Add some more tests and docs

src/mcp-sdk/src/Server/JsonRpcHandler.php

@@ -12,14 +12,14 @@
 namespace Symfony\AI\McpSdk\Server;
 
 use Psr\Log\LoggerInterface;
+use Symfony\AI\McpSdk\Exception\ExceptionInterface;
 use Symfony\AI\McpSdk\Exception\HandlerNotFoundException;
 use Symfony\AI\McpSdk\Exception\NotFoundExceptionInterface;
 use Symfony\AI\McpSdk\Message\Error;
 use Symfony\AI\McpSdk\Message\Factory;
 use Symfony\AI\McpSdk\Message\Notification;
 use Symfony\AI\McpSdk\Message\Request;
 use Symfony\AI\McpSdk\Message\Response;
-use Symfony\Component\String\Exception\ExceptionInterface;
 
 /**
  * @final
@@ -51,6 +51,7 @@ public function __construct(
     }
 
     /**
+     * @throws ExceptionInterface
      * @throws \JsonException
      */
     public function process(string $message): ?string
@@ -88,6 +89,9 @@ public function process(string $message): ?string
         }
     }
 
+    /**
+     * @throws \JsonException
+     */
     private function encodeResponse(Response|Error|null $response): ?string
     {
         if (null === $response) {
@@ -105,15 +109,22 @@ private function encodeResponse(Response|Error|null $response): ?string
         return json_encode($response, \JSON_THROW_ON_ERROR);
     }
 
+    /**
+     * @throws ExceptionInterface
+     */
     private function handleNotification(Notification $notification): null
     {
+        $handled = false;
         foreach ($this->notificationHandlers as $handler) {
             if ($handler->supports($notification)) {
-                return $handler->handle($notification);
+                $handler->handle($notification);
+                $handled = true;
             }
         }
 
-        $this->logger->warning(\sprintf('No handler found for "%s".', $notification->method), ['notification' => $notification]);
+        if (!$handled) {
+            $this->logger->warning(\sprintf('No handler found for "%s".', $notification->method), ['notification' => $notification]);
+        }
 
         return null;
     }

src/mcp-sdk/src/Server/NotificationHandler/InitializedHandler.php

@@ -20,8 +20,7 @@ protected function supportedNotification(): string
         return 'initialized';
     }
 
-    public function handle(Notification $notification): null
+    public function handle(Notification $notification): void
     {
-        return null;
     }
 }

src/mcp-sdk/src/Server/NotificationHandlerInterface.php

@@ -11,11 +11,15 @@
 
 namespace Symfony\AI\McpSdk\Server;
 
+use Symfony\AI\McpSdk\Exception\ExceptionInterface;
 use Symfony\AI\McpSdk\Message\Notification;
 
 interface NotificationHandlerInterface
 {
     public function supports(Notification $message): bool;
 
-    public function handle(Notification $notification): null;
+    /**
+     * @throws ExceptionInterface
+     */
+    public function handle(Notification $notification): void;
 }

src/mcp-sdk/src/Server/RequestHandlerInterface.php

@@ -11,6 +11,7 @@
 
 namespace Symfony\AI\McpSdk\Server;
 
+use Symfony\AI\McpSdk\Exception\ExceptionInterface;
 use Symfony\AI\McpSdk\Message\Error;
 use Symfony\AI\McpSdk\Message\Request;
 use Symfony\AI\McpSdk\Message\Response;
@@ -19,5 +20,8 @@ interface RequestHandlerInterface
 {
     public function supports(Request $message): bool;
 
+    /**
+     * @throws ExceptionInterface
+     */
     public function createResponse(Request $message): Response|Error;
 }

src/mcp-sdk/tests/Message/ErrorTest.php

@@ -11,9 +11,13 @@
 
 namespace Symfony\AI\McpSdk\Tests\Message;
 
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\Attributes\Small;
 use PHPUnit\Framework\TestCase;
 use Symfony\AI\McpSdk\Message\Error;
 
+#[Small]
+#[CoversClass(Error::class)]
 final class ErrorTest extends TestCase
 {
     public function testWithIntegerId(): void

src/mcp-sdk/tests/Message/FactoryTest.php

@@ -11,11 +11,15 @@
 
 namespace Symfony\AI\McpSdk\Tests\Message;
 
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\Attributes\Small;
 use PHPUnit\Framework\TestCase;
 use Symfony\AI\McpSdk\Message\Factory;
 use Symfony\AI\McpSdk\Message\Notification;
 use Symfony\AI\McpSdk\Message\Request;
 
+#[Small]
+#[CoversClass(Factory::class)]
 final class FactoryTest extends TestCase
 {
     private Factory $factory;

src/mcp-sdk/tests/Message/ResponseTest.php

@@ -11,9 +11,13 @@
 
 namespace Symfony\AI\McpSdk\Tests\Message;
 
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\Attributes\Small;
 use PHPUnit\Framework\TestCase;
 use Symfony\AI\McpSdk\Message\Response;
 
+#[Small]
+#[CoversClass(Response::class)]
 final class ResponseTest extends TestCase
 {
     public function testWithIntegerId(): void

src/mcp-sdk/tests/Server/JsonRpcHandlerTest.php

@@ -0,0 +1,88 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\AI\McpSdk\Tests\Server;
+
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\Attributes\Small;
+use PHPUnit\Framework\Attributes\TestDox;
+use PHPUnit\Framework\TestCase;
+use Psr\Log\NullLogger;
+use Symfony\AI\McpSdk\Message\Factory;
+use Symfony\AI\McpSdk\Message\Response;
+use Symfony\AI\McpSdk\Server\JsonRpcHandler;
+use Symfony\AI\McpSdk\Server\NotificationHandlerInterface;
+use Symfony\AI\McpSdk\Server\RequestHandlerInterface;
+
+#[Small]
+#[CoversClass(JsonRpcHandler::class)]
+class JsonRpcHandlerTest extends TestCase
+{
+    #[TestDox('Make sure a single notification can be handled by multiple handlers.')]
+    public function testHandleMultipleNotifications(): void
+    {
+        $handlerA = $this->getMockBuilder(NotificationHandlerInterface::class)
+            ->disableOriginalConstructor()
+            ->onlyMethods(['supports', 'handle'])
+            ->getMock();
+        $handlerA->method('supports')->willReturn(true);
+        $handlerA->expects($this->once())->method('handle');
+
+        $handlerB = $this->getMockBuilder(NotificationHandlerInterface::class)
+            ->disableOriginalConstructor()
+            ->onlyMethods(['supports', 'handle'])
+            ->getMock();
+        $handlerB->method('supports')->willReturn(false);
+        $handlerB->expects($this->never())->method('handle');
+
+        $handlerC = $this->getMockBuilder(NotificationHandlerInterface::class)
+            ->disableOriginalConstructor()
+            ->onlyMethods(['supports', 'handle'])
+            ->getMock();
+        $handlerC->method('supports')->willReturn(true);
+        $handlerC->expects($this->once())->method('handle');
+
+        $jsonRpc = new JsonRpcHandler(new Factory(), [], [$handlerA, $handlerB, $handlerC], new NullLogger());
+        $jsonRpc->process(
+            '{"jsonrpc": "2.0", "id": 1, "method": "notifications/foobar"}'
+        );
+    }
+
+    #[TestDox('Make sure a single request can NOT be handled by multiple handlers.')]
+    public function testHandleMultipleRequests(): void
+    {
+        $handlerA = $this->getMockBuilder(RequestHandlerInterface::class)
+            ->disableOriginalConstructor()
+            ->onlyMethods(['supports', 'createResponse'])
+            ->getMock();
+        $handlerA->method('supports')->willReturn(true);
+        $handlerA->expects($this->once())->method('createResponse')->willReturn(new Response(1));
+
+        $handlerB = $this->getMockBuilder(RequestHandlerInterface::class)
+            ->disableOriginalConstructor()
+            ->onlyMethods(['supports', 'createResponse'])
+            ->getMock();
+        $handlerB->method('supports')->willReturn(false);
+        $handlerB->expects($this->never())->method('createResponse');
+
+        $handlerC = $this->getMockBuilder(RequestHandlerInterface::class)
+            ->disableOriginalConstructor()
+            ->onlyMethods(['supports', 'createResponse'])
+            ->getMock();
+        $handlerC->method('supports')->willReturn(true);
+        $handlerC->expects($this->never())->method('createResponse');
+
+        $jsonRpc = new JsonRpcHandler(new Factory(), [$handlerA, $handlerB, $handlerC], [], new NullLogger());
+        $jsonRpc->process(
+            '{"jsonrpc": "2.0", "id": 1, "method": "request/foobar"}'
+        );
+    }
+}

src/mcp-sdk/tests/Server/RequestHandler/ToolListHandlerTest.php

@@ -0,0 +1,106 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\AI\McpSdk\Tests\Server\RequestHandler;
+
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\Attributes\Small;
+use PHPUnit\Framework\TestCase;
+use Symfony\AI\McpSdk\Capability\Tool\CollectionInterface;
+use Symfony\AI\McpSdk\Capability\Tool\MetadataInterface;
+use Symfony\AI\McpSdk\Message\Request;
+use Symfony\AI\McpSdk\Server\RequestHandler\ToolListHandler;
+
+#[Small]
+#[CoversClass(ToolListHandler::class)]
+class ToolListHandlerTest extends TestCase
+{
+    public function testHandleEmpty(): void
+    {
+        $collection = $this->getMockBuilder(CollectionInterface::class)
+            ->disableOriginalConstructor()
+            ->onlyMethods(['getMetadata'])
+            ->getMock();
+        $collection->expects($this->once())->method('getMetadata')->willReturn([]);
+
+        $handler = new ToolListHandler($collection);
+        $message = new Request(1, 'tools/list', []);
+        $response = $handler->createResponse($message);
+        $this->assertEquals(1, $response->id);
+        $this->assertEquals(['tools' => []], $response->result);
+    }
+
+    public function testHandleReturnAll(): void
+    {
+        $item = new class implements MetadataInterface {
+            public function getName(): string
+            {
+                return 'test_tool';
+            }
+
+            public function getDescription(): string
+            {
+                return 'A test tool';
+            }
+
+            public function getInputSchema(): array
+            {
+                return [
+                    'type' => 'object',
+                ];
+            }
+        };
+        $collection = $this->getMockBuilder(CollectionInterface::class)
+            ->disableOriginalConstructor()
+            ->onlyMethods(['getMetadata'])
+            ->getMock();
+        $collection->expects($this->once())->method('getMetadata')->willReturn([$item]);
+
+        $handler = new ToolListHandler($collection);
+        $message = new Request(1, 'tools/list', []);
+        $response = $handler->createResponse($message);
+        $this->assertCount(1, $response->result['tools']);
+        $this->assertArrayNotHasKey('nextCursor', $response->result);
+    }
+
+    public function testHandlePagination(): void
+    {
+        $item = new class implements MetadataInterface {
+            public function getName(): string
+            {
+                return 'test_tool';
+            }
+
+            public function getDescription(): string
+            {
+                return 'A test tool';
+            }
+
+            public function getInputSchema(): array
+            {
+                return [
+                    'type' => 'object',
+                ];
+            }
+        };
+        $collection = $this->getMockBuilder(CollectionInterface::class)
+            ->disableOriginalConstructor()
+            ->onlyMethods(['getMetadata'])
+            ->getMock();
+        $collection->expects($this->once())->method('getMetadata')->willReturn([$item, $item]);
+
+        $handler = new ToolListHandler($collection, 2);
+        $message = new Request(1, 'tools/list', []);
+        $response = $handler->createResponse($message);
+        $this->assertCount(2, $response->result['tools']);
+        $this->assertArrayHasKey('nextCursor', $response->result);
+    }
+}

src/mcp-sdk/tests/ServerTest.php

@@ -11,13 +11,17 @@
 
 namespace Symfony\AI\McpSdk\Tests;
 
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\Attributes\Small;
 use PHPUnit\Framework\MockObject\Stub\Exception;
 use PHPUnit\Framework\TestCase;
 use Psr\Log\NullLogger;
 use Symfony\AI\McpSdk\Server;
 use Symfony\AI\McpSdk\Server\JsonRpcHandler;
 use Symfony\AI\McpSdk\Tests\Fixtures\InMemoryTransport;
 
+#[Small]
+#[CoversClass(Server::class)]
 class ServerTest extends TestCase
 {
     public function testJsonExceptions(): void