diff --git a/src/Rfc4122/Validator.php b/src/Rfc4122/Validator.php
index 97cdb7e..7dcf078 100644
--- a/src/Rfc4122/Validator.php
+++ b/src/Rfc4122/Validator.php
@@ -22,6 +22,8 @@ use function str_replace;
 
 /**
  * Rfc4122\Validator validates strings as UUIDs of the RFC 4122 variant
+ *
+ * @psalm-immutable
  */
 final class Validator implements ValidatorInterface
 {
@@ -29,7 +31,6 @@ final class Validator implements ValidatorInterface
         . '[1-5]{1}[0-9A-Fa-f]{3}-[ABab89]{1}[0-9A-Fa-f]{3}-[0-9A-Fa-f]{12}$';
 
     /**
-     * @psalm-pure
      * @psalm-return non-empty-string
      * @psalm-suppress MoreSpecificReturnType we know that the retrieved `string` is never empty
      * @psalm-suppress LessSpecificReturnStatement we know that the retrieved `string` is never empty
@@ -39,9 +40,6 @@ final class Validator implements ValidatorInterface
         return self::VALID_PATTERN;
     }
 
-    /**
-     * @psalm-pure
-     */
     public function validate(string $uuid): bool
     {
         $uuid = str_replace(['urn:', 'uuid:', 'URN:', 'UUID:', '{', '}'], '', $uuid);
diff --git a/src/Validator/GenericValidator.php b/src/Validator/GenericValidator.php
index 84fc645..f6a6010 100644
--- a/src/Validator/GenericValidator.php
+++ b/src/Validator/GenericValidator.php
@@ -21,6 +21,8 @@ use function str_replace;
 
 /**
  * GenericValidator validates strings as UUIDs of any variant
+ *
+ * @psalm-immutable
  */
 final class GenericValidator implements ValidatorInterface
 {
@@ -30,7 +32,6 @@ final class GenericValidator implements ValidatorInterface
     private const VALID_PATTERN = '^[0-9A-Fa-f]{8}-[0-9A-Fa-f]{4}-[0-9A-Fa-f]{4}-[0-9A-Fa-f]{4}-[0-9A-Fa-f]{12}$';
 
     /**
-     * @psalm-pure
      * @psalm-return non-empty-string
      * @psalm-suppress MoreSpecificReturnType we know that the retrieved `string` is never empty
      * @psalm-suppress LessSpecificReturnStatement we know that the retrieved `string` is never empty
@@ -40,9 +41,6 @@ final class GenericValidator implements ValidatorInterface
         return self::VALID_PATTERN;
     }
 
-    /**
-     * @psalm-pure
-     */
     public function validate(string $uuid): bool
     {
         $uuid = str_replace(['urn:', 'uuid:', 'URN:', 'UUID:', '{', '}'], '', $uuid);
diff --git a/src/Validator/ValidatorInterface.php b/src/Validator/ValidatorInterface.php
index ef813c2..3d4bd6f 100644
--- a/src/Validator/ValidatorInterface.php
+++ b/src/Validator/ValidatorInterface.php
@@ -16,6 +16,8 @@ namespace Ramsey\Uuid\Validator;
 
 /**
  * A validator validates a string as a proper UUID
+ *
+ * @psalm-immutable
  */
 interface ValidatorInterface
 {
@@ -24,7 +26,6 @@ interface ValidatorInterface
      *
      * @return string The regular expression pattern this validator uses
      *
-     * @psalm-pure
      * @psalm-return non-empty-string
      */
     public function getPattern(): string;
@@ -35,8 +36,6 @@ interface ValidatorInterface
      * @param string $uuid The string to validate as a UUID
      *
      * @return bool True if the string is a valid UUID, false otherwise
-     *
-     * @psalm-pure
      */
     public function validate(string $uuid): bool;
 }