diff --git a/module/Core/src/RedirectRule/Model/Validation/RedirectRulesInputFilter.php b/module/Core/src/RedirectRule/Model/Validation/RedirectRulesInputFilter.php
index 42b83c76..5decaf4c 100644
--- a/module/Core/src/RedirectRule/Model/Validation/RedirectRulesInputFilter.php
+++ b/module/Core/src/RedirectRule/Model/Validation/RedirectRulesInputFilter.php
@@ -48,7 +48,7 @@ class RedirectRulesInputFilter extends InputFilter
         $redirectRuleInputFilter = new InputFilter();
 
         $longUrl = InputFactory::basic(self::RULE_LONG_URL, required: true);
-        $longUrl->setValidatorChain(ShortUrlInputFilter::longUrlValidators());
+        $longUrl->getValidatorChain()->merge(ShortUrlInputFilter::longUrlValidators());
         $redirectRuleInputFilter->add($longUrl);
 
         $conditionsInputFilter = new CollectionInputFilter();
diff --git a/module/Rest/test/Action/RedirectRule/SetRedirectRulesActionTest.php b/module/Rest/test/Action/RedirectRule/SetRedirectRulesActionTest.php
new file mode 100644
index 00000000..e330839c
--- /dev/null
+++ b/module/Rest/test/Action/RedirectRule/SetRedirectRulesActionTest.php
@@ -0,0 +1,58 @@
+<?php
+
+declare(strict_types=1);
+
+namespace ShlinkioTest\Shlink\Rest\Action\RedirectRule;
+
+use Doctrine\Common\Collections\ArrayCollection;
+use Laminas\Diactoros\Response\JsonResponse;
+use Laminas\Diactoros\ServerRequestFactory;
+use PHPUnit\Framework\Attributes\Test;
+use PHPUnit\Framework\MockObject\MockObject;
+use PHPUnit\Framework\TestCase;
+use Shlinkio\Shlink\Core\Model\DeviceType;
+use Shlinkio\Shlink\Core\RedirectRule\Entity\RedirectCondition;
+use Shlinkio\Shlink\Core\RedirectRule\Entity\ShortUrlRedirectRule;
+use Shlinkio\Shlink\Core\RedirectRule\ShortUrlRedirectRuleServiceInterface;
+use Shlinkio\Shlink\Core\ShortUrl\Entity\ShortUrl;
+use Shlinkio\Shlink\Core\ShortUrl\ShortUrlResolverInterface;
+use Shlinkio\Shlink\Rest\Action\RedirectRule\SetRedirectRulesAction;
+use Shlinkio\Shlink\Rest\Entity\ApiKey;
+
+class SetRedirectRulesActionTest extends TestCase
+{
+    private ShortUrlResolverInterface & MockObject $urlResolver;
+    private ShortUrlRedirectRuleServiceInterface & MockObject $ruleService;
+    private SetRedirectRulesAction $action;
+
+    protected function setUp(): void
+    {
+        $this->urlResolver = $this->createMock(ShortUrlResolverInterface::class);
+        $this->ruleService = $this->createMock(ShortUrlRedirectRuleServiceInterface::class);
+
+        $this->action = new SetRedirectRulesAction($this->urlResolver, $this->ruleService);
+    }
+
+    #[Test]
+    public function requestIsHandledAndRulesAreReturned(): void
+    {
+        $shortUrl = ShortUrl::withLongUrl('https://example.com');
+        $request = ServerRequestFactory::fromGlobals()->withAttribute(ApiKey::class, ApiKey::create());
+        $conditions = [RedirectCondition::forDevice(DeviceType::ANDROID), RedirectCondition::forLanguage('en-US')];
+        $redirectRules = [
+            new ShortUrlRedirectRule($shortUrl, 1, 'https://example.com/rule', new ArrayCollection($conditions)),
+        ];
+
+        $this->urlResolver->expects($this->once())->method('resolveShortUrl')->willReturn($shortUrl);
+        $this->ruleService->expects($this->once())->method('setRulesForShortUrl')->willReturn($redirectRules);
+
+        /** @var JsonResponse $response */
+        $response = $this->action->handle($request);
+        $payload = $response->getPayload();
+
+        self::assertEquals([
+            'defaultLongUrl' => $shortUrl->getLongUrl(),
+            'redirectRules' => $redirectRules,
+        ], $payload);
+    }
+}