feat: add support of collection to MCP

src/Mcp/Capability/Registry/Loader.php

@@ -47,17 +47,22 @@ public function load(RegistryInterface $registry): void
                 foreach ($resource->getMcp() ?? [] as $mcp) {
                     if ($mcp instanceof McpTool) {
                         $inputClass = $mcp->getInput()['class'] ?? $mcp->getClass();
-                        $schema = $this->schemaFactory->buildSchema($inputClass, 'json', Schema::TYPE_INPUT, $mcp, null, [SchemaFactory::FORCE_SUBSCHEMA => true]);
-                        $outputSchema = $this->schemaFactory->buildSchema($inputClass, 'json', Schema::TYPE_OUTPUT, $mcp, null, [SchemaFactory::FORCE_SUBSCHEMA => true]);
+                        $inputFormat = array_first($mcp->getInputFormats() ?? ['json']);
+                        $inputSchema = $this->schemaFactory->buildSchema($inputClass, $inputFormat, Schema::TYPE_INPUT, $mcp, null, [SchemaFactory::FORCE_SUBSCHEMA => true]);
+
+                        $outputClass = $mcp->getOutput()['class'] ?? $mcp->getClass();
+                        $outputFormat = array_first($mcp->getOutputFormats() ?? ['jsonld']);
+                        $outputSchema = $this->schemaFactory->buildSchema($outputClass, $outputFormat, Schema::TYPE_OUTPUT, $mcp, null, [SchemaFactory::FORCE_SUBSCHEMA => true]);
+
                         $registry->registerTool(
                             new Tool(
                                 name: $mcp->getName(),
-                                inputSchema: $schema->getDefinitions()[$schema->getRootDefinitionKey()]->getArrayCopy(),
+                                inputSchema: $inputSchema->getDefinitions()[$inputSchema->getRootDefinitionKey()]->getArrayCopy(),
                                 description: $mcp->getDescription(),
                                 annotations: $mcp->getAnnotations() ? ToolAnnotations::fromArray($mcp->getAnnotations()) : null,
                                 icons: $mcp->getIcons(),
                                 meta: $mcp->getMeta(),
-                                outputSchema: $outputSchema->getDefinitions()[$outputSchema->getRootDefinitionKey()]->getArrayCopy(),
+                                outputSchema: $outputSchema->getArrayCopy(),
                             ),
                             self::HANDLER,
                             true,

src/Mcp/State/StructuredContentProcessor.php

@@ -63,7 +63,7 @@ public function process(mixed $data, Operation $operation, array $uriVariables =
                 'operation' => $operation,
             ]);
             $serializerContext['uri_variables'] = $uriVariables;
-            $format = $request->getRequestFormat('') ?: 'json';
+            $format = $request->getRequestFormat('') ?: 'jsonld';
             $structuredContent = $this->serializer->normalize($result, $format, $serializerContext);
             $result = $this->serializer->encode($structuredContent, $format, $serializerContext);
         }

src/Mcp/composer.json

@@ -30,7 +30,8 @@
         "php": ">=8.2",
         "api-platform/metadata": "^4.2",
         "api-platform/json-schema": "^4.2",
-        "mcp/sdk": "^0.3.0"
+        "mcp/sdk": "^0.3.0",
+        "symfony/polyfill-php85": "^1.32"
     },
     "autoload": {
         "psr-4": {

src/Metadata/McpTool.php

@@ -20,7 +20,7 @@
 use Symfony\Component\WebLink\Link as WebLink;
 
 #[\Attribute(\Attribute::TARGET_CLASS | \Attribute::TARGET_METHOD | \Attribute::IS_REPEATABLE)]
-final class McpTool extends HttpOperation
+class McpTool extends HttpOperation
 {
     /**
      * @param string|null                                    $name              The name of the tool (defaults to the method name)

src/Metadata/McpToolCollection.php

@@ -0,0 +1,19 @@
+<?php
+
+/*
+ * This file is part of the API Platform project.
+ *
+ * (c) Kévin Dunglas <dunglas@gmail.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+declare(strict_types=1);
+
+namespace ApiPlatform\Metadata;
+
+#[\Attribute(\Attribute::TARGET_CLASS | \Attribute::TARGET_METHOD | \Attribute::IS_REPEATABLE)]
+final class McpToolCollection extends McpTool implements CollectionOperationInterface
+{
+}

src/Metadata/Resource/Factory/InputOutputResourceMetadataCollectionFactory.php

@@ -48,6 +48,10 @@ public function create(string $resourceClass): ResourceMetadataCollection
                 $resourceMetadata = $resourceMetadata->withGraphQlOperations($this->getTransformedOperations($resourceMetadata->getGraphQlOperations(), $resourceMetadata));
             }
 
+            if ($resourceMetadata->getMcp()) {
+                $resourceMetadata = $resourceMetadata->withMcp($this->getTransformedOperations($resourceMetadata->getMcp(), $resourceMetadata));
+            }
+
             $resourceMetadataCollection[$key] = $resourceMetadata;
         }
 

tests/Fixtures/TestBundle/Dto/SearchDto.php

@@ -0,0 +1,19 @@
+<?php
+
+/*
+ * This file is part of the API Platform project.
+ *
+ * (c) Kévin Dunglas <dunglas@gmail.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+declare(strict_types=1);
+
+namespace ApiPlatform\Tests\Fixtures\TestBundle\Dto;
+
+final class SearchDto
+{
+    public string $search;
+}

tests/Fixtures/TestBundle/Entity/McpBook.php

@@ -15,6 +15,9 @@
 
 use ApiPlatform\Metadata\ApiResource;
 use ApiPlatform\Metadata\McpTool;
+use ApiPlatform\Metadata\McpToolCollection;
+use ApiPlatform\Tests\Fixtures\TestBundle\Dto\SearchDto;
+use ApiPlatform\Tests\Fixtures\TestBundle\State\McpBookListProcessor;
 use Doctrine\ORM\Mapping as ORM;
 
 #[ApiResource(
@@ -27,6 +30,12 @@
         'update_book_status' => new McpTool(
             processor: [self::class, 'process']
         ),
+        'list_books' => new McpToolCollection(
+            description: 'List Books',
+            input: SearchDto::class,
+            processor: McpBookListProcessor::class,
+            structuredContent: true,
+        ),
     ]
 )]
 #[ORM\Entity]

tests/Fixtures/TestBundle/State/McpBookListProcessor.php

@@ -0,0 +1,31 @@
+<?php
+
+/*
+ * This file is part of the API Platform project.
+ *
+ * (c) Kévin Dunglas <dunglas@gmail.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+declare(strict_types=1);
+
+namespace ApiPlatform\Tests\Fixtures\TestBundle\State;
+
+use ApiPlatform\Metadata\Operation;
+use ApiPlatform\State\ProcessorInterface;
+use ApiPlatform\Tests\Fixtures\TestBundle\Entity\McpBook;
+use Doctrine\Persistence\ManagerRegistry;
+
+class McpBookListProcessor implements ProcessorInterface
+{
+    public function __construct(private readonly ManagerRegistry $managerRegistry)
+    {
+    }
+
+    public function process(mixed $data, Operation $operation, array $uriVariables = [], array $context = []): ?iterable
+    {
+        return $this->managerRegistry->getRepository(McpBook::class)->findAll();
+    }
+}

tests/Fixtures/app/config/config_common.yml

@@ -142,6 +142,11 @@ services:
         tags:
             - name: 'api_platform.state_processor'
 
+    ApiPlatform\Tests\Fixtures\TestBundle\State\McpBookListProcessor:
+        class: 'ApiPlatform\Tests\Fixtures\TestBundle\State\McpBookListProcessor'
+        arguments: [ '@doctrine' ]
+        tags:
+            - name: 'api_platform.state_processor'
 
     ApiPlatform\Tests\Fixtures\TestBundle\State\ContainNonResourceProvider:
         class: 'ApiPlatform\Tests\Fixtures\TestBundle\State\ContainNonResourceProvider'

tests/Functional/McpTest.php

@@ -405,6 +405,7 @@ public function testToolsList(): void
             ],
         ]);
 
+        self::assertResponseIsSuccessful();
         $data = $res->toArray();
         self::assertArrayHasKey('result', $data);
         self::assertArrayHasKey('tools', $data['result']);
@@ -418,14 +419,68 @@ public function testToolsList(): void
         self::assertContains('validate_input', $toolNames);
         self::assertContains('generate_markdown', $toolNames);
         self::assertContains('process_message', $toolNames);
+        self::assertContains('list_books', $toolNames);
 
         foreach ($tools as $tool) {
             self::assertArrayHasKey('name', $tool);
             self::assertArrayHasKey('inputSchema', $tool);
             self::assertEquals('object', $tool['inputSchema']['type']);
         }
 
-        self::assertResponseIsSuccessful();
+        $listBooks = array_filter($tools, static function (array $input) {
+            return 'list_books' === $input['name'];
+        });
+
+        self::assertCount(1, $listBooks);
+
+        $listBooks = array_first($listBooks);
+
+        self::assertArrayHasKeyAndValue('inputSchema', [
+            'type' => 'object',
+            'properties' => [
+                'search' => ['type' => 'string'],
+            ],
+        ], $listBooks);
+        self::assertArrayHasKeyAndValue('description', 'List Books', $listBooks);
+
+        $outputSchema = $listBooks['outputSchema'];
+        self::assertArrayHasKeyAndValue('$schema', 'http://json-schema.org/draft-07/schema#', $outputSchema);
+        self::assertArrayHasKeyAndValue('type', 'object', $outputSchema);
+
+        self::assertArrayHasKey('definitions', $outputSchema);
+        $definitions = $outputSchema['definitions'];
+        self::assertArrayHasKey('McpBook.jsonld', $definitions);
+        $McpBookJsonLd = $definitions['McpBook.jsonld'];
+        self::assertArrayHasKeyAndValue('allOf', [
+            [
+                '$ref' => '#/definitions/HydraItemBaseSchema',
+            ],
+            [
+                'type' => 'object',
+                'properties' => [
+                    'id' => ['readOnly' => true, 'type' => 'integer'],
+                    'title' => ['type' => 'string'],
+                    'isbn' => ['type' => 'string'],
+                    'status' => ['type' => ['string', 'null']],
+                ],
+            ],
+        ], $McpBookJsonLd);
+
+        self::assertArrayHasKeyAndValue('allOf', [
+            ['$ref' => '#/definitions/HydraCollectionBaseSchema'],
+            [
+                'type' => 'object',
+                'required' => ['hydra:member'],
+                'properties' => [
+                    'hydra:member' => [
+                        'type' => 'array',
+                        'items' => [
+                            '$ref' => '#/definitions/McpBook.jsonld',
+                        ],
+                    ],
+                ],
+            ],
+        ], $outputSchema);
     }
 
     public function testMcpToolAttribute(): void
@@ -651,4 +706,88 @@ public function testMcpMarkdownContent(): void
         self::assertStringContainsString("echo 'Hello, World!';", $content);
         self::assertStringContainsString('```', $content);
     }
+
+    public function testMcpListBooks(): void
+    {
+        if (!class_exists(McpBundle::class)) {
+            $this->markTestSkipped('MCP bundle is not installed');
+        }
+
+        if ($this->isMongoDB()) {
+            $this->markTestSkipped('MCP is not supported with MongoDB');
+        }
+
+        if (!$this->isPsr17FactoryAvailable()) {
+            $this->markTestSkipped('PSR-17 HTTP factory implementation not available (required for MCP)');
+        }
+
+        $this->recreateSchema([
+            McpBook::class,
+        ]);
+
+        $book = new McpBook();
+        $book->setTitle('API Platform Guide for MCP');
+        $book->setIsbn('1-528491');
+        $book->setStatus('available');
+        $manager = $this->getContainer()->get('doctrine.orm.entity_manager');
+        $manager->persist($book);
+        $manager->flush();
+
+        $client = self::createClient();
+        $sessionId = $this->initializeMcpSession($client);
+
+        $res = $client->request('POST', '/mcp', [
+            'headers' => [
+                'Accept' => 'application/json, text/event-stream',
+                'Content-Type' => 'application/json',
+                'mcp-session-id' => $sessionId,
+            ],
+            'json' => [
+                'jsonrpc' => '2.0',
+                'id' => 2,
+                'method' => 'tools/call',
+                'params' => [
+                    'name' => 'list_books',
+                    'arguments' => [
+                        'search' => '',
+                    ],
+                ],
+            ],
+        ]);
+
+        self::assertResponseIsSuccessful();
+        $result = $res->toArray()['result'] ?? null;
+        self::assertIsArray($result);
+        self::assertArrayHasKey('content', $result);
+        $content = $result['content'][0]['text'] ?? null;
+        self::assertNotNull($content, 'No text content in result');
+        self::assertStringContainsString('API Platform Guide for MCP', $content);
+        self::assertStringContainsString('1-528491', $content);
+
+        $structuredContent = $result['structuredContent'] ?? null;
+        $this->assertIsArray($structuredContent);
+
+        // when api_platform.use_symfony_listeners is true, the result is formatted as JSON-LD
+        if (true === $this->getContainer()->getParameter('api_platform.use_symfony_listeners')) {
+            self::assertArrayHasKeyAndValue('@context', '/contexts/McpBook', $structuredContent);
+            self::assertArrayHasKeyAndValue('hydra:totalItems', 1, $structuredContent);
+            $members = $structuredContent['hydra:member'];
+        } else {
+            $members = $structuredContent;
+        }
+
+        $this->assertCount(1, $members, json_encode($members, \JSON_PRETTY_PRINT));
+        $actualBook = array_first($members);
+
+        self::assertArrayHasKeyAndValue('id', 1, $actualBook);
+        self::assertArrayHasKeyAndValue('title', 'API Platform Guide for MCP', $actualBook);
+        self::assertArrayHasKeyAndValue('isbn', '1-528491', $actualBook);
+        self::assertArrayHasKeyAndValue('status', 'available', $actualBook);
+    }
+
+    private static function assertArrayHasKeyAndValue(string $key, mixed $value, array $data): void
+    {
+        self::assertArrayHasKey($key, $data);
+        self::assertSame($value, $data[$key]);
+    }
 }