diff --git a/src/Dto/Connector/DefaultProviderDto.php b/src/Dto/Connector/DefaultProviderDto.php
index a32a972..d807612 100644
--- a/src/Dto/Connector/DefaultProviderDto.php
+++ b/src/Dto/Connector/DefaultProviderDto.php
@@ -6,12 +6,15 @@ use Symfony\Component\Validator\Constraints as Assert;
 
 class DefaultProviderDto
 {
+    #[Assert\NotBlank]
     #[Assert\IsTrue]
     public bool $ownerLegalAge;
 
+    #[Assert\NotBlank]
     #[Assert\IsTrue]
     public bool $acceptConditions;
 
+    #[Assert\NotBlank]
     #[Assert\IsTrue]
     public bool $waiveRetractationPeriod;
 }
diff --git a/src/Dto/Connector/EppClientProviderDomainDto.php b/src/Dto/Connector/EppClientProviderDomainDto.php
index f9aad21..ec21673 100644
--- a/src/Dto/Connector/EppClientProviderDomainDto.php
+++ b/src/Dto/Connector/EppClientProviderDomainDto.php
@@ -19,5 +19,9 @@ final class EppClientProviderDomainDto
     public string $password;
 
     #[Assert\NotBlank]
+    #[Assert\All([
+        new Assert\NotBlank(),
+        new Assert\Type('string'),
+    ])]
     public array $contacts;
 }
diff --git a/src/Dto/Connector/EppClientProviderDto.php b/src/Dto/Connector/EppClientProviderDto.php
index 544e4df..726d51a 100644
--- a/src/Dto/Connector/EppClientProviderDto.php
+++ b/src/Dto/Connector/EppClientProviderDto.php
@@ -10,9 +10,11 @@ final class EppClientProviderDto extends DefaultProviderDto
     public string $version;
 
     #[Assert\NotBlank]
+    #[Assert\Language]
     public string $language;
 
     #[Assert\NotBlank]
+    #[Assert\Url(protocols: ['ssl', 'tls', 'http', 'https'], requireTld: true)]
     public string $hostname;
 
     #[Assert\NotBlank]
@@ -24,10 +26,22 @@ final class EppClientProviderDto extends DefaultProviderDto
     #[Assert\NotBlank]
     public EppClientProviderDomainDto $domain;
 
+    #[Assert\All([
+        new Assert\NotBlank(),
+        new Assert\Type('string'),
+    ])]
     public array $xPathURI = [];
 
+    #[Assert\All([
+        new Assert\NotBlank(),
+        new Assert\Type('string'),
+    ])]
     public array $extURI = [];
 
+    #[Assert\All([
+        new Assert\NotBlank(),
+        new Assert\Type('string'),
+    ])]
     public array $objURI = [];
 
     #[Assert\NotBlank]
diff --git a/src/Dto/Connector/OvhProviderDto.php b/src/Dto/Connector/OvhProviderDto.php
index 2bd0248..7af24f9 100644
--- a/src/Dto/Connector/OvhProviderDto.php
+++ b/src/Dto/Connector/OvhProviderDto.php
@@ -18,6 +18,7 @@ final class OvhProviderDto extends DefaultProviderDto
     #[Assert\NotBlank]
     public string $consumerKey;
 
+    #[Assert\NotBlank]
     #[Assert\Choice(['create-default', 'create-premium'])]
     public string $pricingMode;