fix(mcp): skip ToolProvider mapping when the request carries no tool payload

.github/workflows/ci.yml

@@ -375,6 +375,7 @@ jobs:
           - api-platform/openapi
           - api-platform/graphql
           - api-platform/http-cache
+          - api-platform/mcp
           - api-platform/ramsey-uuid
           - api-platform/serializer
           - api-platform/state

src/Mcp/State/ToolProvider.php

@@ -30,7 +30,7 @@ public function __construct(private readonly ObjectMapperInterface $objectMapper
 
     public function provide(Operation $operation, array $uriVariables = [], array $context = []): object|array|null
     {
-        if (!isset($context['mcp_request'])) {
+        if (!isset($context['mcp_request'], $context['mcp_data'])) {
             return null;
         }
 

src/Mcp/Tests/State/ToolProviderTest.php

@@ -0,0 +1,42 @@
+<?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\Mcp\Tests\State;
+
+use ApiPlatform\Mcp\State\ToolProvider;
+use ApiPlatform\Metadata\McpResource;
+use Mcp\Schema\Request\ReadResourceRequest;
+use PHPUnit\Framework\TestCase;
+use Symfony\Component\ObjectMapper\ObjectMapperInterface;
+
+class ToolProviderTest extends TestCase
+{
+    /**
+     * The handler installs this provider on every MCP operation that declares none,
+     * MCP resources included, but it only fills `mcp_data` for a tool call: reading
+     * a resource must not be mapped from a payload that does not exist.
+     */
+    public function testProvideReturnsNullWhenTheRequestCarriesNoToolPayload(): void
+    {
+        $objectMapper = $this->createMock(ObjectMapperInterface::class);
+        $objectMapper->expects($this->never())->method('map');
+
+        $provider = new ToolProvider($objectMapper);
+
+        $operation = new McpResource(uri: 'dummy://docs', name: 'docs', class: \stdClass::class);
+
+        $this->assertNull($provider->provide($operation, [], [
+            'mcp_request' => new ReadResourceRequest('dummy://docs'),
+        ]));
+    }
+}

src/Mcp/composer.json

@@ -30,12 +30,17 @@
         "php": ">=8.2",
         "api-platform/metadata": "^5.0@alpha",
         "api-platform/json-schema": "^5.0@alpha",
+        "api-platform/state": "^5.0@alpha",
         "mcp/sdk": "^0.8",
+        "psr/log": "^1.0 || ^2.0 || ^3.0",
+        "symfony/http-foundation": "^7.4 || ^8.0",
         "symfony/object-mapper": "^7.4 || ^8.0",
-        "symfony/polyfill-php85": "^1.32"
+        "symfony/polyfill-php85": "^1.32",
+        "symfony/serializer": "^7.4 || ^8.0"
     },
     "require-dev": {
-        "phpunit/phpunit": "^11.5 || ^12.2"
+        "phpunit/phpunit": "^11.5 || ^12.2",
+        "symfony/expression-language": "^7.4 || ^8.0"
     },
     "autoload": {
         "psr-4": {
@@ -60,6 +65,12 @@
             "url": "https://github.com/api-platform/api-platform"
         }
     },
+    "suggest": {
+        "symfony/expression-language": "To use the operation-level \"security\" expressions."
+    },
+    "scripts": {
+        "test": "./vendor/bin/phpunit"
+    },
     "minimum-stability": "beta",
     "prefer-stable": true
 }