diff --git a/src/CollectionSchema.php b/src/CollectionSchema.php
index 84ee67f..f6340bc 100644
--- a/src/CollectionSchema.php
+++ b/src/CollectionSchema.php
@@ -7,16 +7,16 @@
 /**
  * @template I
  *
- * @phpstan-type CollectionSchemaData array<I>
+ * @type CollectionSchemaData array<I>
  *
- * @extends JsonSchema<CollectionSchemaData>
+ * @implements JsonSchemaInterface<CollectionSchemaData>
  */
 abstract class CollectionSchema implements JsonSchemaInterface
 {
     /**
-     * @param JsonSchema<I> $itemSchema
+     * @psalm-param JsonSchemaInterface<I> $itemSchema
      */
-    public function __construct(private JsonSchema $itemSchema)
+    public function __construct(private JsonSchemaInterface $itemSchema)
     {
     }
 
diff --git a/src/EnumSchema.php b/src/EnumSchema.php
index 67a5449..a310aff 100644
--- a/src/EnumSchema.php
+++ b/src/EnumSchema.php
@@ -6,7 +6,8 @@
 
 /**
  * @template E
- * @extends JsonSchema<E>
+ *
+ * @implements JsonSchemaInterface<E>
  */
 abstract class EnumSchema implements JsonSchemaInterface
 {
diff --git a/src/JsonSchema.php b/src/JsonSchema.php
index 550b7a1..e4361d5 100644
--- a/src/JsonSchema.php
+++ b/src/JsonSchema.php
@@ -4,6 +4,8 @@
 
 namespace Knp\JsonSchema;
 
+use Knp\JsonSchema\Validator\Errors;
+
 /**
  * @template T of mixed
  *
@@ -116,7 +118,7 @@ public function jsonSerialize(): array
      *
      * @return array<string, mixed>
      */
-    protected static function constant($value): array
+    public static function constant($value): array
     {
         return [
             'const' => $value,
@@ -126,7 +128,7 @@ protected static function constant($value): array
     /**
      * @return array<string, mixed>
      */
-    protected static function null(): array
+    public static function null(): array
     {
         return [
             'type' => 'null',
@@ -136,7 +138,7 @@ protected static function null(): array
     /**
      * @return array<string, mixed>
      */
-    protected static function text(): array
+    public static function text(): array
     {
         return [
             'type' => 'string',
@@ -147,7 +149,7 @@ protected static function text(): array
     /**
      * @return array<string, mixed>
      */
-    protected static function boolean(): array
+    public static function boolean(): array
     {
         return [
             'type' => 'boolean',
@@ -157,7 +159,7 @@ protected static function boolean(): array
     /**
      * @return array<string, mixed>
      */
-    protected static function string(?string $format = null): array
+    public static function string(?string $format = null): array
     {
         $result = [
             ...self::text(),
@@ -174,7 +176,7 @@ protected static function string(?string $format = null): array
     /**
      * @return array<string, mixed>
      */
-    protected static function integer(): array
+    public static function integer(): array
     {
         return [
             'type' => 'integer',
@@ -184,7 +186,7 @@ protected static function integer(): array
     /**
      * @return array<string, mixed>
      */
-    protected static function number(): array
+    public static function number(): array
     {
         return [
             'type' => 'number',
@@ -194,7 +196,7 @@ protected static function number(): array
     /**
      * @return array<string, mixed>
      */
-    protected static function date(): array
+    public static function date(): array
     {
         return [
             'type' => 'string',
@@ -205,7 +207,7 @@ protected static function date(): array
     /**
      * @return array<string, mixed>
      */
-    protected static function positiveInteger(): array
+    public static function positiveInteger(): array
     {
         return [
             ...self::integer(),
@@ -218,7 +220,7 @@ protected static function positiveInteger(): array
      *
      * @return array{oneOf: array<array<string, mixed>>}
      */
-    protected static function oneOf(...$schemas): array
+    public static function oneOf(...$schemas): array
     {
         return [
             'oneOf' => $schemas,
diff --git a/src/JsonSchemaInterface.php b/src/JsonSchemaInterface.php
index 87805de..039dc34 100644
--- a/src/JsonSchemaInterface.php
+++ b/src/JsonSchemaInterface.php
@@ -5,9 +5,10 @@
 namespace Knp\JsonSchema;
 
 use JsonSerializable;
+use Knp\JsonSchema\Validator\Errors;
 
 /**
- * @template T of mixed
+ * @template T
  */
 interface JsonSchemaInterface extends JsonSerializable
 {
diff --git a/src/ObjectSchema.php b/src/ObjectSchema.php
index d419391..979b76c 100644
--- a/src/ObjectSchema.php
+++ b/src/ObjectSchema.php
@@ -5,13 +5,14 @@
 namespace Knp\JsonSchema;
 
 /**
- * @template T of array<string, mixed>
- * @extends JsonSchema<T>
+ * @template T
+ *
+ * @implements JsonSchemaInterface<T>
  */
 abstract class ObjectSchema implements JsonSchemaInterface
 {
     /**
-     * @var array<string, JsonSchema<mixed>>
+     * @var array<string, JsonSchemaInterface<mixed>>
      */
     private array $properties = [];
 
@@ -44,11 +45,11 @@ protected function hasAdditionalProperties(): bool
     }
 
     /**
-     * @template S
+     * @psalm-template S
      *
-     * @param JsonSchema<S> $schema
+     * @psalm-param JsonSchemaInterface<S> $schema
      */
-    protected function addProperty(string $name, JsonSchema $schema, bool $required = true): void
+    protected function addProperty(string $name, JsonSchemaInterface $schema, bool $required = true): void
     {
         $this->properties[$name] = $schema;
 
diff --git a/src/Scalar/UuidSchema.php b/src/Scalar/UuidSchema.php
index 5aeceb0..27c02c8 100644
--- a/src/Scalar/UuidSchema.php
+++ b/src/Scalar/UuidSchema.php
@@ -5,11 +5,12 @@
 namespace Knp\JsonSchema\Scalar;
 
 use Knp\JsonSchema\JsonSchema;
+use Knp\JsonSchema\JsonSchemaInterface;
 
 /**
- * @extends JsonSchema<string>
+ * @implements JsonSchemaInterface<string>
  */
-final class UuidSchema extends JsonSchema
+final class UuidSchema implements JsonSchemaInterface
 {
     private const PATTERN = '^[0-9a-f]{8}(-[0-9a-f]{4}){3}-[0-9a-f]{12}$';
 
@@ -37,7 +38,7 @@ public function getDescription(): string
     public function getSchema(): array
     {
         return array_merge(
-            self::string(),
+            JsonSchema::string(),
             [
                 'pattern' => self::PATTERN,
                 'minLength' => 36,
@@ -45,4 +46,24 @@ public function getSchema(): array
             ]
         );
     }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function jsonSerialize(): array
+    {
+        $schema = $this->getSchema();
+
+        /**
+         * @var array<string, mixed>&array{title: string, description: string, examples: array<T>}
+         */
+        return array_merge(
+            $schema,
+            [
+                'title' => $this->getTitle(),
+                'description' => $this->getDescription(),
+                'examples' => [...$this->getExamples()],
+            ],
+        );
+    }
 }
diff --git a/src/Validator.php b/src/Validator.php
index 8d98156..6f364df 100644
--- a/src/Validator.php
+++ b/src/Validator.php
@@ -9,10 +9,10 @@
 interface Validator
 {
     /**
-     * @template T
+     * @template T of array<array-key, mixed>
      *
-     * @param T                                         $data
-     * @param class-string<JsonSchema<T>>|JsonSchema<T> $schema
+     * @param array<array-key, mixed> $data
+     * @param JsonSchemaInterface<T> $schema
      */
-    public function validate($data, $schema): ?Errors;
+    public function validate(array $data, JsonSchemaInterface $schema): ?Errors;
 }