diff --git a/actions/class.Runner.php b/actions/class.Runner.php
index b29028c452..dcc1d2b7f3 100644
--- a/actions/class.Runner.php
+++ b/actions/class.Runner.php
@@ -47,6 +47,7 @@
 use oat\taoQtiTest\model\Service\TimeoutService;
 use oat\taoQtiTest\model\Service\ToolsStateAwareInterface;
 use oat\taoQtiTest\models\cat\CatEngineNotFoundException;
+use oat\taoQtiTest\models\classes\runner\QtiRunnerInvalidResponsesException;
 use oat\taoQtiTest\models\container\QtiTestDeliveryContainer;
 use oat\taoQtiTest\models\runner\communicator\CommunicationService;
 use oat\taoQtiTest\models\runner\communicator\QtiCommunicationService;
@@ -274,6 +275,7 @@ protected function getStatusCodeFromException(Exception $exception): int
             case QtiRunnerEmptyResponsesException::class:
             case QtiRunnerClosedException::class:
             case QtiRunnerPausedException::class:
+            case QtiRunnerInvalidResponsesException::class:
                 return 200;
 
             case common_exception_NotImplemented::class:
diff --git a/composer.json b/composer.json
index d372dfb62e..de8b58e894 100644
--- a/composer.json
+++ b/composer.json
@@ -62,7 +62,7 @@
     "ext-zip": "*",
     "oat-sa/lib-test-cat": "2.4.0",
     "oat-sa/oatbox-extension-installer": "~1.1||dev-master",
-    "qtism/qtism": ">=0.28.3",
+    "qtism/qtism": ">=0.28.7",
     "oat-sa/generis": ">=16.0.0",
     "oat-sa/tao-core": ">=54.27.0",
     "oat-sa/extension-tao-item": ">=12.4.0",
diff --git a/model/Container/TestQtiServiceProvider.php b/model/Container/TestQtiServiceProvider.php
index f1a482c501..830a3d3c1b 100644
--- a/model/Container/TestQtiServiceProvider.php
+++ b/model/Container/TestQtiServiceProvider.php
@@ -34,6 +34,7 @@
 use oat\taoQtiTest\model\Domain\Model\QtiTestRepositoryInterface;
 use oat\taoQtiTest\model\Domain\Model\ToolsStateRepositoryInterface;
 use oat\taoQtiTest\model\Infrastructure\QtiItemResponseRepository;
+use oat\taoQtiTest\model\Infrastructure\QtiItemResponseValidator;
 use oat\taoQtiTest\model\Infrastructure\QtiToolsStateRepository;
 use oat\taoQtiTest\model\Infrastructure\QtiTestRepository;
 use oat\taoQtiTest\model\Service\ConcurringSessionService;
@@ -41,6 +42,7 @@
 use oat\taoQtiTest\model\Service\ListItemsService;
 use oat\taoQtiTest\model\Service\MoveService;
 use oat\taoQtiTest\model\Service\PauseService;
+use oat\taoQtiTest\model\Service\PluginManagerService;
 use oat\taoQtiTest\model\Service\SkipService;
 use oat\taoQtiTest\model\Service\StoreTraceVariablesService;
 use oat\taoQtiTest\model\Service\TimeoutService;
@@ -49,6 +51,7 @@
 use oat\taoQtiTest\models\TestModelService;
 use oat\taoQtiTest\models\TestSessionService;
 use Symfony\Component\DependencyInjection\Loader\Configurator\ContainerConfigurator;
+use common_ext_ExtensionsManager as ExtensionsManager;
 
 use function Symfony\Component\DependencyInjection\Loader\Configurator\service;
 
@@ -63,7 +66,9 @@ public function __invoke(ContainerConfigurator $configurator): void
             ->public()
             ->args(
                 [
-                    service(QtiRunnerService::SERVICE_ID)
+                    service(QtiRunnerService::SERVICE_ID),
+                    service(FeatureFlagChecker::class),
+                    service(QtiItemResponseValidator::class),
                 ]
             );
 
@@ -176,5 +181,19 @@ public function __invoke(ContainerConfigurator $configurator): void
                     service(TimerAdjustmentServiceInterface::SERVICE_ID),
                 ]
             );
+
+        $services
+            ->set(QtiItemResponseValidator::class, QtiItemResponseValidator::class)
+            ->public();
+
+        $services
+            ->set(PluginManagerService::class, PluginManagerService::class)
+            ->args(
+                [
+                    service(Ontology::SERVICE_ID),
+                    service(ExtensionsManager::SERVICE_ID),
+                ]
+            )
+            ->public();
     }
 }
diff --git a/model/Infrastructure/QtiItemResponseRepository.php b/model/Infrastructure/QtiItemResponseRepository.php
index da359db323..5f5d4abd2b 100644
--- a/model/Infrastructure/QtiItemResponseRepository.php
+++ b/model/Infrastructure/QtiItemResponseRepository.php
@@ -24,22 +24,32 @@
 
 namespace oat\taoQtiTest\model\Infrastructure;
 
+use oat\tao\model\featureFlag\FeatureFlagChecker;
 use oat\taoQtiTest\model\Domain\Model\ItemResponse;
 use oat\taoQtiTest\model\Domain\Model\ItemResponseRepositoryInterface;
+use oat\taoQtiTest\models\classes\runner\QtiRunnerInvalidResponsesException;
 use oat\taoQtiTest\models\runner\QtiRunnerEmptyResponsesException;
 use oat\taoQtiTest\models\runner\QtiRunnerItemResponseException;
 use oat\taoQtiTest\models\runner\QtiRunnerService;
 use oat\taoQtiTest\models\runner\RunnerServiceContext;
+use qtism\runtime\tests\AssessmentItemSessionException;
 use taoQtiTest_helpers_TestRunnerUtils as TestRunnerUtils;
 
 class QtiItemResponseRepository implements ItemResponseRepositoryInterface
 {
     /** @var QtiRunnerService */
     private $runnerService;
-
-    public function __construct(QtiRunnerService $runnerService)
-    {
+    private FeatureFlagChecker $featureFlagChecker;
+    private QtiItemResponseValidator $itemResponseValidator;
+
+    public function __construct(
+        QtiRunnerService $runnerService,
+        FeatureFlagChecker $featureFlagChecker,
+        QtiItemResponseValidator $itemResponseValidator
+    ) {
         $this->runnerService = $runnerService;
+        $this->featureFlagChecker = $featureFlagChecker;
+        $this->itemResponseValidator = $itemResponseValidator;
     }
 
     public function save(ItemResponse $itemResponse, RunnerServiceContext $serviceContext): void
@@ -110,6 +120,17 @@ private function saveItemResponses(ItemResponse $itemResponse, RunnerServiceCont
             $itemResponse->getResponse()
         );
 
+        if ($this->featureFlagChecker->isEnabled('FEATURE_FLAG_RESPONSE_VALIDATOR')) {
+            try {
+                $this->itemResponseValidator->validate($serviceContext->getTestSession(), $responses);
+            } catch (AssessmentItemSessionException $e) {
+                throw new QtiRunnerInvalidResponsesException($e->getMessage());
+            }
+
+            $this->runnerService->storeItemResponse($serviceContext, $itemDefinition, $responses);
+            return;
+        }
+
         if (
             $this->runnerService->getTestConfig()->getConfigValue('enableAllowSkipping')
             && !TestRunnerUtils::doesAllowSkipping($serviceContext->getTestSession())
diff --git a/model/Infrastructure/QtiItemResponseValidator.php b/model/Infrastructure/QtiItemResponseValidator.php
new file mode 100644
index 0000000000..3cfb136199
--- /dev/null
+++ b/model/Infrastructure/QtiItemResponseValidator.php
@@ -0,0 +1,72 @@
+<?php
+
+/**
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; under version 2
+ * of the License (non-upgradable).
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ *
+ * Copyright (c) 2024 (original work) Open Assessment Technologies SA;
+ */
+
+declare(strict_types=1);
+
+namespace oat\taoQtiTest\model\Infrastructure;
+
+use common_exception_Error;
+use oat\taoQtiTest\models\runner\QtiRunnerEmptyResponsesException;
+use oat\taoQtiTest\models\runner\RunnerServiceContext;
+use qtism\runtime\common\State;
+use qtism\runtime\tests\AssessmentItemSessionException;
+use qtism\runtime\tests\AssessmentTestSession;
+
+class QtiItemResponseValidator
+{
+    /**
+     * @throws AssessmentItemSessionException
+     * @throws common_exception_Error
+     * @throws QtiRunnerEmptyResponsesException
+     */
+    public function validate(AssessmentTestSession $testSession, State $responses): void
+    {
+        if ($this->getAllowSkip($testSession) && $responses->containsNullOnly()) {
+            return;
+        }
+
+        if (!$this->getAllowSkip($testSession) && $responses->containsNullOnly()) {
+            throw new QtiRunnerEmptyResponsesException();
+        }
+
+        if ($this->getResponseValidation($testSession)) {
+            $testSession->getCurrentAssessmentItemSession()
+                ->checkResponseValidityConstraints($responses);
+        }
+    }
+
+    private function getResponseValidation(AssessmentTestSession $testSession): bool
+    {
+        return $testSession->getRoute()
+            ->current()
+            ->getItemSessionControl()
+            ->getItemSessionControl()
+            ->mustValidateResponses();
+    }
+
+    private function getAllowSkip(AssessmentTestSession $testSession): bool
+    {
+        return $testSession->getRoute()
+            ->current()
+            ->getItemSessionControl()
+            ->getItemSessionControl()
+            ->doesAllowSkipping();
+    }
+}
diff --git a/model/Service/PluginManagerService.php b/model/Service/PluginManagerService.php
new file mode 100644
index 0000000000..555f4d0710
--- /dev/null
+++ b/model/Service/PluginManagerService.php
@@ -0,0 +1,92 @@
+<?php
+
+/**
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; under version 2
+ * of the License (non-upgradable).
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ *
+ * Copyright (c) 2024 (original work) Open Assessment Technologies SA;
+ */
+
+declare(strict_types=1);
+
+namespace oat\taoQtiTest\model\Service;
+
+use common_ext_Extension;
+use common_ext_ExtensionsManager as ExtensionsManager;
+use oat\generis\model\data\Ontology;
+use oat\oatbox\reporting\Report;
+
+class PluginManagerService
+{
+    private const PLUGIN_MAP = [
+        'allowSkipping' => 'enable-allow-skipping',
+        'validateResponses' => 'enable-validate-responses',
+    ];
+    private Ontology $ontology;
+    private ExtensionsManager $extensionsManager;
+    private common_ext_Extension $extension;
+    private array $config;
+
+    public function __construct(Ontology $ontology, ExtensionsManager $extensionsManager)
+    {
+        $this->ontology = $ontology;
+        $this->extensionsManager = $extensionsManager;
+        $this->extension = $this->extensionsManager->getExtensionById('taoQtiTest');
+        $this->config = $this->extension->getConfig('testRunner') ?? [];
+    }
+
+    /**
+     * @param string[] $disablePlugins
+     * @param Report $report
+     * @throws \common_exception_Error
+     */
+    public function disablePlugin(array $disablePlugins, Report $report): void
+    {
+        foreach ($disablePlugins as $plugin) {
+            if (array_key_exists($plugin, self::PLUGIN_MAP)) {
+                $report->add(new Report(Report::TYPE_INFO, 'Plugin ' . $plugin . ' has been disabled'));
+                $this->config[self::PLUGIN_MAP[$plugin]] = false;
+            }
+
+            if (array_key_exists($plugin, $this->config)) {
+                $report->add(new Report(Report::TYPE_INFO, 'Plugin ' . $plugin . ' has been disabled'));
+                $this->config[$plugin] = false;
+            }
+        }
+        $this->extension->setConfig('testRunner', $this->config);
+    }
+
+    public function enablePlugin(array $enablePlugins, Report $report): void
+    {
+        $config = $this->getConfig();
+
+        foreach ($enablePlugins as $plugin) {
+            if (array_key_exists($plugin, self::PLUGIN_MAP)) {
+                $report->add(new Report(Report::TYPE_INFO, 'Plugin ' . $plugin . ' has been enabled'));
+                $config[self::PLUGIN_MAP[$plugin]] = true;
+            }
+
+            if (array_key_exists($plugin, $config)) {
+                $report->add(new Report(Report::TYPE_INFO, 'Plugin ' . $plugin . ' has been disabled'));
+                $config[$plugin] = true;
+            }
+        }
+        $this->extension->setConfig('testRunner', $config);
+    }
+
+    private function getConfig(): array
+    {
+        return $this->extensionsManager->getExtensionById('taoQtiTest')->getConfig('testRunner');
+    }
+}
diff --git a/models/classes/runner/QtiRunnerInvalidResponsesException.php b/models/classes/runner/QtiRunnerInvalidResponsesException.php
new file mode 100644
index 0000000000..bf700df7af
--- /dev/null
+++ b/models/classes/runner/QtiRunnerInvalidResponsesException.php
@@ -0,0 +1,37 @@
+<?php
+
+/**
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; under version 2
+ * of the License (non-upgradable).
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ *
+ * Copyright (c) 2024 (original work) Open Assessment Technologies SA ;
+ */
+
+namespace oat\taoQtiTest\models\classes\runner;
+
+use common_Exception;
+use common_exception_UserReadableException;
+
+class QtiRunnerInvalidResponsesException extends common_Exception implements common_exception_UserReadableException
+{
+    public function __construct($message = 'A response to this item is invalid', $code = 200)
+    {
+        parent::__construct($message, $code);
+    }
+
+    public function getUserMessage()
+    {
+        return  __('A response to this item is invalid.');
+    }
+}
diff --git a/models/classes/runner/time/QtiTimeConstraint.php b/models/classes/runner/time/QtiTimeConstraint.php
index abf00371ea..48261123c3 100644
--- a/models/classes/runner/time/QtiTimeConstraint.php
+++ b/models/classes/runner/time/QtiTimeConstraint.php
@@ -231,7 +231,7 @@ private function durationToMs($duration)
      * Serialize the constraint the expected way by the TestContext and the TestMap
      * @return array
      */
-    public function jsonSerialize()
+    public function jsonSerialize(): array
     {
         $source = $this->getSource();
         $timeLimits = $source->getTimeLimits();
@@ -271,6 +271,6 @@ public function jsonSerialize()
                 ];
             }
         }
-        return null;
+        return [];
     }
 }
diff --git a/scripts/tools/TestRunnerPluginManager.php b/scripts/tools/TestRunnerPluginManager.php
new file mode 100644
index 0000000000..a45199d72f
--- /dev/null
+++ b/scripts/tools/TestRunnerPluginManager.php
@@ -0,0 +1,85 @@
+<?php
+
+/**
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; under version 2
+ * of the License (non-upgradable).
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ *
+ * Copyright (c) 2024 (original work) Open Assessment Technologies SA;
+ */
+
+declare(strict_types=1);
+
+namespace oat\taoQtiTest\scripts\tools;
+
+use oat\oatbox\extension\script\ScriptAction;
+use oat\oatbox\reporting\Report;
+use oat\taoQtiTest\model\Service\PluginManagerService;
+
+class TestRunnerPluginManager extends ScriptAction
+{
+    protected function provideOptions()
+    {
+        return [
+            'disablePlugins' => [
+                'prefix' => 'd',
+                'longPrefix' => 'disable',
+                'required' => false,
+                'description' => 'List of plugins to be disabled, separated by comma',
+            ],
+            'enablePlugins' => [
+                'prefix' => 'e',
+                'longPrefix' => 'enable',
+                'required' => false,
+                'description' => 'List of plugins to be enabled, separated by comma',
+            ],
+        ];
+    }
+
+    protected function provideDescription()
+    {
+        return 'Manage test runner plugins';
+    }
+
+    protected function run()
+    {
+        if (empty($this->getOption('disablePlugins')) && empty($this->getOption('enablePlugins'))) {
+            return new Report(Report::TYPE_ERROR, 'No action provided');
+        }
+
+        $report = new Report(Report::TYPE_INFO, 'Plugins have been managed successfully');
+
+        $disablePlugins = $this->getOption('disablePlugins')
+            ? explode(',', $this->getOption('disablePlugins'))
+            : [];
+
+        $enablePlugins = $this->getOption('enablePlugins') !== null
+            ? explode(',', $this->getOption('enablePlugins'))
+            : [];
+
+        if (!empty($disablePlugins)) {
+            $this->getPluiginManagerService()->disablePlugin($disablePlugins, $report);
+        }
+
+        if (!empty($enablePlugins)) {
+            $this->getPluiginManagerService()->enablePlugin($enablePlugins, $report);
+        }
+
+        return $report;
+    }
+
+    private function getPluiginManagerService(): PluginManagerService
+    {
+        return $this->getServiceManager()->getContainer()->get(PluginManagerService::class);
+    }
+}
diff --git a/test/unit/model/Infrastructure/QtiItemResponseRepositoryTest.php b/test/unit/model/Infrastructure/QtiItemResponseRepositoryTest.php
new file mode 100644
index 0000000000..25bfb67110
--- /dev/null
+++ b/test/unit/model/Infrastructure/QtiItemResponseRepositoryTest.php
@@ -0,0 +1,171 @@
+<?php
+
+/**
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; under version 2
+ * of the License (non-upgradable).
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ *
+ * Copyright (c) 2024 (original work) Open Assessment Technologies SA;
+ */
+
+declare(strict_types=1);
+
+namespace oat\taoQtiTest\test\unit\model\Infrastructure;
+
+use oat\tao\model\featureFlag\FeatureFlagChecker;
+use oat\taoQtiTest\model\Domain\Model\ItemResponse;
+use oat\taoQtiTest\model\Infrastructure\QtiItemResponseRepository;
+use oat\taoQtiTest\model\Infrastructure\QtiItemResponseValidator;
+use oat\taoQtiTest\models\classes\runner\QtiRunnerInvalidResponsesException;
+use oat\taoQtiTest\models\runner\QtiRunnerEmptyResponsesException;
+use oat\taoQtiTest\models\runner\QtiRunnerService;
+use oat\taoQtiTest\models\runner\QtiRunnerServiceContext;
+use PHPUnit\Framework\TestCase;
+use qtism\data\ExtendedAssessmentItemRef;
+use qtism\runtime\common\State;
+use qtism\runtime\tests\AssessmentItemSession;
+use qtism\runtime\tests\AssessmentItemSessionException;
+use qtism\runtime\tests\AssessmentTestSession;
+
+class QtiItemResponseRepositoryTest extends TestCase
+{
+    private QtiItemResponseRepository $subject;
+
+    public function setUp(): void
+    {
+        $this->runnerServiceMock = $this->createMock(QtiRunnerService::class);
+        $this->featureFlagCheckerMock = $this->createMock(FeatureFlagChecker::class);
+        $this->itemResponseValidatorMock = $this->createMock(QtiItemResponseValidator::class);
+
+        $this->subject = new QtiItemResponseRepository(
+            $this->runnerServiceMock,
+            $this->featureFlagCheckerMock,
+            $this->itemResponseValidatorMock
+        );
+    }
+
+    /**
+     * @dataProvider saveDataProvider
+     */
+    public function testSave(
+        array $state,
+        array $response,
+        float $duration,
+        float $timestamp,
+        string $itemHref,
+        string $responseIdentifier,
+        int $storeItemResponseCount,
+        bool $shouldThrowException
+    ): void {
+        $itemResponse = new ItemResponse(
+            'itemIdentifier',
+            $state,
+            $response,
+            $duration,
+            $timestamp
+        );
+
+        $runnerServiceContextMock = $this->createMock(QtiRunnerServiceContext::class);
+        $extendedAssessmentItemRefMock = $this->createMock(ExtendedAssessmentItemRef::class);
+        $assessmentItemSession = $this->createMock(AssessmentItemSession::class);
+        $assessmentTestSession = $this->createMock(AssessmentTestSession::class);
+        $stateMock = $this->createMock(State::class);
+
+        $extendedAssessmentItemRefMock->expects($this->once())
+            ->method('getIdentifier')
+            ->willReturn($responseIdentifier);
+
+        $this->runnerServiceMock->expects($this->once())
+            ->method('isTerminated')
+            ->with($runnerServiceContextMock)
+            ->willReturn(false);
+
+        $this->runnerServiceMock->expects($this->once())
+            ->method('endTimer');
+
+        $this->runnerServiceMock->expects($this->once())
+            ->method('getItemHref')
+            ->willReturn($itemHref);
+
+        $this->runnerServiceMock->expects($this->once())
+            ->method('setItemState');
+
+        $runnerServiceContextMock
+            ->method('getCurrentAssessmentItemRef')
+            ->willReturn($extendedAssessmentItemRefMock);
+
+        $this->runnerServiceMock->expects($this->once())
+            ->method('setItemState')
+            ->with($runnerServiceContextMock, $responseIdentifier, $state);
+
+        $this->runnerServiceMock->expects($this->once())
+            ->method('parsesItemResponse')
+            ->willReturn($stateMock);
+
+        $this->featureFlagCheckerMock->expects($this->once())
+            ->method('isEnabled')
+            ->willReturn(true);
+
+        $runnerServiceContextMock
+            ->method('getTestSession')
+            ->willReturn($assessmentTestSession);
+
+        $this->itemResponseValidatorMock->expects($this->once())
+            ->method('validate');
+
+        $this->runnerServiceMock->expects($this->exactly($storeItemResponseCount))
+            ->method('storeItemResponse');
+
+        if ($shouldThrowException) {
+            $this->itemResponseValidatorMock->expects($this->once())
+                ->method('validate')
+                ->with($assessmentTestSession, $stateMock)
+                ->willThrowException(
+                    new AssessmentItemSessionException(
+                        'invalid',
+                        $assessmentItemSession,
+                        AssessmentItemSessionException::DURATION_OVERFLOW
+                    )
+                );
+            $this->expectException(QtiRunnerInvalidResponsesException::class);
+        }
+
+        $this->subject->save($itemResponse, $runnerServiceContextMock);
+    }
+
+    public function saveDataProvider()
+    {
+        return [
+            'happyPath with feature flag enabled' => [
+                'state' => ['state'],
+                'response' => ['response'],
+                'duration' => 1.0,
+                'timestamp' => 2.0,
+                'itemHref' => 'itemHref',
+                'responseIdentifier' => 'itemIdentifier',
+                'storeItemResponseCount' => 1,
+                'shouldThrowException' => false
+            ],
+            'validation throw an error, flag enabled' => [
+                'state' => ['state'],
+                'response' => ['response'],
+                'duration' => 1.0,
+                'timestamp' => 2.0,
+                'itemHref' => 'itemHref',
+                'responseIdentifier' => 'itemIdentifier',
+                'storeItemResponseCount' => 0,
+                'shouldThrowException' => true
+            ]
+        ];
+    }
+}
diff --git a/test/unit/model/Infrastructure/QtiItemResponseValidatorTest.php b/test/unit/model/Infrastructure/QtiItemResponseValidatorTest.php
new file mode 100644
index 0000000000..2941041127
--- /dev/null
+++ b/test/unit/model/Infrastructure/QtiItemResponseValidatorTest.php
@@ -0,0 +1,143 @@
+<?php
+
+/**
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; under version 2
+ * of the License (non-upgradable).
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ *
+ * Copyright (c) 2024 (original work) Open Assessment Technologies SA;
+ */
+
+declare(strict_types=1);
+
+namespace oat\taoQtiTest\test\unit\model\Infrastructure;
+
+use oat\taoQtiTest\model\Infrastructure\QtiItemResponseValidator;
+use oat\taoQtiTest\models\runner\QtiRunnerEmptyResponsesException;
+use PHPUnit\Framework\TestCase;
+use qtism\data\ItemSessionControl;
+use qtism\runtime\common\State;
+use qtism\runtime\tests\AssessmentItemSession;
+use qtism\runtime\tests\AssessmentTestSession;
+use qtism\runtime\tests\Route;
+use qtism\runtime\tests\RouteItem;
+use qtism\runtime\tests\RouteItemSessionControl;
+
+class QtiItemResponseValidatorTest extends TestCase
+{
+    public function setUp(): void
+    {
+        $this->subject = new QtiItemResponseValidator();
+        $this->routeMock = $this->createMock(Route::class);
+        $this->routeItem = $this->createMock(RouteItem::class);
+        $this->routeItemSessionControl = $this->createMock(RouteItemSessionControl::class);
+        $this->itemSessionControl = $this->createMock(ItemSessionControl::class);
+
+        $this->routeMock
+            ->method('current')
+            ->willReturn($this->routeItem);
+
+        $this->routeItem
+            ->method('getItemSessionControl')
+            ->willReturn($this->routeItemSessionControl);
+
+        $this->routeItemSessionControl
+            ->method('getItemSessionControl')
+            ->willReturn($this->itemSessionControl);
+    }
+
+    /**
+     * @throws \common_exception_Error
+     * @throws \oat\taoQtiTest\models\runner\QtiRunnerEmptyResponsesException
+     * @throws \qtism\runtime\tests\AssessmentItemSessionException
+     */
+    public function testValidateAllowedToSkip()
+    {
+        $assessmentTestSession = $this->createMock(AssessmentTestSession::class);
+        $responses = $this->createMock(State::class);
+
+        $assessmentTestSession
+            ->method('getRoute')
+            ->willReturn($this->routeMock);
+
+        $this->itemSessionControl->expects($this->never())
+            ->method('mustValidateResponses');
+
+        $this->itemSessionControl->expects($this->once())
+            ->method('doesAllowSkipping')
+            ->willReturn(true);
+
+        $responses
+            ->method('containsNullOnly')
+            ->willReturn(true);
+
+        $this->subject->validate($assessmentTestSession, $responses);
+    }
+
+    public function testValidateNotAllowedToSkip(): void
+    {
+        $assessmentTestSession = $this->createMock(AssessmentTestSession::class);
+        $responses = $this->createMock(State::class);
+
+        $assessmentTestSession
+            ->method('getRoute')
+            ->willReturn($this->routeMock);
+
+        $this->itemSessionControl->expects($this->never())
+            ->method('mustValidateResponses');
+
+        $this->itemSessionControl->expects($this->exactly(2))
+            ->method('doesAllowSkipping')
+            ->willReturn(false);
+
+        $responses
+            ->method('containsNullOnly')
+            ->willReturn(true);
+
+        $this->expectException(QtiRunnerEmptyResponsesException::class);
+
+        $this->subject->validate($assessmentTestSession, $responses);
+    }
+
+    public function testValidateNotAllowedToSkipValidateResponses(): void
+    {
+        $assessmentTestSession = $this->createMock(AssessmentTestSession::class);
+        $responses = $this->createMock(State::class);
+        $assessmentItemSession = $this->createMock(AssessmentItemSession::class);
+
+        $assessmentTestSession
+            ->method('getRoute')
+            ->willReturn($this->routeMock);
+
+        $this->itemSessionControl->expects($this->once())
+            ->method('mustValidateResponses')
+            ->willReturn(true);
+
+        $this->itemSessionControl->expects($this->exactly(2))
+            ->method('doesAllowSkipping')
+            ->willReturn(false);
+
+        $responses
+            ->method('containsNullOnly')
+            ->willReturn(false);
+
+        $assessmentTestSession->expects($this->once())
+            ->method('getCurrentAssessmentItemSession')
+            ->willReturn($assessmentItemSession);
+
+        $assessmentItemSession->expects($this->once())
+            ->method('checkResponseValidityConstraints');
+
+        $this->subject->validate($assessmentTestSession, $responses);
+    }
+}