diff --git a/src/CollectionSchema.php b/src/CollectionSchema.php
index d73279f..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 extends JsonSchema
+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)
     {
     }
 
@@ -30,6 +30,11 @@ public function getTitle(): string
         return sprintf('Collection<%s>', $this->itemSchema->getTitle());
     }
 
+    public function getDescription(): string
+    {
+        return sprintf('Collection of %s', $this->itemSchema->getDescription());
+    }
+
     protected function getUniqueItems(): ?bool
     {
         return null;
@@ -50,7 +55,7 @@ protected function getRange(): ?int
         return null;
     }
 
-    protected function getSchema(): array
+    public function getSchema(): array
     {
         $schema = [
             'type' => 'array',
@@ -71,4 +76,24 @@ protected function getSchema(): array
 
         return $schema;
     }
+
+    /**
+     * {@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/EnumSchema.php b/src/EnumSchema.php
index 2db3285..a310aff 100644
--- a/src/EnumSchema.php
+++ b/src/EnumSchema.php
@@ -6,16 +6,22 @@
 
 /**
  * @template E
- * @extends JsonSchema<E>
+ *
+ * @implements JsonSchemaInterface<E>
  */
-abstract class EnumSchema extends JsonSchema
+abstract class EnumSchema implements JsonSchemaInterface
 {
+    /**
+     * @return iterable<int, E>
+     */
+    abstract protected function getEnum(): iterable;
+
     public function getExamples(): iterable
     {
         return $this->getEnum();
     }
 
-    protected function getSchema(): array
+    public function getSchema(): array
     {
         return [
             'enum' => [...$this->getEnum()],
@@ -23,7 +29,22 @@ protected function getSchema(): array
     }
 
     /**
-     * @return iterable<int, E>
+     * {@inheritdoc}
      */
-    abstract protected function getEnum(): iterable;
+    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/JsonSchema.php b/src/JsonSchema.php
index 0227619..e4361d5 100644
--- a/src/JsonSchema.php
+++ b/src/JsonSchema.php
@@ -4,22 +4,54 @@
 
 namespace Knp\JsonSchema;
 
+use Knp\JsonSchema\Validator\Errors;
+
 /**
  * @template T of mixed
+ *
+ * @implements JsonSchemaInterface<T>
  */
-abstract class JsonSchema implements JsonSchemaInterface
+class JsonSchema implements JsonSchemaInterface
 {
+    private function __construct(
+        protected readonly string $title,
+        protected readonly string $description,
+        protected readonly iterable $examples,
+        protected readonly array $schema
+    ) {
+    }
+
+    public function getTitle(): string
+    {
+        return $this->title;
+    }
+
+    public function getDescription(): string
+    {
+        return $this->description;
+    }
+
+    public function getExamples(): iterable
+    {
+        yield from $this->examples;
+    }
+
+    public function getSchema(): array
+    {
+        return $this->schema;
+    }
+
     /**
-     * @param JsonSchema<E> $schema
      * @template E of mixed
+     * @param JsonSchemaInterface<E> $schema
      *
      * @return JsonSchema<null|E>
      */
-    public static function nullable(self $schema): self
+    public static function nullable(JsonSchemaInterface $schema): self
     {
         return self::create(
-            '',
-            '',
+            sprintf('Nullable<%s>', $schema->getTitle()),
+            $schema->getDescription(),
             [...$schema->getExamples(), null],
             ['oneOf' => [self::null(), $schema->jsonSerialize()]],
         );
@@ -36,64 +68,23 @@ public static function create(
         string $title,
         string $description,
         iterable $examples,
-        $schema
+        array $schema
     ): self {
-        return new class($title, $description, $examples, $schema) extends JsonSchema {
-            /**
-             * @var iterable<int, E>
-             */
-            private iterable $examples;
-
-            /**
-             * @param iterable<int, E>     $examples
-             * @param array<string, mixed> $schema
-             */
-            public function __construct(
-                private string $title,
-                private string $description,
-                iterable $examples,
-                private $schema
-            ) {
-                $this->examples = [...$examples];
-            }
-
-            public function getTitle(): string
-            {
-                return $this->title;
-            }
-
-            public function getDescription(): string
-            {
-                return $this->description;
-            }
-
-            /**
-             * @return iterable<int, E>
-             */
-            public function getExamples(): iterable
-            {
-                yield from $this->examples;
-            }
-
-            public function getSchema(): array
-            {
-                return $this->schema;
-            }
-        };
+        return new self($title, $description, $examples, $schema);
     }
 
     /**
      * @template I
      *
-     * @param JsonSchema<I> $jsonSchema
+     * @param JsonSchemaInterface<I> $jsonSchema
      *
      * @return JsonSchema<array<int, I>>
      */
-    public static function collection(self $jsonSchema): self
+    public static function collection(JsonSchemaInterface $jsonSchema): self
     {
         return self::create(
             sprintf('Collection<%s>', $jsonSchema->getTitle()),
-            '',
+            $jsonSchema->getDescription(),
             [[...$jsonSchema->getExamples()]],
             [
                 'type' => 'array',
@@ -103,9 +94,9 @@ public static function collection(self $jsonSchema): self
     }
 
     /**
-     * @return array<string, mixed>&array{title: string, description: string, examples: array<T>}
+     * {@inheritdoc}
      */
-    public function jsonSerialize(): mixed
+    public function jsonSerialize(): array
     {
         $schema = $this->getSchema();
 
@@ -122,27 +113,12 @@ public function jsonSerialize(): mixed
         );
     }
 
-    /**
-     * @return iterable<int, T>
-     */
-    abstract public function getExamples(): iterable;
-
-    public function getTitle(): string
-    {
-        return '';
-    }
-
-    public function getDescription(): string
-    {
-        return '';
-    }
-
     /**
      * @param scalar $value
      *
      * @return array<string, mixed>
      */
-    protected static function constant($value): array
+    public static function constant($value): array
     {
         return [
             'const' => $value,
@@ -152,7 +128,7 @@ protected static function constant($value): array
     /**
      * @return array<string, mixed>
      */
-    protected static function null(): array
+    public static function null(): array
     {
         return [
             'type' => 'null',
@@ -162,7 +138,7 @@ protected static function null(): array
     /**
      * @return array<string, mixed>
      */
-    protected static function text(): array
+    public static function text(): array
     {
         return [
             'type' => 'string',
@@ -173,7 +149,7 @@ protected static function text(): array
     /**
      * @return array<string, mixed>
      */
-    protected static function boolean(): array
+    public static function boolean(): array
     {
         return [
             'type' => 'boolean',
@@ -183,7 +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(),
@@ -200,7 +176,7 @@ protected static function string(?string $format = null): array
     /**
      * @return array<string, mixed>
      */
-    protected static function integer(): array
+    public static function integer(): array
     {
         return [
             'type' => 'integer',
@@ -210,7 +186,7 @@ protected static function integer(): array
     /**
      * @return array<string, mixed>
      */
-    protected static function number(): array
+    public static function number(): array
     {
         return [
             'type' => 'number',
@@ -220,7 +196,7 @@ protected static function number(): array
     /**
      * @return array<string, mixed>
      */
-    protected static function date(): array
+    public static function date(): array
     {
         return [
             'type' => 'string',
@@ -231,7 +207,7 @@ protected static function date(): array
     /**
      * @return array<string, mixed>
      */
-    protected static function positiveInteger(): array
+    public static function positiveInteger(): array
     {
         return [
             ...self::integer(),
@@ -244,15 +220,10 @@ protected static function positiveInteger(): array
      *
      * @return array{oneOf: array<array<string, mixed>>}
      */
-    protected static function oneOf(...$schemas): array
+    public static function oneOf(...$schemas): array
     {
         return [
             'oneOf' => $schemas,
         ];
     }
-
-    /**
-     * @return array<string, mixed>
-     */
-    abstract protected function getSchema(): array;
 }
diff --git a/src/JsonSchemaInterface.php b/src/JsonSchemaInterface.php
index d99c044..039dc34 100644
--- a/src/JsonSchemaInterface.php
+++ b/src/JsonSchemaInterface.php
@@ -5,7 +5,29 @@
 namespace Knp\JsonSchema;
 
 use JsonSerializable;
+use Knp\JsonSchema\Validator\Errors;
 
+/**
+ * @template T
+ */
 interface JsonSchemaInterface extends JsonSerializable
 {
+    /**
+     * @return array<string, mixed>&array{title: string, description: string, examples: array<T>}
+     */
+    public function jsonSerialize(): array;
+
+    public function getTitle(): string;
+
+    public function getDescription(): string;
+
+    /**
+     * @return iterable<int, T>
+     */
+    public function getExamples(): iterable;
+
+    /**
+     * @return array<string, mixed>
+     */
+    public function getSchema(): array;
 }
diff --git a/src/ObjectSchema.php b/src/ObjectSchema.php
index 1d8849e..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 extends JsonSchema
+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;
 
@@ -59,7 +60,7 @@ protected function addProperty(string $name, JsonSchema $schema, bool $required
         }
     }
 
-    protected function getSchema(): array
+    public function getSchema(): array
     {
         return [
             'type' => 'object',
@@ -68,4 +69,24 @@ protected function getSchema(): array
             'required' => $this->required,
         ];
     }
+
+    /**
+     * {@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/Scalar/UuidSchema.php b/src/Scalar/UuidSchema.php
index b51e083..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}$';
 
@@ -34,10 +35,10 @@ public function getDescription(): string
     /**
      * {@inheritDoc}
      */
-    protected function getSchema(): array
+    public function getSchema(): array
     {
         return array_merge(
-            self::string(),
+            JsonSchema::string(),
             [
                 'pattern' => self::PATTERN,
                 'minLength' => 36,
@@ -45,4 +46,24 @@ protected 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;
 }