum/ForumSorter.php
@@ -4,6 +4,7 @@
 
 namespace Podium\Api\Services\Forum;
 
+use InvalidArgumentException;
 use Podium\Api\Components\PodiumResponse;
 use Podium\Api\Events\SortEvent;
 use Podium\Api\Interfaces\ForumRepositoryInterface;
@@ -39,11 +40,27 @@ private function beforeReplace(): bool
      */
     public function replace(RepositoryInterface $firstForum, RepositoryInterface $secondForum): PodiumResponse
     {
-        if (
-            !$firstForum instanceof ForumRepositoryInterface
-            || !$secondForum instanceof ForumRepositoryInterface
-            || !$this->beforeReplace()
-        ) {
+        if (!$firstForum instanceof ForumRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'First forum must be instance of Podium\Api\Interfaces\ForumRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$secondForum instanceof ForumRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Second forum must be instance of Podium\Api\Interfaces\ForumRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$this->beforeReplace()) {
             return PodiumResponse::error();
         }
 
@@ -98,7 +115,17 @@ private function beforeSort(): bool
      */
     public function sort(RepositoryInterface $forum): PodiumResponse
     {
-        if (!$forum instanceof ForumRepositoryInterface || !$this->beforeSort()) {
+        if (!$forum instanceof ForumRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Forum must be instance of Podium\Api\Interfaces\ForumRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$this->beforeSort()) {
             return PodiumResponse::error();
         }
 
diff --git a/src/Services/Group/GroupBuilder.php b/src/Services/Group/GroupBuilder.php
index 413736e..e60a6d7 100644
--- a/src/Services/Group/GroupBuilder.php
+++ b/src/Services/Group/GroupBuilder.php
@@ -4,6 +4,7 @@
 
 namespace Podium\Api\Services\Group;
 
+use InvalidArgumentException;
 use Podium\Api\Components\PodiumResponse;
 use Podium\Api\Events\BuildEvent;
 use Podium\Api\Interfaces\BuilderInterface;
@@ -38,7 +39,17 @@ private function beforeCreate(): bool
      */
     public function create(RepositoryInterface $group, array $data = []): PodiumResponse
     {
-        if (!$group instanceof GroupRepositoryInterface || !$this->beforeCreate()) {
+        if (!$group instanceof GroupRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Group must be instance of Podium\Api\Interfaces\GroupRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$this->beforeCreate()) {
             return PodiumResponse::error();
         }
 
@@ -90,7 +101,17 @@ private function beforeEdit(): bool
      */
     public function edit(RepositoryInterface $group, array $data = []): PodiumResponse
     {
-        if (!$group instanceof GroupRepositoryInterface || !$this->beforeEdit()) {
+        if (!$group instanceof GroupRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Group must be instance of Podium\Api\Interfaces\GroupRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$this->beforeEdit()) {
             return PodiumResponse::error();
         }
 
diff --git a/src/Services/Group/GroupRemover.php b/src/Services/Group/GroupRemover.php
index b0e39ea..bdbf645 100644
--- a/src/Services/Group/GroupRemover.php
+++ b/src/Services/Group/GroupRemover.php
@@ -4,6 +4,7 @@
 
 namespace Podium\Api\Services\Group;
 
+use InvalidArgumentException;
 use Podium\Api\Components\PodiumResponse;
 use Podium\Api\Events\RemoveEvent;
 use Podium\Api\Interfaces\GroupRepositoryInterface;
@@ -36,7 +37,17 @@ private function beforeRemove(): bool
      */
     public function remove(RepositoryInterface $group): PodiumResponse
     {
-        if (!$group instanceof GroupRepositoryInterface || !$this->beforeRemove()) {
+        if (!$group instanceof GroupRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Group must be instance of Podium\Api\Interfaces\GroupRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$this->beforeRemove()) {
             return PodiumResponse::error();
         }
 
diff --git a/src/Services/Logger/LoggerRemover.php b/src/Services/Logger/LoggerRemover.php
index f228e90..2d0ce6d 100644
--- a/src/Services/Logger/LoggerRemover.php
+++ b/src/Services/Logger/LoggerRemover.php
@@ -4,6 +4,7 @@
 
 namespace Podium\Api\Services\Logger;
 
+use InvalidArgumentException;
 use Podium\Api\Components\PodiumResponse;
 use Podium\Api\Events\RemoveEvent;
 use Podium\Api\Interfaces\LogRepositoryInterface;
@@ -36,7 +37,17 @@ private function beforeRemove(): bool
      */
     public function remove(RepositoryInterface $log): PodiumResponse
     {
-        if (!$log instanceof LogRepositoryInterface || !$this->beforeRemove()) {
+        if (!$log instanceof LogRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Log must be instance of Podium\Api\Interfaces\LogRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$this->beforeRemove()) {
             return PodiumResponse::error();
         }
 
diff --git a/src/Services/Member/MemberRemover.php b/src/Services/Member/MemberRemover.php
index 33f1a6e..cd62571 100644
--- a/src/Services/Member/MemberRemover.php
+++ b/src/Services/Member/MemberRemover.php
@@ -4,6 +4,7 @@
 
 namespace Podium\Api\Services\Member;
 
+use InvalidArgumentException;
 use Podium\Api\Components\PodiumResponse;
 use Podium\Api\Events\RemoveEvent;
 use Podium\Api\Interfaces\MemberRepositoryInterface;
@@ -36,7 +37,17 @@ private function beforeRemove(): bool
      */
     public function remove(RepositoryInterface $member): PodiumResponse
     {
-        if (!$member instanceof MemberRepositoryInterface || !$this->beforeRemove()) {
+        if (!$member instanceof MemberRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Member must be instance of Podium\Api\Interfaces\MemberRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$this->beforeRemove()) {
             return PodiumResponse::error();
         }
 
diff --git a/src/Services/Poll/PollRemover.php b/src/Services/Poll/PollRemover.php
index 3008d53..62fafcb 100644
--- a/src/Services/Poll/PollRemover.php
+++ b/src/Services/Poll/PollRemover.php
@@ -4,6 +4,7 @@
 
 namespace Podium\Api\Services\Poll;
 
+use InvalidArgumentException;
 use Podium\Api\Components\PodiumResponse;
 use Podium\Api\Events\RemoveEvent;
 use Podium\Api\Interfaces\PollPostRepositoryInterface;
@@ -33,7 +34,17 @@ private function beforeRemove(): bool
      */
     public function remove(RepositoryInterface $post): PodiumResponse
     {
-        if (!$post instanceof PollPostRepositoryInterface || !$this->beforeRemove()) {
+        if (!$post instanceof PollPostRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Post must be instance of Podium\Api\Interfaces\PollPostRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$this->beforeRemove()) {
             return PodiumResponse::error();
         }
 
diff --git a/src/Services/Post/PostArchiver.php b/src/Services/Post/PostArchiver.php
index a444403..a188e48 100644
--- a/src/Services/Post/PostArchiver.php
+++ b/src/Services/Post/PostArchiver.php
@@ -4,6 +4,7 @@
 
 namespace Podium\Api\Services\Post;
 
+use InvalidArgumentException;
 use Podium\Api\Components\PodiumResponse;
 use Podium\Api\Events\ArchiveEvent;
 use Podium\Api\Interfaces\ArchiverInterface;
@@ -38,7 +39,17 @@ private function beforeArchive(): bool
      */
     public function archive(RepositoryInterface $post): PodiumResponse
     {
-        if (!$post instanceof PostRepositoryInterface || !$this->beforeArchive()) {
+        if (!$post instanceof PostRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Post must be instance of Podium\Api\Interfaces\PostRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$this->beforeArchive()) {
             return PodiumResponse::error();
         }
 
@@ -94,7 +105,17 @@ private function beforeRevive(): bool
      */
     public function revive(RepositoryInterface $post): PodiumResponse
     {
-        if (!$post instanceof PostRepositoryInterface || !$this->beforeRevive()) {
+        if (!$post instanceof PostRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Post must be instance of Podium\Api\Interfaces\PostRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$this->beforeRevive()) {
             return PodiumResponse::error();
         }
 
diff --git a/src/Services/Post/PostBuilder.php b/src/Services/Post/PostBuilder.php
index eb5d893..a5d6915 100644
--- a/src/Services/Post/PostBuilder.php
+++ b/src/Services/Post/PostBuilder.php
@@ -4,6 +4,7 @@
 
 namespace Podium\Api\Services\Post;
 
+use InvalidArgumentException;
 use Podium\Api\Components\PodiumResponse;
 use Podium\Api\Events\BuildEvent;
 use Podium\Api\Interfaces\CategorisedBuilderInterface;
@@ -46,11 +47,27 @@ public function create(
         RepositoryInterface $thread,
         array $data = []
     ): PodiumResponse {
-        if (
-            !$post instanceof PostRepositoryInterface
-            || !$thread instanceof ThreadRepositoryInterface
-            || !$this->beforeCreate()
-        ) {
+        if (!$post instanceof PostRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Post must be instance of Podium\Api\Interfaces\PostRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$thread instanceof ThreadRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Thread must be instance of Podium\Api\Interfaces\ThreadRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$this->beforeCreate()) {
             return PodiumResponse::error();
         }
 
@@ -111,7 +128,17 @@ private function beforeEdit(): bool
      */
     public function edit(RepositoryInterface $post, array $data = []): PodiumResponse
     {
-        if (!$post instanceof PostRepositoryInterface || !$this->beforeEdit()) {
+        if (!$post instanceof PostRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Post must be instance of Podium\Api\Interfaces\PostRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$this->beforeEdit()) {
             return PodiumResponse::error();
         }
 
diff --git a/src/Services/Post/PostMover.php b/src/Services/Post/PostMover.php
index 3f2884f..ff5d272 100644
--- a/src/Services/Post/PostMover.php
+++ b/src/Services/Post/PostMover.php
@@ -4,6 +4,7 @@
 
 namespace Podium\Api\Services\Post;
 
+use InvalidArgumentException;
 use Podium\Api\Components\PodiumResponse;
 use Podium\Api\Events\MoveEvent;
 use Podium\Api\Interfaces\ForumRepositoryInterface;
@@ -39,11 +40,27 @@ private function beforeMove(): bool
      */
     public function move(RepositoryInterface $post, RepositoryInterface $thread): PodiumResponse
     {
-        if (
-            !$post instanceof PostRepositoryInterface
-            || !$thread instanceof ThreadRepositoryInterface
-            || !$this->beforeMove()
-        ) {
+        if (!$post instanceof PostRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Post must be instance of Podium\Api\Interfaces\PostRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$thread instanceof ThreadRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Thread must be instance of Podium\Api\Interfaces\ThreadRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$this->beforeMove()) {
             return PodiumResponse::error();
         }
 
diff --git a/src/Services/Post/PostPinner.php b/src/Services/Post/PostPinner.php
index ac60619..1a5ae0b 100644
--- a/src/Services/Post/PostPinner.php
+++ b/src/Services/Post/PostPinner.php
@@ -4,6 +4,7 @@
 
 namespace Podium\Api\Services\Post;
 
+use InvalidArgumentException;
 use Podium\Api\Components\PodiumResponse;
 use Podium\Api\Events\PinEvent;
 use Podium\Api\Interfaces\PinnerInterface;
@@ -38,7 +39,17 @@ private function beforePin(): bool
      */
     public function pin(RepositoryInterface $post): PodiumResponse
     {
-        if (!$post instanceof PostRepositoryInterface || !$this->beforePin()) {
+        if (!$post instanceof PostRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Post must be instance of Podium\Api\Interfaces\PostRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$this->beforePin()) {
             return PodiumResponse::error();
         }
 
@@ -90,7 +101,17 @@ private function beforeUnpin(): bool
      */
     public function unpin(RepositoryInterface $post): PodiumResponse
     {
-        if (!$post instanceof PostRepositoryInterface || !$this->beforeUnpin()) {
+        if (!$post instanceof PostRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Post must be instance of Podium\Api\Interfaces\PostRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$this->beforeUnpin()) {
             return PodiumResponse::error();
         }
 
diff --git a/src/Services/Post/PostRemover.php b/src/Services/Post/PostRemover.php
index adcf9e5..ae01bd7 100644
--- a/src/Services/Post/PostRemover.php
+++ b/src/Services/Post/PostRemover.php
@@ -4,6 +4,7 @@
 
 namespace Podium\Api\Services\Post;
 
+use InvalidArgumentException;
 use Podium\Api\Components\PodiumResponse;
 use Podium\Api\Events\RemoveEvent;
 use Podium\Api\Interfaces\ForumRepositoryInterface;
@@ -36,7 +37,17 @@ private function beforeRemove(): bool
      */
     public function remove(RepositoryInterface $post): PodiumResponse
     {
-        if (!$post instanceof PostRepositoryInterface || !$this->beforeRemove()) {
+        if (!$post instanceof PostRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Post must be instance of Podium\Api\Interfaces\PostRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$this->beforeRemove()) {
             return PodiumResponse::error();
         }
 
diff --git a/src/Services/Rank/RankBuilder.php b/src/Services/Rank/RankBuilder.php
index bb1db2a..d1286f7 100644
--- a/src/Services/Rank/RankBuilder.php
+++ b/src/Services/Rank/RankBuilder.php
@@ -4,6 +4,7 @@
 
 namespace Podium\Api\Services\Rank;
 
+use InvalidArgumentException;
 use Podium\Api\Components\PodiumResponse;
 use Podium\Api\Events\BuildEvent;
 use Podium\Api\Interfaces\BuilderInterface;
@@ -38,7 +39,17 @@ private function beforeCreate(): bool
      */
     public function create(RepositoryInterface $rank, array $data = []): PodiumResponse
     {
-        if (!$rank instanceof RankRepositoryInterface || !$this->beforeCreate()) {
+        if (!$rank instanceof RankRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Rank must be instance of Podium\Api\Interfaces\RankRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$this->beforeCreate()) {
             return PodiumResponse::error();
         }
 
@@ -90,7 +101,17 @@ private function beforeEdit(): bool
      */
     public function edit(RepositoryInterface $rank, array $data = []): PodiumResponse
     {
-        if (!$rank instanceof RankRepositoryInterface || !$this->beforeEdit()) {
+        if (!$rank instanceof RankRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Rank must be instance of Podium\Api\Interfaces\RankRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$this->beforeEdit()) {
             return PodiumResponse::error();
         }
 
diff --git a/src/Services/Rank/RankRemover.php b/src/Services/Rank/RankRemover.php
index 6b24390..8fb1d5b 100644
--- a/src/Services/Rank/RankRemover.php
+++ b/src/Services/Rank/RankRemover.php
@@ -4,6 +4,7 @@
 
 namespace Podium\Api\Services\Rank;
 
+use InvalidArgumentException;
 use Podium\Api\Components\PodiumResponse;
 use Podium\Api\Events\RemoveEvent;
 use Podium\Api\Interfaces\RankRepositoryInterface;
@@ -36,7 +37,17 @@ private function beforeRemove(): bool
      */
     public function remove(RepositoryInterface $rank): PodiumResponse
     {
-        if (!$rank instanceof RankRepositoryInterface || !$this->beforeRemove()) {
+        if (!$rank instanceof RankRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Rank must be instance of Podium\Api\Interfaces\RankRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$this->beforeRemove()) {
             return PodiumResponse::error();
         }
 
diff --git a/src/Services/Thread/ThreadArchiver.php b/src/Services/Thread/ThreadArchiver.php
index e467f1b..61e7745 100644
--- a/src/Services/Thread/ThreadArchiver.php
+++ b/src/Services/Thread/ThreadArchiver.php
@@ -4,6 +4,7 @@
 
 namespace Podium\Api\Services\Thread;
 
+use InvalidArgumentException;
 use Podium\Api\Components\PodiumResponse;
 use Podium\Api\Events\ArchiveEvent;
 use Podium\Api\Interfaces\ArchiverInterface;
@@ -38,7 +39,17 @@ private function beforeArchive(): bool
      */
     public function archive(RepositoryInterface $thread): PodiumResponse
     {
-        if (!$thread instanceof ThreadRepositoryInterface || !$this->beforeArchive()) {
+        if (!$thread instanceof ThreadRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Thread must be instance of Podium\Api\Interfaces\ThreadRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$this->beforeArchive()) {
             return PodiumResponse::error();
         }
 
@@ -94,7 +105,17 @@ private function beforeRevive(): bool
      */
     public function revive(RepositoryInterface $thread): PodiumResponse
     {
-        if (!$thread instanceof ThreadRepositoryInterface || !$this->beforeRevive()) {
+        if (!$thread instanceof ThreadRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Thread must be instance of Podium\Api\Interfaces\ThreadRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$this->beforeRevive()) {
             return PodiumResponse::error();
         }
 
diff --git a/src/Services/Thread/ThreadBuilder.php b/src/Services/Thread/ThreadBuilder.php
index ca4d083..a4d97c6 100644
--- a/src/Services/Thread/ThreadBuilder.php
+++ b/src/Services/Thread/ThreadBuilder.php
@@ -4,6 +4,7 @@
 
 namespace Podium\Api\Services\Thread;
 
+use InvalidArgumentException;
 use Podium\Api\Components\PodiumResponse;
 use Podium\Api\Events\BuildEvent;
 use Podium\Api\Interfaces\CategorisedBuilderInterface;
@@ -45,11 +46,27 @@ public function create(
         RepositoryInterface $forum,
         array $data = []
     ): PodiumResponse {
-        if (
-            !$thread instanceof ThreadRepositoryInterface
-            || !$forum instanceof ForumRepositoryInterface
-            || !$this->beforeCreate()
-        ) {
+        if (!$thread instanceof ThreadRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Thread must be instance of Podium\Api\Interfaces\ThreadRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$forum instanceof ForumRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Forum must be instance of Podium\Api\Interfaces\ForumRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$this->beforeCreate()) {
             return PodiumResponse::error();
         }
 
@@ -105,7 +122,17 @@ private function beforeEdit(): bool
      */
     public function edit(RepositoryInterface $thread, array $data = []): PodiumResponse
     {
-        if (!$thread instanceof ThreadRepositoryInterface || !$this->beforeEdit()) {
+        if (!$thread instanceof ThreadRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Thread must be instance of Podium\Api\Interfaces\ThreadRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$this->beforeEdit()) {
             return PodiumResponse::error();
         }
 
diff --git a/src/Services/Thread/ThreadMover.php b/src/Services/Thread/ThreadMover.php
index 70944f9..62a6532 100644
--- a/src/Services/Thread/ThreadMover.php
+++ b/src/Services/Thread/ThreadMover.php
@@ -4,6 +4,7 @@
 
 namespace Podium\Api\Services\Thread;
 
+use InvalidArgumentException;
 use Podium\Api\Components\PodiumResponse;
 use Podium\Api\Events\MoveEvent;
 use Podium\Api\Interfaces\ForumRepositoryInterface;
@@ -38,11 +39,27 @@ private function beforeMove(): bool
      */
     public function move(RepositoryInterface $thread, RepositoryInterface $forum): PodiumResponse
     {
-        if (
-            !$thread instanceof ThreadRepositoryInterface
-            || !$forum instanceof ForumRepositoryInterface
-            || !$this->beforeMove()
-        ) {
+        if (!$thread instanceof ThreadRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Thread must be instance of Podium\Api\Interfaces\ThreadRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$forum instanceof ForumRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Forum must be instance of Podium\Api\Interfaces\ForumRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$this->beforeMove()) {
             return PodiumResponse::error();
         }
 
diff --git a/src/Services/Thread/ThreadPinner.php b/src/Services/Thread/ThreadPinner.php
index cb04d19..8935d0e 100644
--- a/src/Services/Thread/ThreadPinner.php
+++ b/src/Services/Thread/ThreadPinner.php
@@ -4,6 +4,7 @@
 
 namespace Podium\Api\Services\Thread;
 
+use InvalidArgumentException;
 use Podium\Api\Components\PodiumResponse;
 use Podium\Api\Events\PinEvent;
 use Podium\Api\Interfaces\PinnerInterface;
@@ -38,7 +39,17 @@ private function beforePin(): bool
      */
     public function pin(RepositoryInterface $thread): PodiumResponse
     {
-        if (!$thread instanceof ThreadRepositoryInterface || !$this->beforePin()) {
+        if (!$thread instanceof ThreadRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Thread must be instance of Podium\Api\Interfaces\ThreadRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$this->beforePin()) {
             return PodiumResponse::error();
         }
 
@@ -90,7 +101,17 @@ private function beforeUnpin(): bool
      */
     public function unpin(RepositoryInterface $thread): PodiumResponse
     {
-        if (!$thread instanceof ThreadRepositoryInterface || !$this->beforeUnpin()) {
+        if (!$thread instanceof ThreadRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Thread must be instance of Podium\Api\Interfaces\ThreadRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$this->beforeUnpin()) {
             return PodiumResponse::error();
         }
 
diff --git a/src/Services/Thread/ThreadRemover.php b/src/Services/Thread/ThreadRemover.php
index 77a4fe4..6beec36 100644
--- a/src/Services/Thread/ThreadRemover.php
+++ b/src/Services/Thread/ThreadRemover.php
@@ -4,6 +4,7 @@
 
 namespace Podium\Api\Services\Thread;
 
+use InvalidArgumentException;
 use Podium\Api\Components\PodiumResponse;
 use Podium\Api\Events\RemoveEvent;
 use Podium\Api\Interfaces\ForumRepositoryInterface;
@@ -38,7 +39,17 @@ private function beforeRemove(): bool
      */
     public function remove(RepositoryInterface $thread): PodiumResponse
     {
-        if (!$thread instanceof ThreadRepositoryInterface || !$this->beforeRemove()) {
+        if (!$thread instanceof ThreadRepositoryInterface) {
+            return PodiumResponse::error(
+                [
+                    'exception' => new InvalidArgumentException(
+                        'Thread must be instance of Podium\Api\Interfaces\ThreadRepositoryInterface!'
+                    ),
+                ]
+            );
+        }
+
+        if (!$this->beforeRemove()) {
             return PodiumResponse::error();
         }
 
diff --git a/tests/Functional/Forum/ForumMoverTest.php b/tests/Functional/Forum/ForumMoverTest.php
index 61a0a0e..c312571 100644
--- a/tests/Functional/Forum/ForumMoverTest.php
+++ b/tests/Functional/Forum/ForumMoverTest.php
@@ -30,12 +30,14 @@ public function testMoveShouldTriggerBeforeAndAfterEventsWhenMovingIsDone(): voi
             $this->eventsRaised[ForumMover::EVENT_BEFORE_MOVING] = $event instanceof MoveEvent;
         };
         Event::on(ForumMover::class, ForumMover::EVENT_BEFORE_MOVING, $beforeHandler);
-        $afterHandler = function () {
-            $this->eventsRaised[ForumMover::EVENT_AFTER_MOVING] = true;
+        $afterHandler = function ($event) {
+            $this->eventsRaised[ForumMover::EVENT_AFTER_MOVING] = $event instanceof MoveEvent
+                && 11 === $event->repository->getId();
         };
         Event::on(ForumMover::class, ForumMover::EVENT_AFTER_MOVING, $afterHandler);
 
         $forum = $this->createMock(ForumRepositoryInterface::class);
+        $forum->method('getId')->willReturn(11);
         $forum->method('move')->willReturn(true);
         $this->service->move($forum, $this->createMock(CategoryRepositoryInterface::class));
 
diff --git a/tests/Functional/Group/GroupKeeperTest.php b/tests/Functional/Group/GroupKeeperTest.php
index 7de4d35..9f21a3a 100644
--- a/tests/Functional/Group/GroupKeeperTest.php
+++ b/tests/Functional/Group/GroupKeeperTest.php
@@ -32,7 +32,8 @@ public function testJoinShouldTriggerBeforeAndAfterEventsWhenCreatingGroupMember
         };
         Event::on(GroupKeeper::class, GroupKeeper::EVENT_BEFORE_JOINING, $beforeHandler);
         $afterHandler = function ($event) {
-            $this->eventsRaised[GroupKeeper::EVENT_AFTER_JOINING] = $event instanceof GroupEvent;
+            $this->eventsRaised[GroupKeeper::EVENT_AFTER_JOINING] = $event instanceof GroupEvent
+                && $event->repository instanceof GroupMemberRepositoryInterface;
         };
         Event::on(GroupKeeper::class, GroupKeeper::EVENT_AFTER_JOINING, $afterHandler);
 
diff --git a/tests/Functional/Member/MemberAcquaintanceTest.php b/tests/Functional/Member/MemberAcquaintanceTest.php
index 55ff66f..c0663e4 100644
--- a/tests/Functional/Member/MemberAcquaintanceTest.php
+++ b/tests/Functional/Member/MemberAcquaintanceTest.php
@@ -31,7 +31,8 @@ public function testBefriendShouldTriggerBeforeAndAfterEventsWhenBefriendingIsDo
         };
         Event::on(MemberAcquaintance::class, MemberAcquaintance::EVENT_BEFORE_BEFRIENDING, $beforeHandler);
         $afterHandler = function ($event) {
-            $this->eventsRaised[MemberAcquaintance::EVENT_AFTER_BEFRIENDING] = $event instanceof AcquaintanceEvent;
+            $this->eventsRaised[MemberAcquaintance::EVENT_AFTER_BEFRIENDING] = $event instanceof AcquaintanceEvent
+                && $event->repository instanceof AcquaintanceRepositoryInterface;
         };
         Event::on(MemberAcquaintance::class, MemberAcquaintance::EVENT_AFTER_BEFRIENDING, $afterHandler);
 
@@ -234,7 +235,8 @@ public function testIgnoreShouldTriggerBeforeAndAfterEventsWhenIgnoringIsDone():
         };
         Event::on(MemberAcquaintance::class, MemberAcquaintance::EVENT_BEFORE_IGNORING, $beforeHandler);
         $afterHandler = function ($event) {
-            $this->eventsRaised[MemberAcquaintance::EVENT_AFTER_IGNORING] = $event instanceof AcquaintanceEvent;
+            $this->eventsRaised[MemberAcquaintance::EVENT_AFTER_IGNORING] = $event instanceof AcquaintanceEvent
+                && $event->repository instanceof AcquaintanceRepositoryInterface;
         };
         Event::on(MemberAcquaintance::class, MemberAcquaintance::EVENT_AFTER_IGNORING, $afterHandler);
 
diff --git a/tests/Functional/Post/PostLikerTest.php b/tests/Functional/Post/PostLikerTest.php
index e839e3b..217261d 100644
--- a/tests/Functional/Post/PostLikerTest.php
+++ b/tests/Functional/Post/PostLikerTest.php
@@ -32,7 +32,8 @@ public function testThumbUpShouldTriggerBeforeAndAfterEventsWhenUpIsDone(): void
         };
         Event::on(PostLiker::class, PostLiker::EVENT_BEFORE_THUMB_UP, $beforeHandler);
         $afterHandler = function ($event) {
-            $this->eventsRaised[PostLiker::EVENT_AFTER_THUMB_UP] = $event instanceof ThumbEvent;
+            $this->eventsRaised[PostLiker::EVENT_AFTER_THUMB_UP] = $event instanceof ThumbEvent
+                && $event->repository instanceof ThumbRepositoryInterface;
         };
         Event::on(PostLiker::class, PostLiker::EVENT_AFTER_THUMB_UP, $afterHandler);
 
@@ -131,7 +132,8 @@ public function testThumbDownShouldTriggerBeforeAndAfterEventsWhenDownIsDone():
         };
         Event::on(PostLiker::class, PostLiker::EVENT_BEFORE_THUMB_DOWN, $beforeHandler);
         $afterHandler = function ($event) {
-            $this->eventsRaised[PostLiker::EVENT_AFTER_THUMB_DOWN] = $event instanceof ThumbEvent;
+            $this->eventsRaised[PostLiker::EVENT_AFTER_THUMB_DOWN] = $event instanceof ThumbEvent
+                && $event->repository instanceof ThumbRepositoryInterface;
         };
         Event::on(PostLiker::class, PostLiker::EVENT_AFTER_THUMB_DOWN, $afterHandler);
 
diff --git a/tests/Functional/Post/PostMoverTest.php b/tests/Functional/Post/PostMoverTest.php
index 73ef75c..865b2b2 100644
--- a/tests/Functional/Post/PostMoverTest.php
+++ b/tests/Functional/Post/PostMoverTest.php
@@ -31,13 +31,15 @@ public function testMoveShouldTriggerBeforeAndAfterEventsWhenMovingIsDone(): voi
             $this->eventsRaised[PostMover::EVENT_BEFORE_MOVING] = $event instanceof MoveEvent;
         };
         Event::on(PostMover::class, PostMover::EVENT_BEFORE_MOVING, $beforeHandler);
-        $afterHandler = function () {
-            $this->eventsRaised[PostMover::EVENT_AFTER_MOVING] = true;
+        $afterHandler = function ($event) {
+            $this->eventsRaised[PostMover::EVENT_AFTER_MOVING] = $event instanceof MoveEvent
+                && 77 === $event->repository->getId();
         };
         Event::on(PostMover::class, PostMover::EVENT_AFTER_MOVING, $afterHandler);
 
         $post = $this->createMock(PostRepositoryInterface::class);
         $post->method('move')->willReturn(true);
+        $post->method('getId')->willReturn(77);
         $thread = $this->createMock(ThreadRepositoryInterface::class);
         $thread->method('updateCounters')->willReturn(true);
         $forum = $this->createMock(ForumRepositoryInterface::class);
diff --git a/tests/Functional/Thread/ThreadBookmarkerTest.php b/tests/Functional/Thread/ThreadBookmarkerTest.php
index b11c0ae..0570937 100644
--- a/tests/Functional/Thread/ThreadBookmarkerTest.php
+++ b/tests/Functional/Thread/ThreadBookmarkerTest.php
@@ -33,7 +33,8 @@ public function testMarkShouldTriggerBeforeAndAfterEventsWhenMarkingIsDone(): vo
         };
         Event::on(ThreadBookmarker::class, ThreadBookmarker::EVENT_BEFORE_MARKING, $beforeHandler);
         $afterHandler = function ($event) {
-            $this->eventsRaised[ThreadBookmarker::EVENT_AFTER_MARKING] = $event instanceof BookmarkEvent;
+            $this->eventsRaised[ThreadBookmarker::EVENT_AFTER_MARKING] = $event instanceof BookmarkEvent
+                && $event->repository instanceof BookmarkRepositoryInterface;
         };
         Event::on(ThreadBookmarker::class, ThreadBookmarker::EVENT_AFTER_MARKING, $afterHandler);
 
diff --git a/tests/Functional/Thread/ThreadMoverTest.php b/tests/Functional/Thread/ThreadMoverTest.php
index d86e8cf..d5f9d9a 100644
--- a/tests/Functional/Thread/ThreadMoverTest.php
+++ b/tests/Functional/Thread/ThreadMoverTest.php
@@ -30,13 +30,15 @@ public function testMoveShouldTriggerBeforeAndAfterEventsWhenMovingIsDone(): voi
             $this->eventsRaised[ThreadMover::EVENT_BEFORE_MOVING] = $event instanceof MoveEvent;
         };
         Event::on(ThreadMover::class, ThreadMover::EVENT_BEFORE_MOVING, $beforeHandler);
-        $afterHandler = function () {
-            $this->eventsRaised[ThreadMover::EVENT_AFTER_MOVING] = true;
+        $afterHandler = function ($event) {
+            $this->eventsRaised[ThreadMover::EVENT_AFTER_MOVING] = $event instanceof MoveEvent
+                && 54 === $event->repository->getId();
         };
         Event::on(ThreadMover::class, ThreadMover::EVENT_AFTER_MOVING, $afterHandler);
 
         $thread = $this->createMock(ThreadRepositoryInterface::class);
         $thread->method('move')->willReturn(true);
+        $thread->method('getId')->willReturn(54);
         $forum = $this->createMock(ForumRepositoryInterface::class);
         $forum->method('updateCounters')->willReturn(true);
         $thread->method('getParent')->willReturn($forum);
diff --git a/tests/Functional/Thread/ThreadSubscriberTest.php b/tests/Functional/Thread/ThreadSubscriberTest.php
index 90fd7b8..b74cbd4 100644
--- a/tests/Functional/Thread/ThreadSubscriberTest.php
+++ b/tests/Functional/Thread/ThreadSubscriberTest.php
@@ -32,7 +32,8 @@ public function testSubscribeShouldTriggerBeforeAndAfterEventsWhenSubscribingIsD
         };
         Event::on(ThreadSubscriber::class, ThreadSubscriber::EVENT_BEFORE_SUBSCRIBING, $beforeHandler);
         $afterHandler = function ($event) {
-            $this->eventsRaised[ThreadSubscriber::EVENT_AFTER_SUBSCRIBING] = $event instanceof SubscriptionEvent;
+            $this->eventsRaised[ThreadSubscriber::EVENT_AFTER_SUBSCRIBING] = $event instanceof SubscriptionEvent
+                && $event->repository instanceof SubscriptionRepositoryInterface;
         };
         Event::on(ThreadSubscriber::class, ThreadSubscriber::EVENT_AFTER_SUBSCRIBING, $afterHandler);
 
diff --git a/tests/Unit/Category/CategoryArchiverTest.php b/tests/Unit/Category/CategoryArchiverTest.php
index b6d415c..c24c7aa 100644
--- a/tests/Unit/Category/CategoryArchiverTest.php
+++ b/tests/Unit/Category/CategoryArchiverTest.php
@@ -27,7 +27,10 @@ public function testArchiveShouldReturnErrorWhenRepositoryIsWrong(): void
         $result = $this->service->archive($this->createMock(RepositoryInterface::class));
 
         self::assertFalse($result->getResult());
-        self::assertEmpty($result->getErrors());
+        self::assertSame(
+            'Category must be instance of Podium\Api\Interfaces\CategoryRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
     }
 
     public function testArchiveShouldReturnErrorWhenArchivingErrored(): void
@@ -97,7 +100,10 @@ public function testReviveShouldReturnErrorWhenRepositoryIsWrong(): void
         $result = $this->service->revive($this->createMock(RepositoryInterface::class));
 
         self::assertFalse($result->getResult());
-        self::assertEmpty($result->getErrors());
+        self::assertSame(
+            'Category must be instance of Podium\Api\Interfaces\CategoryRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
     }
 
     public function testReviveShouldReturnErrorWhenRevivingErrored(): void
diff --git a/tests/Unit/Category/CategoryRemoverTest.php b/tests/Unit/Category/CategoryRemoverTest.php
index 568f168..b3a03c1 100644
--- a/tests/Unit/Category/CategoryRemoverTest.php
+++ b/tests/Unit/Category/CategoryRemoverTest.php
@@ -25,7 +25,10 @@ public function testRemoveShouldReturnErrorWhenRepositoryIsWrong(): void
         $result = $this->service->remove($this->createMock(RepositoryInterface::class));
 
         self::assertFalse($result->getResult());
-        self::assertEmpty($result->getErrors());
+        self::assertSame(
+            'Category must be instance of Podium\Api\Interfaces\CategoryRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
     }
 
     public function testRemoveShouldReturnErrorWhenRemovingErrored(): void
diff --git a/tests/Unit/Category/CategorySorterTest.php b/tests/Unit/Category/CategorySorterTest.php
index c6aa0b4..b815ab7 100644
--- a/tests/Unit/Category/CategorySorterTest.php
+++ b/tests/Unit/Category/CategorySorterTest.php
@@ -28,7 +28,10 @@ public function testReplaceShouldReturnErrorWhenFirstRepositoryIsWrong(): void
         );
 
         self::assertFalse($result->getResult());
-        self::assertEmpty($result->getErrors());
+        self::assertSame(
+            'First category must be instance of Podium\Api\Interfaces\CategoryRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
     }
 
     public function testReplaceShouldReturnErrorWhenSecondRepositoryIsWrong(): void
@@ -39,49 +42,76 @@ public function testReplaceShouldReturnErrorWhenSecondRepositoryIsWrong(): void
         );
 
         self::assertFalse($result->getResult());
-        self::assertEmpty($result->getErrors());
+        self::assertSame(
+            'Second category must be instance of Podium\Api\Interfaces\CategoryRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
+    }
+
+    public function testReplaceShouldReturnSuccessWhenReplacingIsDone(): void
+    {
+        $this->transaction->expects(self::once())->method('commit');
+
+        $category = $this->createMock(CategoryRepositoryInterface::class);
+        $category->method('getOrder')->willReturn(1);
+        $category->method('setOrder')->willReturn(true);
+        $result = $this->service->replace($category, $category);
+
+        self::assertTrue($result->getResult());
     }
 
-    public function testReplaceShouldReturnErrorWhenSettingFirstOrderErrored(): void
+    public function testReplaceShouldReturnErrorWhenReplacingThrowsException(): void
     {
         $this->transaction->expects(self::once())->method('rollBack');
+        $this->logger->expects(self::once())->method('log')->with(
+            self::callback(
+                static function (array $data) {
+                    return 3 === count($data)
+                        && 'Exception while replacing categories order' === $data[0]
+                        && 'exc' === $data[1];
+                }
+            ),
+            1,
+            'podium'
+        );
 
         $category = $this->createMock(CategoryRepositoryInterface::class);
         $category->method('getOrder')->willReturn(1);
-        $category->method('setOrder')->willReturn(false);
+        $category->method('setOrder')->willThrowException(new Exception('exc'));
         $result = $this->service->replace($category, $category);
 
         self::assertFalse($result->getResult());
+        self::assertSame('exc', $result->getErrors()['exception']->getMessage());
     }
 
-    public function testReplaceShouldReturnErrorWhenSettingSecondOrderErrored(): void
+    public function testReplaceShouldReturnErrorWhenSettingFirstCategoryOrderErrored(): void
     {
         $this->transaction->expects(self::once())->method('rollBack');
+        $this->logger->expects(self::once())->method('log')->with(
+            self::callback(
+                static function (array $data) {
+                    return 3 === count($data)
+                        && 'Exception while replacing categories order' === $data[0]
+                        && 'Error while setting new category order!' === $data[1];
+                }
+            ),
+            1,
+            'podium'
+        );
 
         $category1 = $this->createMock(CategoryRepositoryInterface::class);
         $category1->method('getOrder')->willReturn(1);
-        $category1->method('setOrder')->willReturn(true);
+        $category1->method('setOrder')->willReturn(false);
         $category2 = $this->createMock(CategoryRepositoryInterface::class);
         $category2->method('getOrder')->willReturn(2);
-        $category2->method('setOrder')->willReturn(false);
+        $category2->method('setOrder')->willReturn(true);
         $result = $this->service->replace($category1, $category2);
 
         self::assertFalse($result->getResult());
+        self::assertSame('Error while setting new category order!', $result->getErrors()['exception']->getMessage());
     }
 
-    public function testReplaceShouldReturnSuccessWhenReplacingIsDone(): void
-    {
-        $this->transaction->expects(self::once())->method('commit');
-
-        $category = $this->createMock(CategoryRepositoryInterface::class);
-        $category->method('getOrder')->willReturn(1);
-        $category->method('setOrder')->willReturn(true);
-        $result = $this->service->replace($category, $category);
-
-        self::assertTrue($result->getResult());
-    }
-
-    public function testReplaceShouldReturnErrorWhenReplacingThrowsException(): void
+    public function testReplaceShouldReturnErrorWhenSettingSecondCategoryOrderErrored(): void
     {
         $this->transaction->expects(self::once())->method('rollBack');
         $this->logger->expects(self::once())->method('log')->with(
@@ -89,20 +119,34 @@ public function testReplaceShouldReturnErrorWhenReplacingThrowsException(): void
                 static function (array $data) {
                     return 3 === count($data)
                         && 'Exception while replacing categories order' === $data[0]
-                        && 'exc' === $data[1];
+                        && 'Error while setting new category order!' === $data[1];
                 }
             ),
             1,
             'podium'
         );
 
-        $category = $this->createMock(CategoryRepositoryInterface::class);
-        $category->method('getOrder')->willReturn(1);
-        $category->method('setOrder')->willThrowException(new Exception('exc'));
-        $result = $this->service->replace($category, $category);
+        $category1 = $this->createMock(CategoryRepositoryInterface::class);
+        $category1->method('getOrder')->willReturn(1);
+        $category1->method('setOrder')->willReturn(true);
+        $category2 = $this->createMock(CategoryRepositoryInterface::class);
+        $category2->method('getOrder')->willReturn(2);
+        $category2->method('setOrder')->willReturn(false);
+        $result = $this->service->replace($category1, $category2);
 
         self::assertFalse($result->getResult());
-        self::assertSame('exc', $result->getErrors()['exception']->getMessage());
+        self::assertSame('Error while setting new category order!', $result->getErrors()['exception']->getMessage());
+    }
+
+    public function testSortShouldReturnErrorWhenRepositoryIsWrong(): void
+    {
+        $result = $this->service->sort($this->createMock(RepositoryInterface::class));
+
+        self::assertFalse($result->getResult());
+        self::assertSame(
+            'Category must be instance of Podium\Api\Interfaces\CategoryRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
     }
 
     public function testSortShouldReturnErrorWhenSortingErrored(): void
diff --git a/tests/Unit/Forum/ForumArchiverTest.php b/tests/Unit/Forum/ForumArchiverTest.php
index 8d361fb..7d7f030 100644
--- a/tests/Unit/Forum/ForumArchiverTest.php
+++ b/tests/Unit/Forum/ForumArchiverTest.php
@@ -25,7 +25,10 @@ public function testArchiveShouldReturnErrorWhenRepositoryIsWrong(): void
         $result = $this->service->archive($this->createMock(RepositoryInterface::class));
 
         self::assertFalse($result->getResult());
-        self::assertEmpty($result->getErrors());
+        self::assertSame(
+            'Forum must be instance of Podium\Api\Interfaces\ForumRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
     }
 
     public function testArchiveShouldReturnErrorWhenArchivingErrored(): void
@@ -92,7 +95,10 @@ public function testReviveShouldReturnErrorWhenRepositoryIsWrong(): void
         $result = $this->service->revive($this->createMock(RepositoryInterface::class));
 
         self::assertFalse($result->getResult());
-        self::assertEmpty($result->getErrors());
+        self::assertSame(
+            'Forum must be instance of Podium\Api\Interfaces\ForumRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
     }
 
     public function testReviveShouldReturnErrorWhenRevivingErrored(): void
diff --git a/tests/Unit/Forum/ForumBuilderTest.php b/tests/Unit/Forum/ForumBuilderTest.php
index 11ef5ed..81572dd 100644
--- a/tests/Unit/Forum/ForumBuilderTest.php
+++ b/tests/Unit/Forum/ForumBuilderTest.php
@@ -22,15 +22,34 @@ protected function setUp(): void
         $this->service = new ForumBuilder();
     }
 
-    public function testCreateShouldReturnErrorWhenRepositoryIsWrong(): void
+    public function testCreateShouldReturnErrorWhenForumRepositoryIsWrong(): void
     {
         $result = $this->service->create(
             $this->createMock(RepositoryInterface::class),
             $this->createMock(MemberRepositoryInterface::class),
+            $this->createMock(CategoryRepositoryInterface::class)
+        );
+
+        self::assertFalse($result->getResult());
+        self::assertSame(
+            'Forum must be instance of Podium\Api\Interfaces\ForumRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
+    }
+
+    public function testCreateShouldReturnErrorWhenCategoryRepositoryIsWrong(): void
+    {
+        $result = $this->service->create(
+            $this->createMock(ForumRepositoryInterface::class),
+            $this->createMock(MemberRepositoryInterface::class),
             $this->createMock(RepositoryInterface::class)
         );
 
         self::assertFalse($result->getResult());
+        self::assertSame(
+            'Category must be instance of Podium\Api\Interfaces\CategoryRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
     }
 
     public function testCreateShouldReturnErrorWhenCreatingErrored(): void
@@ -95,6 +114,10 @@ public function testEditShouldReturnErrorWhenRepositoryIsWrong(): void
         $result = $this->service->edit($this->createMock(RepositoryInterface::class));
 
         self::assertFalse($result->getResult());
+        self::assertSame(
+            'Forum must be instance of Podium\Api\Interfaces\ForumRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
     }
 
     public function testEditShouldReturnErrorWhenEditingErrored(): void
diff --git a/tests/Unit/Forum/ForumMoverTest.php b/tests/Unit/Forum/ForumMoverTest.php
index d164b8d..e8b0135 100644
--- a/tests/Unit/Forum/ForumMoverTest.php
+++ b/tests/Unit/Forum/ForumMoverTest.php
@@ -29,7 +29,10 @@ public function testMoveShouldReturnErrorWhenForumRepositoryIsWrong(): void
         );
 
         self::assertFalse($result->getResult());
-        self::assertEmpty($result->getErrors());
+        self::assertSame(
+            'Forum must be instance of Podium\Api\Interfaces\ForumRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
     }
 
     public function testMoveShouldReturnErrorWhenCategoryRepositoryIsWrong(): void
@@ -40,7 +43,10 @@ public function testMoveShouldReturnErrorWhenCategoryRepositoryIsWrong(): void
         );
 
         self::assertFalse($result->getResult());
-        self::assertEmpty($result->getErrors());
+        self::assertSame(
+            'Category must be instance of Podium\Api\Interfaces\CategoryRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
     }
 
     public function testMoveShouldReturnErrorWhenMovingErrored(): void
diff --git a/tests/Unit/Forum/ForumRemoverTest.php b/tests/Unit/Forum/ForumRemoverTest.php
index c597881..8045458 100644
--- a/tests/Unit/Forum/ForumRemoverTest.php
+++ b/tests/Unit/Forum/ForumRemoverTest.php
@@ -25,7 +25,10 @@ public function testRemoveShouldReturnErrorWhenRepositoryIsWrong(): void
         $result = $this->service->remove($this->createMock(RepositoryInterface::class));
 
         self::assertFalse($result->getResult());
-        self::assertEmpty($result->getErrors());
+        self::assertSame(
+            'Forum must be instance of Podium\Api\Interfaces\ForumRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
     }
 
     public function testRemoveShouldReturnErrorWhenRemovingErrored(): void
diff --git a/tests/Unit/Forum/ForumSorterTest.php b/tests/Unit/Forum/ForumSorterTest.php
index 591e354..d68ace8 100644
--- a/tests/Unit/Forum/ForumSorterTest.php
+++ b/tests/Unit/Forum/ForumSorterTest.php
@@ -28,7 +28,10 @@ public function testReplaceShouldReturnErrorWhenFirstRepositoryIsWrong(): void
         );
 
         self::assertFalse($result->getResult());
-        self::assertEmpty($result->getErrors());
+        self::assertSame(
+            'First forum must be instance of Podium\Api\Interfaces\ForumRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
     }
 
     public function testReplaceShouldReturnErrorWhenSecondRepositoryIsWrong(): void
@@ -39,24 +42,53 @@ public function testReplaceShouldReturnErrorWhenSecondRepositoryIsWrong(): void
         );
 
         self::assertFalse($result->getResult());
-        self::assertEmpty($result->getErrors());
+        self::assertSame(
+            'Second forum must be instance of Podium\Api\Interfaces\ForumRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
     }
 
     public function testReplaceShouldReturnErrorWhenSettingFirstOrderErrored(): void
     {
         $this->transaction->expects(self::once())->method('rollBack');
+        $this->logger->expects(self::once())->method('log')->with(
+            self::callback(
+                static function (array $data) {
+                    return 3 === count($data)
+                        && 'Exception while replacing forums order' === $data[0]
+                        && 'Error while setting new forum order!' === $data[1];
+                }
+            ),
+            1,
+            'podium'
+        );
 
-        $forum = $this->createMock(ForumRepositoryInterface::class);
-        $forum->method('getOrder')->willReturn(1);
-        $forum->method('setOrder')->willReturn(false);
-        $result = $this->service->replace($forum, $forum);
+        $forum1 = $this->createMock(ForumRepositoryInterface::class);
+        $forum1->method('getOrder')->willReturn(1);
+        $forum1->method('setOrder')->willReturn(false);
+        $forum2 = $this->createMock(ForumRepositoryInterface::class);
+        $forum2->method('getOrder')->willReturn(2);
+        $forum2->method('setOrder')->willReturn(true);
+        $result = $this->service->replace($forum1, $forum2);
 
         self::assertFalse($result->getResult());
+        self::assertSame('Error while setting new forum order!', $result->getErrors()['exception']->getMessage());
     }
 
     public function testReplaceShouldReturnErrorWhenSettingSecondOrderErrored(): void
     {
         $this->transaction->expects(self::once())->method('rollBack');
+        $this->logger->expects(self::once())->method('log')->with(
+            self::callback(
+                static function (array $data) {
+                    return 3 === count($data)
+                        && 'Exception while replacing forums order' === $data[0]
+                        && 'Error while setting new forum order!' === $data[1];
+                }
+            ),
+            1,
+            'podium'
+        );
 
         $forum1 = $this->createMock(ForumRepositoryInterface::class);
         $forum1->method('getOrder')->willReturn(1);
@@ -67,6 +99,7 @@ public function testReplaceShouldReturnErrorWhenSettingSecondOrderErrored(): voi
         $result = $this->service->replace($forum1, $forum2);
 
         self::assertFalse($result->getResult());
+        self::assertSame('Error while setting new forum order!', $result->getErrors()['exception']->getMessage());
     }
 
     public function testReplaceShouldReturnSuccessWhenReplacingIsDone(): void
@@ -105,6 +138,17 @@ static function (array $data) {
         self::assertSame('exc', $result->getErrors()['exception']->getMessage());
     }
 
+    public function testSortShouldReturnErrorWhenRepositoryIsWrong(): void
+    {
+        $result = $this->service->sort($this->createMock(RepositoryInterface::class));
+
+        self::assertFalse($result->getResult());
+        self::assertSame(
+            'Forum must be instance of Podium\Api\Interfaces\ForumRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
+    }
+
     public function testSortShouldReturnErrorWhenSortingErrored(): void
     {
         $this->transaction->expects(self::once())->method('rollBack');
diff --git a/tests/Unit/Group/GroupBuilderTest.php b/tests/Unit/Group/GroupBuilderTest.php
index 1ae17e1..9fbe68d 100644
--- a/tests/Unit/Group/GroupBuilderTest.php
+++ b/tests/Unit/Group/GroupBuilderTest.php
@@ -38,7 +38,10 @@ public function testCreateShouldReturnErrorWhenRepositoryIsWrong(): void
         $result = $this->service->create($this->createMock(RepositoryInterface::class));
 
         self::assertFalse($result->getResult());
-        self::assertEmpty($result->getErrors());
+        self::assertSame(
+            'Group must be instance of Podium\Api\Interfaces\GroupRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
     }
 
     public function testCreateShouldReturnSuccessWhenCreatingIsDone(): void
@@ -91,7 +94,10 @@ public function testEditShouldReturnErrorWhenRepositoryIsWrong(): void
         $result = $this->service->edit($this->createMock(RepositoryInterface::class));
 
         self::assertFalse($result->getResult());
-        self::assertEmpty($result->getErrors());
+        self::assertSame(
+            'Group must be instance of Podium\Api\Interfaces\GroupRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
     }
 
     public function testEditShouldReturnSuccessWhenEditingIsDone(): void
diff --git a/tests/Unit/Group/GroupRemoverTest.php b/tests/Unit/Group/GroupRemoverTest.php
index 564e6c7..abbd524 100644
--- a/tests/Unit/Group/GroupRemoverTest.php
+++ b/tests/Unit/Group/GroupRemoverTest.php
@@ -25,7 +25,10 @@ public function testRemoveShouldReturnErrorWhenRepositoryIsWrong(): void
         $result = $this->service->remove($this->createMock(RepositoryInterface::class));
 
         self::assertFalse($result->getResult());
-        self::assertEmpty($result->getErrors());
+        self::assertSame(
+            'Group must be instance of Podium\Api\Interfaces\GroupRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
     }
 
     public function testRemoveShouldReturnErrorWhenRemovingErrored(): void
diff --git a/tests/Unit/Logger/LoggerRemoverTest.php b/tests/Unit/Logger/LoggerRemoverTest.php
index 37bfd81..b73f1c7 100644
--- a/tests/Unit/Logger/LoggerRemoverTest.php
+++ b/tests/Unit/Logger/LoggerRemoverTest.php
@@ -25,7 +25,10 @@ public function testRemoveShouldReturnErrorWhenRepositoryIsWrong(): void
         $result = $this->service->remove($this->createMock(RepositoryInterface::class));
 
         self::assertFalse($result->getResult());
-        self::assertEmpty($result->getErrors());
+        self::assertSame(
+            'Log must be instance of Podium\Api\Interfaces\LogRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
     }
 
     public function testRemoveShouldReturnErrorWhenRemovingErrored(): void
diff --git a/tests/Unit/Member/MemberRemoverTest.php b/tests/Unit/Member/MemberRemoverTest.php
index 0af1134..dc09083 100644
--- a/tests/Unit/Member/MemberRemoverTest.php
+++ b/tests/Unit/Member/MemberRemoverTest.php
@@ -25,7 +25,10 @@ public function testRemoveShouldReturnErrorWhenRepositoryIsWrong(): void
         $result = $this->service->remove($this->createMock(RepositoryInterface::class));
 
         self::assertFalse($result->getResult());
-        self::assertEmpty($result->getErrors());
+        self::assertSame(
+            'Member must be instance of Podium\Api\Interfaces\MemberRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
     }
 
     public function testRemoveShouldReturnErrorWhenRemovingErrored(): void
diff --git a/tests/Unit/Poll/PollRemoverTest.php b/tests/Unit/Poll/PollRemoverTest.php
index 604dc54..2ba7d59 100644
--- a/tests/Unit/Poll/PollRemoverTest.php
+++ b/tests/Unit/Poll/PollRemoverTest.php
@@ -26,7 +26,10 @@ public function testRemoveShouldReturnErrorWhenRepositoryIsWrong(): void
         $result = $this->service->remove($this->createMock(RepositoryInterface::class));
 
         self::assertFalse($result->getResult());
-        self::assertEmpty($result->getErrors());
+        self::assertSame(
+            'Post must be instance of Podium\Api\Interfaces\PollPostRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
     }
 
     public function testRemoveShouldReturnErrorWhenRemovingErrored(): void
diff --git a/tests/Unit/Post/PostArchiverTest.php b/tests/Unit/Post/PostArchiverTest.php
index 1845b4a..38ce043 100644
--- a/tests/Unit/Post/PostArchiverTest.php
+++ b/tests/Unit/Post/PostArchiverTest.php
@@ -25,7 +25,10 @@ public function testArchiveShouldReturnErrorWhenRepositoryIsWrong(): void
         $result = $this->service->archive($this->createMock(RepositoryInterface::class));
 
         self::assertFalse($result->getResult());
-        self::assertEmpty($result->getErrors());
+        self::assertSame(
+            'Post must be instance of Podium\Api\Interfaces\PostRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
     }
 
     public function testArchiveShouldReturnErrorWhenArchivingErrored(): void
@@ -93,7 +96,10 @@ public function testReviveShouldReturnErrorWhenRepositoryIsWrong(): void
         $result = $this->service->revive($this->createMock(RepositoryInterface::class));
 
         self::assertFalse($result->getResult());
-        self::assertEmpty($result->getErrors());
+        self::assertSame(
+            'Post must be instance of Podium\Api\Interfaces\PostRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
     }
 
     public function testReviveShouldReturnErrorWhenRevivingErrored(): void
diff --git a/tests/Unit/Post/PostBuilderTest.php b/tests/Unit/Post/PostBuilderTest.php
index 753c6a2..0e1e91c 100644
--- a/tests/Unit/Post/PostBuilderTest.php
+++ b/tests/Unit/Post/PostBuilderTest.php
@@ -23,15 +23,34 @@ protected function setUp(): void
         $this->service = new PostBuilder();
     }
 
-    public function testCreateShouldReturnErrorWhenRepositoryIsWrong(): void
+    public function testCreateShouldReturnErrorWhenPostRepositoryIsWrong(): void
     {
         $result = $this->service->create(
             $this->createMock(RepositoryInterface::class),
             $this->createMock(MemberRepositoryInterface::class),
+            $this->createMock(ThreadRepositoryInterface::class)
+        );
+
+        self::assertFalse($result->getResult());
+        self::assertSame(
+            'Post must be instance of Podium\Api\Interfaces\PostRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
+    }
+
+    public function testCreateShouldReturnErrorWhenThreadRepositoryIsWrong(): void
+    {
+        $result = $this->service->create(
+            $this->createMock(PostRepositoryInterface::class),
+            $this->createMock(MemberRepositoryInterface::class),
             $this->createMock(RepositoryInterface::class)
         );
 
         self::assertFalse($result->getResult());
+        self::assertSame(
+            'Thread must be instance of Podium\Api\Interfaces\ThreadRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
     }
 
     public function testCreateShouldReturnErrorWhenCreatingErrored(): void
@@ -58,9 +77,9 @@ public function testCreateShouldReturnSuccessWhenCreatingIsDone(): void
         $post = $this->createMock(PostRepositoryInterface::class);
         $post->method('create')->willReturn(true);
         $thread = $this->createMock(ThreadRepositoryInterface::class);
-        $thread->method('updateCounters')->willReturn(true);
+        $thread->method('updateCounters')->with(1)->willReturn(true);
         $forum = $this->createMock(ForumRepositoryInterface::class);
-        $forum->method('updateCounters')->willReturn(true);
+        $forum->method('updateCounters')->with(0, 1)->willReturn(true);
         $thread->method('getParent')->willReturn($forum);
         $result = $this->service->create($post, $this->createMock(MemberRepositoryInterface::class), $thread);
 
@@ -128,6 +147,10 @@ public function testEditShouldReturnErrorWhenRepositoryIsWrong(): void
         $result = $this->service->edit($this->createMock(RepositoryInterface::class));
 
         self::assertFalse($result->getResult());
+        self::assertSame(
+            'Post must be instance of Podium\Api\Interfaces\PostRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
     }
 
     public function testEditShouldReturnErrorWhenEditingErrored(): void
diff --git a/tests/Unit/Post/PostLikerTest.php b/tests/Unit/Post/PostLikerTest.php
index 9a7439e..1283f97 100644
--- a/tests/Unit/Post/PostLikerTest.php
+++ b/tests/Unit/Post/PostLikerTest.php
@@ -282,6 +282,7 @@ public function testThumbResetShouldReturnErrorWhenResetErrored(): void
         $thumb = $this->createMock(ThumbRepositoryInterface::class);
         $thumb->method('fetchOne')->willReturn(true);
         $thumb->method('reset')->willReturn(false);
+        $thumb->method('getErrors')->willReturn([2]);
         $result = $this->service->thumbReset(
             $thumb,
             $this->createMock(PostRepositoryInterface::class),
@@ -289,6 +290,7 @@ public function testThumbResetShouldReturnErrorWhenResetErrored(): void
         );
 
         self::assertFalse($result->getResult());
+        self::assertSame([2], $result->getErrors());
     }
 
     public function testThumbResetShouldReturnErrorWhenPostIsNotRated(): void
diff --git a/tests/Unit/Post/PostMoverTest.php b/tests/Unit/Post/PostMoverTest.php
index 39049a4..a06f8ea 100644
--- a/tests/Unit/Post/PostMoverTest.php
+++ b/tests/Unit/Post/PostMoverTest.php
@@ -30,7 +30,10 @@ public function testMoveShouldReturnErrorWhenPostRepositoryIsWrong(): void
         );
 
         self::assertFalse($result->getResult());
-        self::assertEmpty($result->getErrors());
+        self::assertSame(
+            'Post must be instance of Podium\Api\Interfaces\PostRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
     }
 
     public function testMoveShouldReturnErrorWhenThreadRepositoryIsWrong(): void
@@ -41,7 +44,10 @@ public function testMoveShouldReturnErrorWhenThreadRepositoryIsWrong(): void
         );
 
         self::assertFalse($result->getResult());
-        self::assertEmpty($result->getErrors());
+        self::assertSame(
+            'Thread must be instance of Podium\Api\Interfaces\ThreadRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
     }
 
     public function testMoveShouldReturnErrorWhenMovingErrored(): void
@@ -60,15 +66,21 @@ public function testMoveShouldReturnSuccessWhenMovingIsDone(): void
     {
         $this->transaction->expects(self::once())->method('commit');
 
+        $oldForum = $this->createMock(ForumRepositoryInterface::class);
+        $oldForum->method('updateCounters')->with(0, -1)->willReturn(true);
+        $oldThread = $this->createMock(ThreadRepositoryInterface::class);
+        $oldThread->method('updateCounters')->with(-1)->willReturn(true);
+        $oldThread->method('getParent')->willReturn($oldForum);
         $post = $this->createMock(PostRepositoryInterface::class);
         $post->method('move')->willReturn(true);
-        $thread = $this->createMock(ThreadRepositoryInterface::class);
-        $thread->method('updateCounters')->willReturn(true);
-        $forum = $this->createMock(ForumRepositoryInterface::class);
-        $forum->method('updateCounters')->willReturn(true);
-        $thread->method('getParent')->willReturn($forum);
-        $post->method('getParent')->willReturn($thread);
-        $result = $this->service->move($post, $thread);
+        $post->method('getParent')->willReturn($oldThread);
+
+        $newForum = $this->createMock(ForumRepositoryInterface::class);
+        $newForum->method('updateCounters')->with(0, 1)->willReturn(true);
+        $newThread = $this->createMock(ThreadRepositoryInterface::class);
+        $newThread->method('updateCounters')->with(1)->willReturn(true);
+        $newThread->method('getParent')->willReturn($newForum);
+        $result = $this->service->move($post, $newThread);
 
         self::assertTrue($result->getResult());
     }
diff --git a/tests/Unit/Post/PostPinnerTest.php b/tests/Unit/Post/PostPinnerTest.php
index 8ec396a..d37a1ac 100644
--- a/tests/Unit/Post/PostPinnerTest.php
+++ b/tests/Unit/Post/PostPinnerTest.php
@@ -25,7 +25,10 @@ public function testPinShouldReturnErrorWhenPostRepositoryIsWrong(): void
         $result = $this->service->pin($this->createMock(RepositoryInterface::class));
 
         self::assertFalse($result->getResult());
-        self::assertEmpty($result->getErrors());
+        self::assertSame(
+            'Post must be instance of Podium\Api\Interfaces\PostRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
     }
 
     public function testPinShouldReturnErrorWhenPinningErrored(): void
@@ -78,7 +81,10 @@ public function testUnpinShouldReturnErrorWhenPostRepositoryIsWrong(): void
         $result = $this->service->unpin($this->createMock(RepositoryInterface::class));
 
         self::assertFalse($result->getResult());
-        self::assertEmpty($result->getErrors());
+        self::assertSame(
+            'Post must be instance of Podium\Api\Interfaces\PostRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
     }
 
     public function testUnpinShouldReturnErrorWhenUnpinningErrored(): void
diff --git a/tests/Unit/Post/PostRemoverTest.php b/tests/Unit/Post/PostRemoverTest.php
index 6a4e228..5ed2dd9 100644
--- a/tests/Unit/Post/PostRemoverTest.php
+++ b/tests/Unit/Post/PostRemoverTest.php
@@ -27,7 +27,10 @@ public function testRemoveShouldReturnErrorWhenRepositoryIsWrong(): void
         $result = $this->service->remove($this->createMock(RepositoryInterface::class));
 
         self::assertFalse($result->getResult());
-        self::assertEmpty($result->getErrors());
+        self::assertSame(
+            'Post must be instance of Podium\Api\Interfaces\PostRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
     }
 
     public function testRemoveShouldReturnErrorWhenRemovingErrored(): void
@@ -64,9 +67,9 @@ public function testRemoveShouldReturnSuccessWhenRemovingIsDone(): void
         $post->method('isArchived')->willReturn(true);
         $post->method('delete')->willReturn(true);
         $thread = $this->createMock(ThreadRepositoryInterface::class);
-        $thread->method('updateCounters')->willReturn(true);
+        $thread->method('updateCounters')->with(-1)->willReturn(true);
         $forum = $this->createMock(ForumRepositoryInterface::class);
-        $forum->method('updateCounters')->willReturn(true);
+        $forum->method('updateCounters')->with(0, -1)->willReturn(true);
         $thread->method('getParent')->willReturn($forum);
         $post->method('getParent')->willReturn($thread);
         $result = $this->service->remove($post);
diff --git a/tests/Unit/Rank/RankBuilderTest.php b/tests/Unit/Rank/RankBuilderTest.php
index 84d4db8..8667b90 100644
--- a/tests/Unit/Rank/RankBuilderTest.php
+++ b/tests/Unit/Rank/RankBuilderTest.php
@@ -38,7 +38,10 @@ public function testCreateShouldReturnErrorWhenRepositoryIsWrong(): void
         $result = $this->service->create($this->createMock(RepositoryInterface::class));
 
         self::assertFalse($result->getResult());
-        self::assertEmpty($result->getErrors());
+        self::assertSame(
+            'Rank must be instance of Podium\Api\Interfaces\RankRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
     }
 
     public function testCreateShouldReturnSuccessWhenCreatingIsDone(): void
@@ -91,7 +94,10 @@ public function testEditShouldReturnErrorWhenRepositoryIsWrong(): void
         $result = $this->service->edit($this->createMock(RepositoryInterface::class));
 
         self::assertFalse($result->getResult());
-        self::assertEmpty($result->getErrors());
+        self::assertSame(
+            'Rank must be instance of Podium\Api\Interfaces\RankRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
     }
 
     public function testEditShouldReturnSuccessWhenEditingIsDone(): void
diff --git a/tests/Unit/Rank/RankRemoverTest.php b/tests/Unit/Rank/RankRemoverTest.php
index 689fe31..818368a 100644
--- a/tests/Unit/Rank/RankRemoverTest.php
+++ b/tests/Unit/Rank/RankRemoverTest.php
@@ -25,7 +25,10 @@ public function testRemoveShouldReturnErrorWhenRepositoryIsWrong(): void
         $result = $this->service->remove($this->createMock(RepositoryInterface::class));
 
         self::assertFalse($result->getResult());
-        self::assertEmpty($result->getErrors());
+        self::assertSame(
+            'Rank must be instance of Podium\Api\Interfaces\RankRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
     }
 
     public function testRemoveShouldReturnErrorWhenRemovingErrored(): void
diff --git a/tests/Unit/ServiceExceptionTest.php b/tests/Unit/ServiceExceptionTest.php
index 07c20e1..cd75785 100644
--- a/tests/Unit/ServiceExceptionTest.php
+++ b/tests/Unit/ServiceExceptionTest.php
@@ -4,6 +4,7 @@
 
 namespace Podium\Tests\Unit;
 
+use Exception;
 use PHPUnit\Framework\TestCase;
 use Podium\Api\Services\ServiceException;
 
@@ -20,4 +21,23 @@ public function testErrorList(): void
 
         self::assertSame([1], $exc->getErrorList());
     }
+
+    public function testDefaults(): void
+    {
+        $exc = new ServiceException();
+
+        self::assertSame([], $exc->getErrorList());
+        self::assertSame('', $exc->getMessage());
+        self::assertSame(0, $exc->getCode());
+        self::assertNull($exc->getPrevious());
+    }
+
+    public function testExceptionArguments(): void
+    {
+        $exc = new ServiceException([], 'test', 2, new Exception());
+
+        self::assertSame('test', $exc->getMessage());
+        self::assertSame(2, $exc->getCode());
+        self::assertNotNull($exc->getPrevious());
+    }
 }
diff --git a/tests/Unit/Thread/ThreadArchiverTest.php b/tests/Unit/Thread/ThreadArchiverTest.php
index 82de65f..37e610c 100644
--- a/tests/Unit/Thread/ThreadArchiverTest.php
+++ b/tests/Unit/Thread/ThreadArchiverTest.php
@@ -25,7 +25,10 @@ public function testArchiveShouldReturnErrorWhenRepositoryIsWrong(): void
         $result = $this->service->archive($this->createMock(RepositoryInterface::class));
 
         self::assertFalse($result->getResult());
-        self::assertEmpty($result->getErrors());
+        self::assertSame(
+            'Thread must be instance of Podium\Api\Interfaces\ThreadRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
     }
 
     public function testArchiveShouldReturnErrorWhenArchivingErrored(): void
@@ -93,7 +96,10 @@ public function testReviveShouldReturnErrorWhenRepositoryIsWrong(): void
         $result = $this->service->revive($this->createMock(RepositoryInterface::class));
 
         self::assertFalse($result->getResult());
-        self::assertEmpty($result->getErrors());
+        self::assertSame(
+            'Thread must be instance of Podium\Api\Interfaces\ThreadRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
     }
 
     public function testReviveShouldReturnErrorWhenRevivingErrored(): void
@@ -110,6 +116,18 @@ public function testReviveShouldReturnErrorWhenRevivingErrored(): void
         self::assertSame([1], $result->getErrors());
     }
 
+    public function testReviveShouldReturnErrorWhenThreadIsNotArchived(): void
+    {
+        $this->transaction->expects(self::once())->method('rollBack');
+
+        $thread = $this->createMock(ThreadRepositoryInterface::class);
+        $thread->method('isArchived')->willReturn(false);
+        $result = $this->service->revive($thread);
+
+        self::assertFalse($result->getResult());
+        self::assertSame('thread.not.archived', $result->getErrors()['api']);
+    }
+
     public function testReviveShouldReturnSuccessWhenRevivingIsDone(): void
     {
         $this->transaction->expects(self::once())->method('commit');
diff --git a/tests/Unit/Thread/ThreadBookmarkerTest.php b/tests/Unit/Thread/ThreadBookmarkerTest.php
index a67e75c..c982d5d 100644
--- a/tests/Unit/Thread/ThreadBookmarkerTest.php
+++ b/tests/Unit/Thread/ThreadBookmarkerTest.php
@@ -60,6 +60,25 @@ public function testMarkShouldReturnTrueIfBookmarkIsSeenAfterPostCreation(): voi
         self::assertTrue($result->getResult());
     }
 
+    public function testMarkShouldReturnTrueIfBookmarkIsSeenAtTheTimeOfPostCreation(): void
+    {
+        $this->transaction->expects(self::once())->method('commit');
+
+        $bookmark = $this->createMock(BookmarkRepositoryInterface::class);
+        $bookmark->method('fetchOne')->willReturn(true);
+        $bookmark->expects(self::never())->method('prepare');
+        $bookmark->method('getLastSeen')->willReturn(2);
+        $bookmark->expects(self::never())->method('mark');
+
+        $post = $this->createMock(PostRepositoryInterface::class);
+        $post->method('getParent')->willReturn($this->createMock(ThreadRepositoryInterface::class));
+        $post->method('getCreatedAt')->willReturn(2);
+
+        $result = $this->service->mark($bookmark, $post, $this->createMock(MemberRepositoryInterface::class));
+
+        self::assertTrue($result->getResult());
+    }
+
     public function testMarkShouldPrepareBookmarkWhenItDoesntExist(): void
     {
         $this->transaction->expects(self::once())->method('commit');
@@ -79,6 +98,26 @@ public function testMarkShouldPrepareBookmarkWhenItDoesntExist(): void
         self::assertTrue($result->getResult());
     }
 
+    public function testMarkShouldReturnErrorWhenMarkingErrored(): void
+    {
+        $this->transaction->expects(self::once())->method('rollBack');
+
+        $bookmark = $this->createMock(BookmarkRepositoryInterface::class);
+        $bookmark->method('fetchOne')->willReturn(true);
+        $bookmark->method('getLastSeen')->willReturn(1);
+        $bookmark->method('mark')->willReturn(false);
+        $bookmark->method('getErrors')->willReturn([3]);
+
+        $post = $this->createMock(PostRepositoryInterface::class);
+        $post->method('getParent')->willReturn($this->createMock(ThreadRepositoryInterface::class));
+        $post->method('getCreatedAt')->willReturn(2);
+
+        $result = $this->service->mark($bookmark, $post, $this->createMock(MemberRepositoryInterface::class));
+
+        self::assertFalse($result->getResult());
+        self::assertSame([3], $result->getErrors());
+    }
+
     public function testMarkShouldReturnErrorWhenMarkingThrowsException(): void
     {
         $this->transaction->expects(self::once())->method('rollBack');
diff --git a/tests/Unit/Thread/ThreadBuilderTest.php b/tests/Unit/Thread/ThreadBuilderTest.php
index 20f2811..e70e00a 100644
--- a/tests/Unit/Thread/ThreadBuilderTest.php
+++ b/tests/Unit/Thread/ThreadBuilderTest.php
@@ -22,15 +22,34 @@ protected function setUp(): void
         $this->service = new ThreadBuilder();
     }
 
-    public function testCreateShouldReturnErrorWhenRepositoryIsWrong(): void
+    public function testCreateShouldReturnErrorWhenThreadRepositoryIsWrong(): void
     {
         $result = $this->service->create(
             $this->createMock(RepositoryInterface::class),
             $this->createMock(MemberRepositoryInterface::class),
+            $this->createMock(ForumRepositoryInterface::class)
+        );
+
+        self::assertFalse($result->getResult());
+        self::assertSame(
+            'Thread must be instance of Podium\Api\Interfaces\ThreadRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
+    }
+
+    public function testCreateShouldReturnErrorWhenForumRepositoryIsWrong(): void
+    {
+        $result = $this->service->create(
+            $this->createMock(ThreadRepositoryInterface::class),
+            $this->createMock(MemberRepositoryInterface::class),
             $this->createMock(RepositoryInterface::class)
         );
 
         self::assertFalse($result->getResult());
+        self::assertSame(
+            'Forum must be instance of Podium\Api\Interfaces\ForumRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
     }
 
     public function testCreateShouldReturnErrorWhenCreatingErrored(): void
@@ -57,7 +76,7 @@ public function testCreateShouldReturnSuccessWhenCreatingIsDone(): void
         $thread = $this->createMock(ThreadRepositoryInterface::class);
         $thread->method('create')->willReturn(true);
         $forum = $this->createMock(ForumRepositoryInterface::class);
-        $forum->method('updateCounters')->willReturn(true);
+        $forum->method('updateCounters')->with(1, 0)->willReturn(true);
         $result = $this->service->create($thread, $this->createMock(MemberRepositoryInterface::class), $forum);
 
         self::assertTrue($result->getResult());
@@ -118,6 +137,10 @@ public function testEditShouldReturnErrorWhenRepositoryIsWrong(): void
         $result = $this->service->edit($this->createMock(RepositoryInterface::class));
 
         self::assertFalse($result->getResult());
+        self::assertSame(
+            'Thread must be instance of Podium\Api\Interfaces\ThreadRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
     }
 
     public function testEditShouldReturnErrorWhenEditingErrored(): void
diff --git a/tests/Unit/Thread/ThreadMoverTest.php b/tests/Unit/Thread/ThreadMoverTest.php
index 0048898..3201cf5 100644
--- a/tests/Unit/Thread/ThreadMoverTest.php
+++ b/tests/Unit/Thread/ThreadMoverTest.php
@@ -29,7 +29,10 @@ public function testMoveShouldReturnErrorWhenThreadRepositoryIsWrong(): void
         );
 
         self::assertFalse($result->getResult());
-        self::assertEmpty($result->getErrors());
+        self::assertSame(
+            'Thread must be instance of Podium\Api\Interfaces\ThreadRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
     }
 
     public function testMoveShouldReturnErrorWhenForumRepositoryIsWrong(): void
@@ -40,7 +43,10 @@ public function testMoveShouldReturnErrorWhenForumRepositoryIsWrong(): void
         );
 
         self::assertFalse($result->getResult());
-        self::assertEmpty($result->getErrors());
+        self::assertSame(
+            'Forum must be instance of Podium\Api\Interfaces\ForumRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
     }
 
     public function testMoveShouldReturnErrorWhenMovingErrored(): void
@@ -61,11 +67,15 @@ public function testMoveShouldReturnSuccessWhenMovingIsDone(): void
 
         $thread = $this->createMock(ThreadRepositoryInterface::class);
         $thread->method('move')->willReturn(true);
-        $forum = $this->createMock(ForumRepositoryInterface::class);
-        $forum->method('updateCounters')->willReturn(true);
-        $thread->method('getParent')->willReturn($forum);
+        $thread->method('getPostsCount')->willReturn(9);
+        $newForum = $this->createMock(ForumRepositoryInterface::class);
+        $newForum->method('updateCounters')->with(1, 9)->willReturn(true);
+
+        $oldForum = $this->createMock(ForumRepositoryInterface::class);
+        $oldForum->method('updateCounters')->with(-1, -9)->willReturn(true);
+        $thread->method('getParent')->willReturn($oldForum);
         $thread->method('updateCounters')->willReturn(true);
-        $result = $this->service->move($thread, $forum);
+        $result = $this->service->move($thread, $newForum);
 
         self::assertTrue($result->getResult());
     }
diff --git a/tests/Unit/Thread/ThreadPinnerTest.php b/tests/Unit/Thread/ThreadPinnerTest.php
index c50d0a7..91bc490 100644
--- a/tests/Unit/Thread/ThreadPinnerTest.php
+++ b/tests/Unit/Thread/ThreadPinnerTest.php
@@ -25,7 +25,10 @@ public function testPinShouldReturnErrorWhenThreadRepositoryIsWrong(): void
         $result = $this->service->pin($this->createMock(RepositoryInterface::class));
 
         self::assertFalse($result->getResult());
-        self::assertEmpty($result->getErrors());
+        self::assertSame(
+            'Thread must be instance of Podium\Api\Interfaces\ThreadRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
     }
 
     public function testPinShouldReturnErrorWhenPinningErrored(): void
@@ -78,7 +81,10 @@ public function testUnpinShouldReturnErrorWhenThreadRepositoryIsWrong(): void
         $result = $this->service->unpin($this->createMock(RepositoryInterface::class));
 
         self::assertFalse($result->getResult());
-        self::assertEmpty($result->getErrors());
+        self::assertSame(
+            'Thread must be instance of Podium\Api\Interfaces\ThreadRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
     }
 
     public function testUnpinShouldReturnErrorWhenUnpinningErrored(): void
diff --git a/tests/Unit/Thread/ThreadRemoverTest.php b/tests/Unit/Thread/ThreadRemoverTest.php
index bda19b4..9d5406b 100644
--- a/tests/Unit/Thread/ThreadRemoverTest.php
+++ b/tests/Unit/Thread/ThreadRemoverTest.php
@@ -26,7 +26,10 @@ public function testRemoveShouldReturnErrorWhenRepositoryIsWrong(): void
         $result = $this->service->remove($this->createMock(RepositoryInterface::class));
 
         self::assertFalse($result->getResult());
-        self::assertEmpty($result->getErrors());
+        self::assertSame(
+            'Thread must be instance of Podium\Api\Interfaces\ThreadRepositoryInterface!',
+            $result->getErrors()['exception']->getMessage()
+        );
     }
 
     public function testRemoveShouldReturnErrorWhenRemovingErrored(): void
@@ -62,8 +65,9 @@ public function testRemoveShouldReturnSuccessWhenRemovingIsDone(): void
         $thread = $this->createMock(ThreadRepositoryInterface::class);
         $thread->method('isArchived')->willReturn(true);
         $thread->method('delete')->willReturn(true);
+        $thread->method('getPostsCount')->willReturn(1);
         $forum = $this->createMock(ForumRepositoryInterface::class);
-        $forum->method('updateCounters')->willReturn(true);
+        $forum->method('updateCounters')->with(-1, -1)->willReturn(true);
         $thread->method('getParent')->willReturn($forum);
         $result = $this->service->remove($thread);