Introduce Capability Registry & Discovery

tests/Capability/Attribute/McpToolTest.php

@@ -0,0 +1,52 @@
+<?php
+
+/*
+ * This file is part of the official PHP MCP SDK.
+ *
+ * A collaboration between Symfony and the PHP Foundation.
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Mcp\Tests\Capability\Attribute;
+
+use Mcp\Capability\Attribute\McpTool;
+use PHPUnit\Framework\TestCase;
+
+class McpToolTest extends TestCase
+{
+    public function testInstantiatesWithCorrectProperties(): void
+    {
+        // Arrange
+        $name = 'test-tool-name';
+        $description = 'This is a test description.';
+
+        // Act
+        $attribute = new McpTool(name: $name, description: $description);
+
+        // Assert
+        $this->assertSame($name, $attribute->name);
+        $this->assertSame($description, $attribute->description);
+    }
+
+    public function testInstantiatesWithNullValuesForNameAndDescription(): void
+    {
+        // Arrange & Act
+        $attribute = new McpTool(name: null, description: null);
+
+        // Assert
+        $this->assertNull($attribute->name);
+        $this->assertNull($attribute->description);
+    }
+
+    public function testInstantiatesWithMissingOptionalArguments(): void
+    {
+        // Arrange & Act
+        $attribute = new McpTool(); // Use default constructor values
+
+        // Assert
+        $this->assertNull($attribute->name);
+        $this->assertNull($attribute->description);
+    }
+}