diff --git a/README.md b/README.md
index 42e41cb..4870d13 100644
--- a/README.md
+++ b/README.md
@@ -757,7 +757,11 @@ Completion providers enable MCP clients to offer auto-completion suggestions in
 
 > **Note**: Tools and resources can be discovered via standard MCP commands (`tools/list`, `resources/list`), so completion providers are not needed for them. Completion providers are used only for resource templates (URI variables) and prompt arguments.
 
-Completion providers must implement the `CompletionProviderInterface`:
+The `#[CompletionProvider]` attribute supports three types of completion sources:
+
+#### 1. Custom Provider Classes
+
+For complex completion logic, implement the `CompletionProviderInterface`:
 
 ```php
 use PhpMcp\Server\Contracts\CompletionProviderInterface;
@@ -766,13 +770,12 @@ use PhpMcp\Server\Attributes\{McpResourceTemplate, CompletionProvider};
 
 class UserIdCompletionProvider implements CompletionProviderInterface
 {
+    public function __construct(private DatabaseService $db) {}
+
     public function getCompletions(string $currentValue, SessionInterface $session): array
     {
-        // Return completion suggestions based on current input
-        $allUsers = ['user_1', 'user_2', 'user_3', 'admin_user'];
-        
-        // Filter based on what user has typed so far
-        return array_filter($allUsers, fn($user) => str_starts_with($user, $currentValue));
+        // Dynamic completion from database
+        return $this->db->searchUsers($currentValue);
     }
 }
 
@@ -780,20 +783,130 @@ class UserService
 {
     #[McpResourceTemplate(uriTemplate: 'user://{userId}/profile')]
     public function getUserProfile(
-        #[CompletionProvider(UserIdCompletionProvider::class)]
+        #[CompletionProvider(provider: UserIdCompletionProvider::class)]  // Class string - resolved from container
         string $userId
     ): array {
-        // Always validate input even with completion providers
-        // Users can still pass any value regardless of completion suggestions
-        if (!$this->isValidUserId($userId)) {
-            throw new \InvalidArgumentException('Invalid user ID provided');
-        }
-        
         return ['id' => $userId, 'name' => 'John Doe'];
     }
 }
 ```
 
+You can also pass pre-configured provider instances:
+
+```php
+class DocumentService  
+{
+    #[McpPrompt(name: 'document_prompt')]
+    public function generatePrompt(
+        #[CompletionProvider(provider: new UserIdCompletionProvider($database))]  // Pre-configured instance
+        string $userId,
+        
+        #[CompletionProvider(provider: $this->categoryProvider)]  // Instance from property
+        string $category
+    ): array {
+        return [['role' => 'user', 'content' => "Generate document for user {$userId} in {$category}"]];
+    }
+}
+```
+
+#### 2. Simple List Completions
+
+For static completion lists, use the `values` parameter:
+
+```php
+use PhpMcp\Server\Attributes\{McpPrompt, CompletionProvider};
+
+class ContentService
+{
+    #[McpPrompt(name: 'content_generator')]
+    public function generateContent(
+        #[CompletionProvider(values: ['blog', 'article', 'tutorial', 'guide', 'documentation'])]
+        string $contentType,
+        
+        #[CompletionProvider(values: ['beginner', 'intermediate', 'advanced', 'expert'])]
+        string $difficulty
+    ): array {
+        return [['role' => 'user', 'content' => "Create a {$difficulty} level {$contentType}"]];
+    }
+}
+```
+
+#### 3. Enum-Based Completions
+
+For enum classes, use the `enum` parameter:
+
+```php
+enum Priority: string
+{
+    case LOW = 'low';
+    case MEDIUM = 'medium';
+    case HIGH = 'high';
+    case CRITICAL = 'critical';
+}
+
+enum Status  // Unit enum (no backing values)
+{
+    case DRAFT;
+    case PUBLISHED;
+    case ARCHIVED;
+}
+
+class TaskService
+{
+    #[McpTool(name: 'create_task')]
+    public function createTask(
+        string $title,
+        
+        #[CompletionProvider(enum: Priority::class)]  // String-backed enum uses values
+        string $priority,
+        
+        #[CompletionProvider(enum: Status::class)]    // Unit enum uses case names
+        string $status
+    ): array {
+        return ['id' => 123, 'title' => $title, 'priority' => $priority, 'status' => $status];
+    }
+}
+```
+
+#### Manual Registration with Completion Providers
+
+```php
+$server = Server::make()
+    ->withServerInfo('Completion Demo', '1.0.0')
+    
+    // Using provider class (resolved from container)
+    ->withPrompt(
+        [DocumentHandler::class, 'generateReport'],
+        name: 'document_report'
+        // Completion providers are auto-discovered from method attributes
+    )
+    
+    // Using closure with inline completion providers
+    ->withPrompt(
+        function(
+            #[CompletionProvider(values: ['json', 'xml', 'csv', 'yaml'])]
+            string $format,
+            
+            #[CompletionProvider(enum: Priority::class)]
+            string $priority
+        ): array {
+            return [['role' => 'user', 'content' => "Export data in {$format} format with {$priority} priority"]];
+        },
+        name: 'export_data'
+    )
+    
+    ->build();
+```
+
+#### Completion Provider Resolution
+
+The server automatically handles provider resolution:
+
+- **Class strings** (`MyProvider::class`) → Resolved from PSR-11 container with dependency injection
+- **Instances** (`new MyProvider()`) → Used directly as-is
+- **Values arrays** (`['a', 'b', 'c']`) → Automatically wrapped in `ListCompletionProvider`
+- **Enum classes** (`MyEnum::class`) → Automatically wrapped in `EnumCompletionProvider`
+
 > **Important**: Completion providers only offer suggestions to users in the MCP client interface. Users can still input any value, so always validate parameters in your handlers regardless of completion provider constraints.
 
 ### Custom Dependency Injection
diff --git a/examples/02-discovery-http-userprofile/McpElements.php b/examples/02-discovery-http-userprofile/McpElements.php
index d371713..f684814 100644
--- a/examples/02-discovery-http-userprofile/McpElements.php
+++ b/examples/02-discovery-http-userprofile/McpElements.php
@@ -43,7 +43,7 @@ public function __construct(LoggerInterface $logger)
     )]
 
     public function getUserProfile(
-        #[CompletionProvider(providerClass: UserIdCompletionProvider::class)]
+        #[CompletionProvider(values: ['101', '102', '103'])]
         string $userId
     ): array {
         $this->logger->info('Reading resource: user profile', ['userId' => $userId]);
@@ -116,7 +116,7 @@ public function testToolWithoutParams()
      */
     #[McpPrompt(name: 'generate_bio_prompt')]
     public function generateBio(
-        #[CompletionProvider(providerClass: UserIdCompletionProvider::class)]
+        #[CompletionProvider(provider: UserIdCompletionProvider::class)]
         string $userId,
         string $tone = 'professional'
     ): array {
diff --git a/src/Attributes/CompletionProvider.php b/src/Attributes/CompletionProvider.php
index 3bf5223..eb5034a 100644
--- a/src/Attributes/CompletionProvider.php
+++ b/src/Attributes/CompletionProvider.php
@@ -11,9 +11,15 @@
 class CompletionProvider
 {
     /**
-     * @param class-string<CompletionProviderInterface> $providerClass FQCN of the completion provider class.
+     * @param class-string<CompletionProviderInterface>|CompletionProviderInterface|null $provider If a class-string, it will be resolved from the container at the point of use.
      */
-    public function __construct(public string $providerClass)
-    {
+    public function __construct(
+        public string|CompletionProviderInterface|null $provider = null,
+        public ?array $values = null,
+        public ?string $enum = null,
+    ) {
+        if (count(array_filter([$provider, $values, $enum])) !== 1) {
+            throw new \InvalidArgumentException('Only one of provider, values, or enum can be set');
+        }
     }
 }
diff --git a/src/Defaults/EnumCompletionProvider.php b/src/Defaults/EnumCompletionProvider.php
new file mode 100644
index 0000000..a8244e9
--- /dev/null
+++ b/src/Defaults/EnumCompletionProvider.php
@@ -0,0 +1,37 @@
+<?php
+
+declare(strict_types=1);
+
+namespace PhpMcp\Server\Defaults;
+
+use PhpMcp\Server\Contracts\CompletionProviderInterface;
+use PhpMcp\Server\Contracts\SessionInterface;
+
+class EnumCompletionProvider implements CompletionProviderInterface
+{
+    private array $values;
+
+    public function __construct(string $enumClass)
+    {
+        if (!enum_exists($enumClass)) {
+            throw new \InvalidArgumentException("Class {$enumClass} is not an enum");
+        }
+
+        $this->values = array_map(
+            fn($case) => isset($case->value) && is_string($case->value) ? $case->value : $case->name,
+            $enumClass::cases()
+        );
+    }
+
+    public function getCompletions(string $currentValue, SessionInterface $session): array
+    {
+        if (empty($currentValue)) {
+            return $this->values;
+        }
+
+        return array_values(array_filter(
+            $this->values,
+            fn(string $value) => str_starts_with($value, $currentValue)
+        ));
+    }
+}
diff --git a/src/Defaults/ListCompletionProvider.php b/src/Defaults/ListCompletionProvider.php
new file mode 100644
index 0000000..1b1d377
--- /dev/null
+++ b/src/Defaults/ListCompletionProvider.php
@@ -0,0 +1,25 @@
+<?php
+
+declare(strict_types=1);
+
+namespace PhpMcp\Server\Defaults;
+
+use PhpMcp\Server\Contracts\CompletionProviderInterface;
+use PhpMcp\Server\Contracts\SessionInterface;
+
+class ListCompletionProvider implements CompletionProviderInterface
+{
+    public function __construct(private array $values) {}
+
+    public function getCompletions(string $currentValue, SessionInterface $session): array
+    {
+        if (empty($currentValue)) {
+            return $this->values;
+        }
+
+        return array_values(array_filter(
+            $this->values,
+            fn(string $value) => str_starts_with($value, $currentValue)
+        ));
+    }
+}
diff --git a/src/Dispatcher.php b/src/Dispatcher.php
index 590443a..e52aae6 100644
--- a/src/Dispatcher.php
+++ b/src/Dispatcher.php
@@ -340,7 +340,7 @@ public function handleCompletionComplete(CompletionCompleteRequest $request, Ses
                 throw McpServerException::invalidParams("Argument '{$argumentName}' not found in prompt '{$identifier}'.");
             }
 
-            $providerClass = $registeredPrompt->getCompletionProvider($argumentName);
+            return $registeredPrompt->complete($this->container, $argumentName, $currentValue, $session);
         } elseif ($ref->type === 'ref/resource') {
             $identifier = $ref->uri;
             $registeredResourceTemplate = $this->registry->getResourceTemplate($identifier);
@@ -360,26 +360,10 @@ public function handleCompletionComplete(CompletionCompleteRequest $request, Ses
                 throw McpServerException::invalidParams("URI variable '{$argumentName}' not found in resource template '{$identifier}'.");
             }
 
-            $providerClass = $registeredResourceTemplate->getCompletionProvider($argumentName);
+            return $registeredResourceTemplate->complete($this->container, $argumentName, $currentValue, $session);
         } else {
             throw McpServerException::invalidParams("Invalid ref type '{$ref->type}' for completion complete request.");
         }
-
-        if (! $providerClass) {
-            $this->logger->warning("No completion provider found for argument '{$argumentName}' in '{$ref->type}' '{$identifier}'.");
-            return new CompletionCompleteResult([]);
-        }
-
-        $provider = $this->container->get($providerClass);
-
-        $completions = $provider->getCompletions($currentValue, $session);
-
-        $total = count($completions);
-        $hasMore = $total > 100;
-
-        $pagedCompletions = array_slice($completions, 0, 100);
-
-        return new CompletionCompleteResult($pagedCompletions, $total, $hasMore);
     }
 
     public function handleNotificationInitialized(InitializedNotification $notification, SessionInterface $session): EmptyResult
diff --git a/src/Elements/RegisteredPrompt.php b/src/Elements/RegisteredPrompt.php
index 9e421bd..b37ad1e 100644
--- a/src/Elements/RegisteredPrompt.php
+++ b/src/Elements/RegisteredPrompt.php
@@ -14,6 +14,9 @@
 use PhpMcp\Schema\Content\TextContent;
 use PhpMcp\Schema\Content\TextResourceContents;
 use PhpMcp\Schema\Enum\Role;
+use PhpMcp\Schema\Result\CompletionCompleteResult;
+use PhpMcp\Server\Contracts\CompletionProviderInterface;
+use PhpMcp\Server\Contracts\SessionInterface;
 use Psr\Container\ContainerInterface;
 use Throwable;
 
@@ -47,9 +50,31 @@ public function get(ContainerInterface $container, array $arguments): array
         return $this->formatResult($result);
     }
 
-    public function getCompletionProvider(string $argumentName): ?string
+    public function complete(ContainerInterface $container, string $argument, string $value, SessionInterface $session): CompletionCompleteResult
     {
-        return $this->completionProviders[$argumentName] ?? null;
+        $providerClassOrInstance = $this->completionProviders[$argument] ?? null;
+        if ($providerClassOrInstance === null) {
+            return new CompletionCompleteResult([]);
+        }
+
+        if (is_string($providerClassOrInstance)) {
+            if (! class_exists($providerClassOrInstance)) {
+                throw new \RuntimeException("Completion provider class '{$providerClassOrInstance}' does not exist.");
+            }
+
+            $provider = $container->get($providerClassOrInstance);
+        } else {
+            $provider = $providerClassOrInstance;
+        }
+
+        $completions = $provider->getCompletions($value, $session);
+
+        $total = count($completions);
+        $hasMore = $total > 100;
+
+        $pagedCompletions = array_slice($completions, 0, 100);
+
+        return new CompletionCompleteResult($pagedCompletions, $total, $hasMore);
     }
 
     /**
@@ -268,9 +293,14 @@ private function formatResourceContent(array $content, string $indexStr): Embedd
 
     public function toArray(): array
     {
+        $completionProviders = [];
+        foreach ($this->completionProviders as $argument => $provider) {
+            $completionProviders[$argument] = serialize($provider);
+        }
+
         return [
             'schema' => $this->schema->toArray(),
-            'completionProviders' => $this->completionProviders,
+            'completionProviders' => $completionProviders,
             ...parent::toArray(),
         ];
     }
@@ -282,11 +312,16 @@ public static function fromArray(array $data): self|false
                 return false;
             }
 
+            $completionProviders = [];
+            foreach ($data['completionProviders'] ?? [] as $argument => $provider) {
+                $completionProviders[$argument] = unserialize($provider);
+            }
+
             return new self(
                 Prompt::fromArray($data['schema']),
                 $data['handler'],
                 $data['isManual'] ?? false,
-                $data['completionProviders'] ?? [],
+                $completionProviders,
             );
         } catch (Throwable $e) {
             return false;
diff --git a/src/Elements/RegisteredResourceTemplate.php b/src/Elements/RegisteredResourceTemplate.php
index b431f78..e88c9ab 100644
--- a/src/Elements/RegisteredResourceTemplate.php
+++ b/src/Elements/RegisteredResourceTemplate.php
@@ -9,6 +9,8 @@
 use PhpMcp\Schema\Content\ResourceContents;
 use PhpMcp\Schema\Content\TextResourceContents;
 use PhpMcp\Schema\ResourceTemplate;
+use PhpMcp\Schema\Result\CompletionCompleteResult;
+use PhpMcp\Server\Contracts\SessionInterface;
 use Psr\Container\ContainerInterface;
 use Throwable;
 
@@ -48,11 +50,34 @@ public function read(ContainerInterface $container, string $uri): array
         return $this->formatResult($result, $uri, $this->schema->mimeType);
     }
 
-    public function getCompletionProvider(string $argumentName): ?string
+    public function complete(ContainerInterface $container, string $argument, string $value, SessionInterface $session): CompletionCompleteResult
     {
-        return $this->completionProviders[$argumentName] ?? null;
+        $providerClassOrInstance = $this->completionProviders[$argument] ?? null;
+        if ($providerClassOrInstance === null) {
+            return new CompletionCompleteResult([]);
+        }
+
+        if (is_string($providerClassOrInstance)) {
+            if (! class_exists($providerClassOrInstance)) {
+                throw new \RuntimeException("Completion provider class '{$providerClassOrInstance}' does not exist.");
+            }
+
+            $provider = $container->get($providerClassOrInstance);
+        } else {
+            $provider = $providerClassOrInstance;
+        }
+
+        $completions = $provider->getCompletions($value, $session);
+
+        $total = count($completions);
+        $hasMore = $total > 100;
+
+        $pagedCompletions = array_slice($completions, 0, 100);
+
+        return new CompletionCompleteResult($pagedCompletions, $total, $hasMore);
     }
 
+
     public function getVariableNames(): array
     {
         return $this->variableNames;
@@ -265,9 +290,14 @@ private function guessMimeTypeFromString(string $content): string
 
     public function toArray(): array
     {
+        $completionProviders = [];
+        foreach ($this->completionProviders as $argument => $provider) {
+            $completionProviders[$argument] = serialize($provider);
+        }
+
         return [
             'schema' => $this->schema->toArray(),
-            'completionProviders' => $this->completionProviders,
+            'completionProviders' => $completionProviders,
             ...parent::toArray(),
         ];
     }
@@ -279,11 +309,16 @@ public static function fromArray(array $data): self|false
                 return false;
             }
 
+            $completionProviders = [];
+            foreach ($data['completionProviders'] ?? [] as $argument => $provider) {
+                $completionProviders[$argument] = unserialize($provider);
+            }
+
             return new self(
                 ResourceTemplate::fromArray($data['schema']),
                 $data['handler'],
                 $data['isManual'] ?? false,
-                $data['completionProviders'] ?? [],
+                $completionProviders,
             );
         } catch (Throwable $e) {
             return false;
diff --git a/src/ServerBuilder.php b/src/ServerBuilder.php
index 4f8028b..c81234f 100644
--- a/src/ServerBuilder.php
+++ b/src/ServerBuilder.php
@@ -17,6 +17,8 @@
 use PhpMcp\Server\Attributes\CompletionProvider;
 use PhpMcp\Server\Contracts\SessionHandlerInterface;
 use PhpMcp\Server\Defaults\BasicContainer;
+use PhpMcp\Server\Defaults\EnumCompletionProvider;
+use PhpMcp\Server\Defaults\ListCompletionProvider;
 use PhpMcp\Server\Exception\ConfigurationException;
 
 use PhpMcp\Server\Session\ArraySessionHandler;
@@ -506,7 +508,14 @@ private function getCompletionProviders(\ReflectionMethod|\ReflectionFunction $r
             $completionAttributes = $param->getAttributes(CompletionProvider::class, \ReflectionAttribute::IS_INSTANCEOF);
             if (!empty($completionAttributes)) {
                 $attributeInstance = $completionAttributes[0]->newInstance();
-                $completionProviders[$param->getName()] = $attributeInstance->providerClass;
+
+                if ($attributeInstance->provider) {
+                    $completionProviders[$param->getName()] = $attributeInstance->provider;
+                } elseif ($attributeInstance->values) {
+                    $completionProviders[$param->getName()] = new ListCompletionProvider($attributeInstance->values);
+                } elseif ($attributeInstance->enum) {
+                    $completionProviders[$param->getName()] = new EnumCompletionProvider($attributeInstance->enum);
+                }
             }
         }
 
diff --git a/src/Utils/Discoverer.php b/src/Utils/Discoverer.php
index 1a73998..8d28cc2 100644
--- a/src/Utils/Discoverer.php
+++ b/src/Utils/Discoverer.php
@@ -14,6 +14,8 @@
 use PhpMcp\Server\Attributes\McpResource;
 use PhpMcp\Server\Attributes\McpResourceTemplate;
 use PhpMcp\Server\Attributes\McpTool;
+use PhpMcp\Server\Defaults\EnumCompletionProvider;
+use PhpMcp\Server\Defaults\ListCompletionProvider;
 use PhpMcp\Server\Exception\McpServerException;
 use PhpMcp\Server\Registry;
 use Psr\Log\LoggerInterface;
@@ -263,7 +265,14 @@ private function getCompletionProviders(\ReflectionMethod $reflectionMethod): ar
             $completionAttributes = $param->getAttributes(CompletionProvider::class, \ReflectionAttribute::IS_INSTANCEOF);
             if (!empty($completionAttributes)) {
                 $attributeInstance = $completionAttributes[0]->newInstance();
-                $completionProviders[$param->getName()] = $attributeInstance->providerClass;
+
+                if ($attributeInstance->provider) {
+                    $completionProviders[$param->getName()] = $attributeInstance->provider;
+                } elseif ($attributeInstance->values) {
+                    $completionProviders[$param->getName()] = new ListCompletionProvider($attributeInstance->values);
+                } elseif ($attributeInstance->enum) {
+                    $completionProviders[$param->getName()] = new EnumCompletionProvider($attributeInstance->enum);
+                }
             }
         }
 
diff --git a/test_closure_support.php b/test_closure_support.php
deleted file mode 100644
index 946cb76..0000000
--- a/test_closure_support.php
+++ /dev/null
@@ -1,258 +0,0 @@
-<?php
-
-require_once __DIR__ . '/vendor/autoload.php';
-
-use PhpMcp\Server\ServerBuilder;
-use PhpMcp\Schema\Implementation;
-use PhpMcp\Schema\Content\TextContent;
-use PhpMcp\Schema\Content\PromptMessage;
-use PhpMcp\Schema\Enum\Role;
-use Psr\Container\ContainerInterface;
-
-// Create a simple container for testing
-class TestContainer implements ContainerInterface
-{
-    private array $services = [];
-
-    public function get(string $id)
-    {
-        return $this->services[$id] ?? new $id();
-    }
-
-    public function has(string $id): bool
-    {
-        return isset($this->services[$id]) || class_exists($id);
-    }
-
-    public function set(string $id, object $service): void
-    {
-        $this->services[$id] = $service;
-    }
-}
-
-// Create a test closure tool
-$calculateTool = function (int $a, int $b, string $operation = 'add'): string {
-    return match ($operation) {
-        'add' => "Result: " . ($a + $b),
-        'subtract' => "Result: " . ($a - $b),
-        'multiply' => "Result: " . ($a * $b),
-        'divide' => $b !== 0 ? "Result: " . ($a / $b) : "Cannot divide by zero",
-        default => "Unknown operation: $operation"
-    };
-};
-
-// Create a test closure resource
-$configResource = function (string $uri): array {
-    return [
-        new TextContent("Configuration for URI: $uri"),
-        new TextContent("Environment: development"),
-        new TextContent("Version: 1.0.0")
-    ];
-};
-
-// Create a test closure prompt
-$codeGenPrompt = function (string $language, string $description): array {
-    return [
-        PromptMessage::make(
-            Role::User,
-            new TextContent("Generate $language code for: $description")
-        )
-    ];
-};
-
-// Create a test closure resource template
-$dynamicResource = function (string $uri, string $id): array {
-    return [
-        new TextContent("Dynamic resource ID: $id"),
-        new TextContent("Requested URI: $uri"),
-        new TextContent("Generated at: " . date('Y-m-d H:i:s'))
-    ];
-};
-
-// Test static method support
-class StaticToolHandler
-{
-    public static function getCurrentTime(): string
-    {
-        return "Current time: " . date('Y-m-d H:i:s');
-    }
-}
-
-// Test instance method support
-class InstanceToolHandler
-{
-    private string $prefix;
-
-    public function __construct(string $prefix = "Instance")
-    {
-        $this->prefix = $prefix;
-    }
-
-    public function greet(string $name): string
-    {
-        return "{$this->prefix}: Hello, $name!";
-    }
-}
-
-echo "🧪 Testing MCP Server Closure and Callable Support\n";
-echo "=" . str_repeat("=", 50) . "\n\n";
-
-// Build the server with various handler types
-$container = new TestContainer();
-$container->set(InstanceToolHandler::class, new InstanceToolHandler("TestInstance"));
-
-$server = (new ServerBuilder())
-    ->withServerInfo('ClosureTest', '1.0.0')
-    ->withContainer($container)
-    ->withTool($calculateTool, 'calculator', 'Performs basic mathematical operations')
-    ->withResource($configResource, 'config://app', 'app_config', 'Gets app configuration')
-    ->withResourceTemplate($dynamicResource, 'dynamic://item/{id}', 'dynamic_item', 'Gets dynamic items by ID')
-    ->withPrompt($codeGenPrompt, 'code_generator', 'Generates code in specified language')
-    ->withTool([StaticToolHandler::class, 'getCurrentTime'], 'current_time', 'Gets current server time')
-    ->withTool([InstanceToolHandler::class, 'greet'], 'greeter', 'Greets a person')
-    ->build();
-
-echo "✅ Server built successfully with various handler types!\n\n";
-
-// Get the registry using reflection
-$registryProperty = new ReflectionProperty($server, 'registry');
-$registryProperty->setAccessible(true);
-$registry = $registryProperty->getValue($server);
-
-// Test Tools
-echo "🔧 Testing Tools:\n";
-echo "-" . str_repeat("-", 20) . "\n";
-
-// Test closure tool
-$calculatorTool = $registry->getTool('calculator');
-if ($calculatorTool) {
-    try {
-        $result = $calculatorTool->call($container, ['a' => 10, 'b' => 5, 'operation' => 'add']);
-        echo "✅ Closure Tool (calculator): " . $result[0]->text . "\n";
-
-        $result = $calculatorTool->call($container, ['a' => 10, 'b' => 3, 'operation' => 'multiply']);
-        echo "✅ Closure Tool (calculator): " . $result[0]->text . "\n";
-    } catch (Exception $e) {
-        echo "❌ Closure Tool failed: " . $e->getMessage() . "\n";
-    }
-} else {
-    echo "❌ Calculator tool not found\n";
-}
-
-// Test static method tool
-$timeTool = $registry->getTool('current_time');
-if ($timeTool) {
-    try {
-        $result = $timeTool->call($container, []);
-        echo "✅ Static Method Tool (current_time): " . $result[0]->text . "\n";
-    } catch (Exception $e) {
-        echo "❌ Static Method Tool failed: " . $e->getMessage() . "\n";
-    }
-} else {
-    echo "❌ Current time tool not found\n";
-}
-
-// Test instance method tool
-$greeterTool = $registry->getTool('greeter');
-if ($greeterTool) {
-    try {
-        $result = $greeterTool->call($container, ['name' => 'Alice']);
-        echo "✅ Instance Method Tool (greeter): " . $result[0]->text . "\n";
-    } catch (Exception $e) {
-        echo "❌ Instance Method Tool failed: " . $e->getMessage() . "\n";
-    }
-} else {
-    echo "❌ Greeter tool not found\n";
-}
-
-// Test Resources
-echo "\n📁 Testing Resources:\n";
-echo "-" . str_repeat("-", 20) . "\n";
-
-// Test closure resource
-$configRes = $registry->getResource('config://app');
-if ($configRes) {
-    try {
-        $result = $configRes->read($container, 'config://app');
-        if (is_array($result) && isset($result[0])) {
-            echo "✅ Closure Resource (config): " . $result[0]->text . "\n";
-            if (isset($result[1])) echo "   └─ " . $result[1]->text . "\n";
-            if (isset($result[2])) echo "   └─ " . $result[2]->text . "\n";
-        } else {
-            echo "✅ Closure Resource (config): " . (is_string($result) ? $result : json_encode($result)) . "\n";
-        }
-    } catch (Exception $e) {
-        echo "❌ Closure Resource failed: " . $e->getMessage() . "\n";
-    }
-} else {
-    echo "❌ Config resource not found\n";
-}
-
-// Test Resource Templates
-echo "\n📋 Testing Resource Templates:\n";
-echo "-" . str_repeat("-", 30) . "\n";
-
-// Test closure resource template
-$dynamicRes = $registry->getResource('dynamic://item/123');
-if ($dynamicRes) {
-    try {
-        $result = $dynamicRes->read($container, 'dynamic://item/123');
-        if (is_array($result) && isset($result[0])) {
-            echo "✅ Closure Resource Template (dynamic): " . $result[0]->text . "\n";
-            if (isset($result[1])) echo "   └─ " . $result[1]->text . "\n";
-            if (isset($result[2])) echo "   └─ " . $result[2]->text . "\n";
-        } else {
-            echo "✅ Closure Resource Template (dynamic): " . (is_string($result) ? $result : json_encode($result)) . "\n";
-        }
-    } catch (Exception $e) {
-        echo "❌ Closure Resource Template failed: " . $e->getMessage() . "\n";
-    }
-} else {
-    echo "❌ Dynamic resource template not found\n";
-}
-
-// Test Prompts
-echo "\n💬 Testing Prompts:\n";
-echo "-" . str_repeat("-", 20) . "\n";
-
-// Test closure prompt
-$codePrompt = $registry->getPrompt('code_generator');
-if ($codePrompt) {
-    try {
-        $result = $codePrompt->get($container, ['language' => 'PHP', 'description' => 'a calculator function']);
-        if (is_array($result) && isset($result[0])) {
-            // Result is an array of PromptMessage objects
-            $message = $result[0];
-            if ($message instanceof \PhpMcp\Schema\Content\PromptMessage) {
-                echo "✅ Closure Prompt (code_generator): " . $message->content->text . "\n";
-            } else {
-                echo "✅ Closure Prompt (code_generator): " . json_encode($result) . "\n";
-            }
-        } else {
-            echo "✅ Closure Prompt (code_generator): " . (is_string($result) ? $result : json_encode($result)) . "\n";
-        }
-    } catch (Exception $e) {
-        echo "❌ Closure Prompt failed: " . $e->getMessage() . "\n";
-    }
-} else {
-    echo "❌ Code generator prompt not found\n";
-}
-
-// Summary
-echo "\n📊 Registry Summary:\n";
-echo "-" . str_repeat("-", 20) . "\n";
-$tools = $registry->getTools();
-$resources = $registry->getResources();
-$prompts = $registry->getPrompts();
-$templates = $registry->getResourceTemplates();
-
-echo "✅ Tools: " . count($tools) . "\n";
-echo "✅ Resources: " . count($resources) . "\n";
-echo "✅ Prompts: " . count($prompts) . "\n";
-echo "✅ Resource Templates: " . count($templates) . "\n";
-
-echo "\n🎉 All tests passed! Closure and callable support is working correctly.\n";
-echo "   ✓ Closures as handlers\n";
-echo "   ✓ Static methods as handlers\n";
-echo "   ✓ Instance methods as handlers\n";
-echo "   ✓ All handler types can be called successfully\n";
diff --git a/test_unique_closure_names.php b/test_unique_closure_names.php
deleted file mode 100644
index 90aafdd..0000000
--- a/test_unique_closure_names.php
+++ /dev/null
@@ -1,144 +0,0 @@
-<?php
-
-require_once __DIR__ . '/vendor/autoload.php';
-
-use PhpMcp\Server\ServerBuilder;
-use PhpMcp\Schema\Content\TextContent;
-
-echo "🧪 Testing Unique Closure Names\n";
-echo "=" . str_repeat("=", 35) . "\n\n";
-
-// Create multiple closure tools without explicit names
-$addTool = function (int $a, int $b): string {
-    return "Sum: " . ($a + $b);
-};
-
-$multiplyTool = function (int $x, int $y): string {
-    return "Product: " . ($x * $y);
-};
-
-$subtractTool = function (int $first, int $second): string {
-    return "Difference: " . ($first - $second);
-};
-
-// Create multiple closure prompts without explicit names
-$mathPrompt = function (string $operation): array {
-    return [
-        \PhpMcp\Schema\Content\PromptMessage::make(
-            \PhpMcp\Schema\Enum\Role::User,
-            new TextContent("Solve this $operation problem")
-        )
-    ];
-};
-
-$codePrompt = function (string $language): array {
-    return [
-        \PhpMcp\Schema\Content\PromptMessage::make(
-            \PhpMcp\Schema\Enum\Role::User,
-            new TextContent("Write code in $language")
-        )
-    ];
-};
-
-// Build server with multiple closures
-$server = (new ServerBuilder())
-    ->withServerInfo('UniqueNameTest', '1.0.0')
-    // Tools without explicit names - should get unique names
-    ->withTool($addTool)
-    ->withTool($multiplyTool)
-    ->withTool($subtractTool)
-    // Prompts without explicit names - should get unique names
-    ->withPrompt($mathPrompt)
-    ->withPrompt($codePrompt)
-    ->build();
-
-echo "✅ Server built successfully with multiple unnamed closures!\n\n";
-
-// Get the registry using reflection
-$registryProperty = new ReflectionProperty($server, 'registry');
-$registryProperty->setAccessible(true);
-$registry = $registryProperty->getValue($server);
-
-// Check tool names
-echo "🔧 Registered Tool Names:\n";
-echo "-" . str_repeat("-", 25) . "\n";
-$tools = $registry->getTools();
-foreach ($tools as $name => $tool) {
-    echo "  - $name: {$tool->description}\n";
-}
-
-// Check prompt names  
-echo "\n💬 Registered Prompt Names:\n";
-echo "-" . str_repeat("-", 27) . "\n";
-$prompts = $registry->getPrompts();
-foreach ($prompts as $name => $prompt) {
-    echo "  - $name: {$prompt->description}\n";
-}
-
-// Verify uniqueness
-echo "\n📊 Uniqueness Check:\n";
-echo "-" . str_repeat("-", 20) . "\n";
-$toolNames = array_keys($tools);
-$promptNames = array_keys($prompts);
-$allNames = array_merge($toolNames, $promptNames);
-
-$uniqueNames = array_unique($allNames);
-$totalNames = count($allNames);
-$uniqueCount = count($uniqueNames);
-
-echo "Total names: $totalNames\n";
-echo "Unique names: $uniqueCount\n";
-
-if ($totalNames === $uniqueCount) {
-    echo "✅ All names are unique!\n";
-} else {
-    echo "❌ Found duplicate names!\n";
-    $duplicates = array_diff_assoc($allNames, $uniqueNames);
-    foreach ($duplicates as $duplicate) {
-        echo "   Duplicate: $duplicate\n";
-    }
-}
-
-// Test that the same closure gets the same name consistently
-echo "\n🔄 Consistency Check:\n";
-echo "-" . str_repeat("-", 20) . "\n";
-
-$sameClosure = function (string $msg): string {
-    return "Echo: $msg";
-};
-
-$server1 = (new ServerBuilder())
-    ->withServerInfo('Test1', '1.0.0')
-    ->withTool($sameClosure)
-    ->build();
-
-$server2 = (new ServerBuilder())
-    ->withServerInfo('Test2', '1.0.0')
-    ->withTool($sameClosure)
-    ->build();
-
-// Get names from both servers
-$registry1Property = new ReflectionProperty($server1, 'registry');
-$registry1Property->setAccessible(true);
-$registry1 = $registry1Property->getValue($server1);
-
-$registry2Property = new ReflectionProperty($server2, 'registry');
-$registry2Property->setAccessible(true);
-$registry2 = $registry2Property->getValue($server2);
-
-$tools1 = $registry1->getTools();
-$tools2 = $registry2->getTools();
-
-$name1 = array_keys($tools1)[0];
-$name2 = array_keys($tools2)[0];
-
-echo "Same closure in server 1: $name1\n";
-echo "Same closure in server 2: $name2\n";
-
-if ($name1 === $name2) {
-    echo "✅ Same closure gets consistent name!\n";
-} else {
-    echo "❌ Same closure gets different names!\n";
-}
-
-echo "\n🎉 Unique naming test complete!\n";
diff --git a/tests/Fixtures/Discovery/DiscoverablePromptHandler.php b/tests/Fixtures/Discovery/DiscoverablePromptHandler.php
index 54d6a00..985cbe8 100644
--- a/tests/Fixtures/Discovery/DiscoverablePromptHandler.php
+++ b/tests/Fixtures/Discovery/DiscoverablePromptHandler.php
@@ -18,7 +18,7 @@ class DiscoverablePromptHandler
      */
     #[McpPrompt(name: "creative_story_prompt")]
     public function generateStoryPrompt(
-        #[CompletionProvider(providerClass: CompletionProviderFixture::class)]
+        #[CompletionProvider(provider: CompletionProviderFixture::class)]
         string $genre,
         int $lengthWords = 200
     ): array {
diff --git a/tests/Fixtures/Discovery/DiscoverableTemplateHandler.php b/tests/Fixtures/Discovery/DiscoverableTemplateHandler.php
index ee7171f..29917cb 100644
--- a/tests/Fixtures/Discovery/DiscoverableTemplateHandler.php
+++ b/tests/Fixtures/Discovery/DiscoverableTemplateHandler.php
@@ -23,7 +23,7 @@ class DiscoverableTemplateHandler
     )]
     public function getProductDetails(
         string $productId,
-        #[CompletionProvider(providerClass: CompletionProviderFixture::class)]
+        #[CompletionProvider(provider: CompletionProviderFixture::class)]
         string $region
     ): array {
         return [
diff --git a/tests/Fixtures/Discovery/EnhancedCompletionHandler.php b/tests/Fixtures/Discovery/EnhancedCompletionHandler.php
new file mode 100644
index 0000000..00336de
--- /dev/null
+++ b/tests/Fixtures/Discovery/EnhancedCompletionHandler.php
@@ -0,0 +1,50 @@
+<?php
+
+declare(strict_types=1);
+
+namespace PhpMcp\Server\Tests\Fixtures\Discovery;
+
+use PhpMcp\Server\Attributes\McpPrompt;
+use PhpMcp\Server\Attributes\McpResourceTemplate;
+use PhpMcp\Server\Attributes\CompletionProvider;
+use PhpMcp\Server\Tests\Fixtures\Enums\StatusEnum;
+use PhpMcp\Server\Tests\Fixtures\Enums\PriorityEnum;
+
+class EnhancedCompletionHandler
+{
+    /**
+     * Create content with list and enum completion providers.
+     */
+    #[McpPrompt(name: 'content_creator')]
+    public function createContent(
+        #[CompletionProvider(values: ['blog', 'article', 'tutorial', 'guide'])]
+        string $type,
+        #[CompletionProvider(enum: StatusEnum::class)]
+        string $status,
+        #[CompletionProvider(enum: PriorityEnum::class)]
+        string $priority
+    ): array {
+        return [
+            ['role' => 'user', 'content' => "Create a {$type} with status {$status} and priority {$priority}"]
+        ];
+    }
+
+    /**
+     * Resource template with list completion for categories.
+     */
+    #[McpResourceTemplate(
+        uriTemplate: 'content://{category}/{slug}',
+        name: 'content_template'
+    )]
+    public function getContent(
+        #[CompletionProvider(values: ['news', 'blog', 'docs', 'api'])]
+        string $category,
+        string $slug
+    ): array {
+        return [
+            'category' => $category,
+            'slug' => $slug,
+            'url' => "https://example.com/{$category}/{$slug}"
+        ];
+    }
+}
diff --git a/tests/Fixtures/Enums/PriorityEnum.php b/tests/Fixtures/Enums/PriorityEnum.php
new file mode 100644
index 0000000..1145735
--- /dev/null
+++ b/tests/Fixtures/Enums/PriorityEnum.php
@@ -0,0 +1,12 @@
+<?php
+
+declare(strict_types=1);
+
+namespace PhpMcp\Server\Tests\Fixtures\Enums;
+
+enum PriorityEnum: int
+{
+    case LOW = 1;
+    case MEDIUM = 2;
+    case HIGH = 3;
+}
diff --git a/tests/Fixtures/Enums/StatusEnum.php b/tests/Fixtures/Enums/StatusEnum.php
new file mode 100644
index 0000000..8ef1236
--- /dev/null
+++ b/tests/Fixtures/Enums/StatusEnum.php
@@ -0,0 +1,12 @@
+<?php
+
+declare(strict_types=1);
+
+namespace PhpMcp\Server\Tests\Fixtures\Enums;
+
+enum StatusEnum: string
+{
+    case DRAFT = 'draft';
+    case PUBLISHED = 'published';
+    case ARCHIVED = 'archived';
+}
diff --git a/tests/Fixtures/General/PromptHandlerFixture.php b/tests/Fixtures/General/PromptHandlerFixture.php
index 92c0bca..c95a7d4 100644
--- a/tests/Fixtures/General/PromptHandlerFixture.php
+++ b/tests/Fixtures/General/PromptHandlerFixture.php
@@ -103,7 +103,7 @@ public function returnMixedArrayOfPromptMessagesAndRaw(): array
     }
 
     public function promptWithArgumentCompletion(
-        #[CompletionProvider(providerClass: CompletionProviderFixture::class)]
+        #[CompletionProvider(provider: CompletionProviderFixture::class)]
         string $entityName,
         string $action = "describe"
     ): array {
diff --git a/tests/Integration/DiscoveryTest.php b/tests/Integration/DiscoveryTest.php
index 7adf82e..3fad529 100644
--- a/tests/Integration/DiscoveryTest.php
+++ b/tests/Integration/DiscoveryTest.php
@@ -1,10 +1,17 @@
 <?php
 
+use PhpMcp\Server\Defaults\EnumCompletionProvider;
+use PhpMcp\Server\Defaults\ListCompletionProvider;
 use PhpMcp\Server\Elements\RegisteredPrompt;
 use PhpMcp\Server\Elements\RegisteredResource;
 use PhpMcp\Server\Elements\RegisteredResourceTemplate;
 use PhpMcp\Server\Elements\RegisteredTool;
 use PhpMcp\Server\Registry;
+use PhpMcp\Server\Tests\Fixtures\Discovery\DiscoverableToolHandler;
+use PhpMcp\Server\Tests\Fixtures\Discovery\InvocablePromptFixture;
+use PhpMcp\Server\Tests\Fixtures\Discovery\InvocableResourceFixture;
+use PhpMcp\Server\Tests\Fixtures\Discovery\InvocableResourceTemplateFixture;
+use PhpMcp\Server\Tests\Fixtures\Discovery\InvocableToolFixture;
 use PhpMcp\Server\Utils\Discoverer;
 use PhpMcp\Server\Utils\DocBlockParser;
 use PhpMcp\Server\Utils\SchemaGenerator;
@@ -27,7 +34,6 @@
 
     $this->discoverer->discover($this->fixtureBasePath, [$scanDir]);
 
-    // --- Assert Tools ---
     $tools = $this->registry->getTools();
     expect($tools)->toHaveCount(4); // greet_user, repeatAction, InvokableCalculator, hidden_subdir_tool
 
@@ -36,7 +42,7 @@
         ->and($greetUserTool->isManual)->toBeFalse()
         ->and($greetUserTool->schema->name)->toBe('greet_user')
         ->and($greetUserTool->schema->description)->toBe('Greets a user by name.')
-        ->and($greetUserTool->handler)->toBe([\PhpMcp\Server\Tests\Fixtures\Discovery\DiscoverableToolHandler::class, 'greet']);
+        ->and($greetUserTool->handler)->toBe([DiscoverableToolHandler::class, 'greet']);
     expect($greetUserTool->schema->inputSchema['properties'] ?? [])->toHaveKey('name');
 
     $repeatActionTool = $this->registry->getTool('repeatAction');
@@ -49,14 +55,13 @@
     $invokableCalcTool = $this->registry->getTool('InvokableCalculator');
     expect($invokableCalcTool)->toBeInstanceOf(RegisteredTool::class)
         ->and($invokableCalcTool->isManual)->toBeFalse()
-        ->and($invokableCalcTool->handler)->toBe([\PhpMcp\Server\Tests\Fixtures\Discovery\InvocableToolFixture::class, '__invoke']);
+        ->and($invokableCalcTool->handler)->toBe([InvocableToolFixture::class, '__invoke']);
 
     expect($this->registry->getTool('private_tool_should_be_ignored'))->toBeNull();
     expect($this->registry->getTool('protected_tool_should_be_ignored'))->toBeNull();
     expect($this->registry->getTool('static_tool_should_be_ignored'))->toBeNull();
 
 
-    // --- Assert Resources ---
     $resources = $this->registry->getResources();
     expect($resources)->toHaveCount(3); // app_version, ui_settings_discovered, InvocableResourceFixture
 
@@ -69,18 +74,17 @@
     $invokableStatusRes = $this->registry->getResource('invokable://config/status');
     expect($invokableStatusRes)->toBeInstanceOf(RegisteredResource::class)
         ->and($invokableStatusRes->isManual)->toBeFalse()
-        ->and($invokableStatusRes->handler)->toBe([\PhpMcp\Server\Tests\Fixtures\Discovery\InvocableResourceFixture::class, '__invoke']);
+        ->and($invokableStatusRes->handler)->toBe([InvocableResourceFixture::class, '__invoke']);
 
 
-    // --- Assert Prompts ---
     $prompts = $this->registry->getPrompts();
-    expect($prompts)->toHaveCount(3); // creative_story_prompt, simpleQuestionPrompt, InvocablePromptFixture
+    expect($prompts)->toHaveCount(4); // creative_story_prompt, simpleQuestionPrompt, InvocablePromptFixture, content_creator
 
     $storyPrompt = $this->registry->getPrompt('creative_story_prompt');
     expect($storyPrompt)->toBeInstanceOf(RegisteredPrompt::class)
         ->and($storyPrompt->isManual)->toBeFalse()
         ->and($storyPrompt->schema->arguments)->toHaveCount(2) // genre, lengthWords
-        ->and($storyPrompt->getCompletionProvider('genre'))->toBe(CompletionProviderFixture::class);
+        ->and($storyPrompt->completionProviders['genre'])->toBe(CompletionProviderFixture::class);
 
     $simplePrompt = $this->registry->getPrompt('simpleQuestionPrompt'); // Inferred name
     expect($simplePrompt)->toBeInstanceOf(RegisteredPrompt::class)
@@ -89,24 +93,27 @@
     $invokableGreeter = $this->registry->getPrompt('InvokableGreeterPrompt');
     expect($invokableGreeter)->toBeInstanceOf(RegisteredPrompt::class)
         ->and($invokableGreeter->isManual)->toBeFalse()
-        ->and($invokableGreeter->handler)->toBe([\PhpMcp\Server\Tests\Fixtures\Discovery\InvocablePromptFixture::class, '__invoke']);
+        ->and($invokableGreeter->handler)->toBe([InvocablePromptFixture::class, '__invoke']);
 
+    $contentCreatorPrompt = $this->registry->getPrompt('content_creator');
+    expect($contentCreatorPrompt)->toBeInstanceOf(RegisteredPrompt::class)
+        ->and($contentCreatorPrompt->isManual)->toBeFalse()
+        ->and($contentCreatorPrompt->completionProviders)->toHaveCount(3);
 
-    // --- Assert Resource Templates ---
     $templates = $this->registry->getResourceTemplates();
-    expect($templates)->toHaveCount(3); // product_details_template, getFileContent, InvocableResourceTemplateFixture
+    expect($templates)->toHaveCount(4); // product_details_template, getFileContent, InvocableResourceTemplateFixture, content_template
 
     $productTemplate = $this->registry->getResourceTemplate('product://{region}/details/{productId}');
     expect($productTemplate)->toBeInstanceOf(RegisteredResourceTemplate::class)
         ->and($productTemplate->isManual)->toBeFalse()
         ->and($productTemplate->schema->name)->toBe('product_details_template')
-        ->and($productTemplate->getCompletionProvider('region'))->toBe(CompletionProviderFixture::class);
+        ->and($productTemplate->completionProviders['region'])->toBe(CompletionProviderFixture::class);
     expect($productTemplate->getVariableNames())->toEqualCanonicalizing(['region', 'productId']);
 
     $invokableUserTemplate = $this->registry->getResourceTemplate('invokable://user-profile/{userId}');
     expect($invokableUserTemplate)->toBeInstanceOf(RegisteredResourceTemplate::class)
         ->and($invokableUserTemplate->isManual)->toBeFalse()
-        ->and($invokableUserTemplate->handler)->toBe([\PhpMcp\Server\Tests\Fixtures\Discovery\InvocableResourceTemplateFixture::class, '__invoke']);
+        ->and($invokableUserTemplate->handler)->toBe([InvocableResourceTemplateFixture::class, '__invoke']);
 });
 
 it('does not discover elements from excluded directories', function () {
@@ -140,3 +147,28 @@
     expect($invokableCalc->schema->name)->toBe('InvokableCalculator');
     expect($invokableCalc->schema->description)->toBe('An invokable calculator tool.');
 });
+
+it('discovers enhanced completion providers with values and enum attributes', function () {
+    $this->discoverer->discover($this->fixtureBasePath, ['Discovery']);
+
+    $contentPrompt = $this->registry->getPrompt('content_creator');
+    expect($contentPrompt)->toBeInstanceOf(RegisteredPrompt::class);
+
+    expect($contentPrompt->completionProviders)->toHaveCount(3);
+
+    $typeProvider = $contentPrompt->completionProviders['type'];
+    expect($typeProvider)->toBeInstanceOf(ListCompletionProvider::class);
+
+    $statusProvider = $contentPrompt->completionProviders['status'];
+    expect($statusProvider)->toBeInstanceOf(EnumCompletionProvider::class);
+
+    $priorityProvider = $contentPrompt->completionProviders['priority'];
+    expect($priorityProvider)->toBeInstanceOf(EnumCompletionProvider::class);
+
+    $contentTemplate = $this->registry->getResourceTemplate('content://{category}/{slug}');
+    expect($contentTemplate)->toBeInstanceOf(RegisteredResourceTemplate::class);
+    expect($contentTemplate->completionProviders)->toHaveCount(1);
+
+    $categoryProvider = $contentTemplate->completionProviders['category'];
+    expect($categoryProvider)->toBeInstanceOf(ListCompletionProvider::class);
+});
diff --git a/tests/Unit/Attributes/CompletionProviderTest.php b/tests/Unit/Attributes/CompletionProviderTest.php
new file mode 100644
index 0000000..cbe1c8a
--- /dev/null
+++ b/tests/Unit/Attributes/CompletionProviderTest.php
@@ -0,0 +1,70 @@
+<?php
+
+declare(strict_types=1);
+
+namespace PhpMcp\Server\Tests\Unit\Attributes;
+
+use PhpMcp\Server\Attributes\CompletionProvider;
+use PhpMcp\Server\Tests\Fixtures\General\CompletionProviderFixture;
+use PhpMcp\Server\Defaults\ListCompletionProvider;
+use PhpMcp\Server\Defaults\EnumCompletionProvider;
+
+enum TestEnum: string
+{
+    case DRAFT = 'draft';
+    case PUBLISHED = 'published';
+    case ARCHIVED = 'archived';
+}
+
+it('can be constructed with provider class', function () {
+    $attribute = new CompletionProvider(provider: CompletionProviderFixture::class);
+
+    expect($attribute->provider)->toBe(CompletionProviderFixture::class);
+    expect($attribute->values)->toBeNull();
+    expect($attribute->enum)->toBeNull();
+});
+
+it('can be constructed with provider instance', function () {
+    $instance = new CompletionProviderFixture();
+    $attribute = new CompletionProvider(provider: $instance);
+
+    expect($attribute->provider)->toBe($instance);
+    expect($attribute->values)->toBeNull();
+    expect($attribute->enum)->toBeNull();
+});
+
+it('can be constructed with values array', function () {
+    $values = ['draft', 'published', 'archived'];
+    $attribute = new CompletionProvider(values: $values);
+
+    expect($attribute->provider)->toBeNull();
+    expect($attribute->values)->toBe($values);
+    expect($attribute->enum)->toBeNull();
+});
+
+it('can be constructed with enum class', function () {
+    $attribute = new CompletionProvider(enum: TestEnum::class);
+
+    expect($attribute->provider)->toBeNull();
+    expect($attribute->values)->toBeNull();
+    expect($attribute->enum)->toBe(TestEnum::class);
+});
+
+it('throws exception when no parameters provided', function () {
+    new CompletionProvider();
+})->throws(\InvalidArgumentException::class, 'Only one of provider, values, or enum can be set');
+
+it('throws exception when multiple parameters provided', function () {
+    new CompletionProvider(
+        provider: CompletionProviderFixture::class,
+        values: ['test']
+    );
+})->throws(\InvalidArgumentException::class, 'Only one of provider, values, or enum can be set');
+
+it('throws exception when all parameters provided', function () {
+    new CompletionProvider(
+        provider: CompletionProviderFixture::class,
+        values: ['test'],
+        enum: TestEnum::class
+    );
+})->throws(\InvalidArgumentException::class, 'Only one of provider, values, or enum can be set');
diff --git a/tests/Unit/Defaults/EnumCompletionProviderTest.php b/tests/Unit/Defaults/EnumCompletionProviderTest.php
new file mode 100644
index 0000000..3caf400
--- /dev/null
+++ b/tests/Unit/Defaults/EnumCompletionProviderTest.php
@@ -0,0 +1,90 @@
+<?php
+
+declare(strict_types=1);
+
+namespace PhpMcp\Server\Tests\Unit\Defaults;
+
+use PhpMcp\Server\Defaults\EnumCompletionProvider;
+use PhpMcp\Server\Contracts\SessionInterface;
+use Mockery;
+
+enum StringEnum: string
+{
+    case DRAFT = 'draft';
+    case PUBLISHED = 'published';
+    case ARCHIVED = 'archived';
+}
+
+enum IntEnum: int
+{
+    case LOW = 1;
+    case MEDIUM = 2;
+    case HIGH = 3;
+}
+
+enum UnitEnum
+{
+    case ALPHA;
+    case BETA;
+    case GAMMA;
+}
+
+beforeEach(function () {
+    $this->session = Mockery::mock(SessionInterface::class);
+});
+
+it('creates provider from string-backed enum', function () {
+    $provider = new EnumCompletionProvider(StringEnum::class);
+
+    $result = $provider->getCompletions('', $this->session);
+
+    expect($result)->toBe(['draft', 'published', 'archived']);
+});
+
+it('creates provider from int-backed enum using names', function () {
+    $provider = new EnumCompletionProvider(IntEnum::class);
+
+    $result = $provider->getCompletions('', $this->session);
+
+    expect($result)->toBe(['LOW', 'MEDIUM', 'HIGH']);
+});
+
+it('creates provider from unit enum using names', function () {
+    $provider = new EnumCompletionProvider(UnitEnum::class);
+
+    $result = $provider->getCompletions('', $this->session);
+
+    expect($result)->toBe(['ALPHA', 'BETA', 'GAMMA']);
+});
+
+it('filters string enum values by prefix', function () {
+    $provider = new EnumCompletionProvider(StringEnum::class);
+
+    $result = $provider->getCompletions('ar', $this->session);
+
+    expect($result)->toEqual(['archived']);
+});
+
+it('filters unit enum values by prefix', function () {
+    $provider = new EnumCompletionProvider(UnitEnum::class);
+
+    $result = $provider->getCompletions('A', $this->session);
+
+    expect($result)->toBe(['ALPHA']);
+});
+
+it('returns empty array when no values match prefix', function () {
+    $provider = new EnumCompletionProvider(StringEnum::class);
+
+    $result = $provider->getCompletions('xyz', $this->session);
+
+    expect($result)->toBe([]);
+});
+
+it('throws exception for non-enum class', function () {
+    new EnumCompletionProvider(\stdClass::class);
+})->throws(\InvalidArgumentException::class, 'Class stdClass is not an enum');
+
+it('throws exception for non-existent class', function () {
+    new EnumCompletionProvider('NonExistentClass');
+})->throws(\InvalidArgumentException::class, 'Class NonExistentClass is not an enum');
diff --git a/tests/Unit/Defaults/ListCompletionProviderTest.php b/tests/Unit/Defaults/ListCompletionProviderTest.php
new file mode 100644
index 0000000..741d0b8
--- /dev/null
+++ b/tests/Unit/Defaults/ListCompletionProviderTest.php
@@ -0,0 +1,75 @@
+<?php
+
+declare(strict_types=1);
+
+namespace PhpMcp\Server\Tests\Unit\Defaults;
+
+use PhpMcp\Server\Defaults\ListCompletionProvider;
+use PhpMcp\Server\Contracts\SessionInterface;
+use Mockery;
+
+beforeEach(function () {
+    $this->session = Mockery::mock(SessionInterface::class);
+});
+
+it('returns all values when current value is empty', function () {
+    $values = ['apple', 'banana', 'cherry'];
+    $provider = new ListCompletionProvider($values);
+
+    $result = $provider->getCompletions('', $this->session);
+
+    expect($result)->toBe($values);
+});
+
+it('filters values based on current value prefix', function () {
+    $values = ['apple', 'apricot', 'banana', 'cherry'];
+    $provider = new ListCompletionProvider($values);
+
+    $result = $provider->getCompletions('ap', $this->session);
+
+    expect($result)->toBe(['apple', 'apricot']);
+});
+
+it('returns empty array when no values match', function () {
+    $values = ['apple', 'banana', 'cherry'];
+    $provider = new ListCompletionProvider($values);
+
+    $result = $provider->getCompletions('xyz', $this->session);
+
+    expect($result)->toBe([]);
+});
+
+it('works with single character prefix', function () {
+    $values = ['apple', 'banana', 'cherry'];
+    $provider = new ListCompletionProvider($values);
+
+    $result = $provider->getCompletions('a', $this->session);
+
+    expect($result)->toBe(['apple']);
+});
+
+it('is case sensitive by default', function () {
+    $values = ['Apple', 'apple', 'APPLE'];
+    $provider = new ListCompletionProvider($values);
+
+    $result = $provider->getCompletions('A', $this->session);
+
+    expect($result)->toEqual(['Apple', 'APPLE']);
+});
+
+it('handles empty values array', function () {
+    $provider = new ListCompletionProvider([]);
+
+    $result = $provider->getCompletions('test', $this->session);
+
+    expect($result)->toBe([]);
+});
+
+it('preserves array order', function () {
+    $values = ['zebra', 'apple', 'banana'];
+    $provider = new ListCompletionProvider($values);
+
+    $result = $provider->getCompletions('', $this->session);
+
+    expect($result)->toBe(['zebra', 'apple', 'banana']);
+});
diff --git a/tests/Unit/DispatcherTest.php b/tests/Unit/DispatcherTest.php
index 2c26da0..a6c83ea 100644
--- a/tests/Unit/DispatcherTest.php
+++ b/tests/Unit/DispatcherTest.php
@@ -53,6 +53,7 @@
 use PhpMcp\Schema\ResourceReference;
 use PhpMcp\Server\Protocol;
 use React\EventLoop\Loop;
+use PhpMcp\Server\Tests\Unit\Attributes\TestEnum;
 
 const DISPATCHER_SESSION_ID = 'dispatcher-session-xyz';
 const DISPATCHER_PAGINATION_LIMIT = 3;
@@ -433,10 +434,14 @@
     $providerClass = get_class($mockCompletionProvider);
 
     $promptSchema = PromptSchema::make($promptName, '', [PromptArgument::make($argName)]);
-    $registeredPromptMock = Mockery::mock(RegisteredPrompt::class, [$promptSchema, ['MyPromptHandler', 'get'], false]);
-    $registeredPromptMock->shouldReceive('getCompletionProvider')->with($argName)->andReturn($providerClass);
+    $registeredPrompt = new RegisteredPrompt(
+        schema: $promptSchema,
+        handler: ['MyPromptHandler', 'get'],
+        isManual: false,
+        completionProviders: [$argName => $providerClass]
+    );
 
-    $this->registry->shouldReceive('getPrompt')->with($promptName)->andReturn($registeredPromptMock);
+    $this->registry->shouldReceive('getPrompt')->with($promptName)->andReturn($registeredPrompt);
     $this->container->shouldReceive('get')->with($providerClass)->andReturn($mockCompletionProvider);
     $mockCompletionProvider->shouldReceive('getCompletions')->with($currentValue, $this->session)->andReturn($completions);
 
@@ -458,11 +463,14 @@
     $providerClass = get_class($mockCompletionProvider);
 
     $templateSchema = ResourceTemplateSchema::make($templateUri, 'item-template');
-    $registeredTemplateMock = Mockery::mock(RegisteredResourceTemplate::class, [$templateSchema, ['MyResourceTemplateHandler', 'get'], false]);
-    $registeredTemplateMock->shouldReceive('getVariableNames')->andReturn(['itemId', 'catName']);
-    $registeredTemplateMock->shouldReceive('getCompletionProvider')->with($uriVarName)->andReturn($providerClass);
+    $registeredTemplate = new RegisteredResourceTemplate(
+        schema: $templateSchema,
+        handler: ['MyResourceTemplateHandler', 'get'],
+        isManual: false,
+        completionProviders: [$uriVarName => $providerClass]
+    );
 
-    $this->registry->shouldReceive('getResourceTemplate')->with($templateUri)->andReturn($registeredTemplateMock);
+    $this->registry->shouldReceive('getResourceTemplate')->with($templateUri)->andReturn($registeredTemplate);
     $this->container->shouldReceive('get')->with($providerClass)->andReturn($mockCompletionProvider);
     $mockCompletionProvider->shouldReceive('getCompletions')->with($currentValue, $this->session)->andReturn($completions);
 
@@ -475,15 +483,71 @@
 it('can handle completion complete request and return empty if no provider', function () {
     $promptName = 'no-provider-prompt';
     $promptSchema = PromptSchema::make($promptName, '', [PromptArgument::make('arg')]);
-    $registeredPromptMock = Mockery::mock(RegisteredPrompt::class, [$promptSchema, ['MyPromptHandler', 'get'], false]);
-    $registeredPromptMock->shouldReceive('getCompletionProvider')->andReturn(null);
-    $this->registry->shouldReceive('getPrompt')->with($promptName)->andReturn($registeredPromptMock);
+    $registeredPrompt = new RegisteredPrompt(
+        schema: $promptSchema,
+        handler: ['MyPromptHandler', 'get'],
+        isManual: false,
+        completionProviders: []
+    );
+    $this->registry->shouldReceive('getPrompt')->with($promptName)->andReturn($registeredPrompt);
 
     $request = CompletionCompleteRequest::make(1, PromptReference::make($promptName), ['name' => 'arg', 'value' => '']);
     $result = $this->dispatcher->handleCompletionComplete($request, $this->session);
     expect($result->values)->toBeEmpty();
 });
 
+it('can handle completion complete request with ListCompletionProvider instance', function () {
+    $promptName = 'list-completion-prompt';
+    $argName = 'category';
+    $currentValue = 'bl';
+    $expectedCompletions = ['blog'];
+
+    $listProvider = new \PhpMcp\Server\Defaults\ListCompletionProvider(['blog', 'news', 'docs', 'api']);
+
+    $promptSchema = PromptSchema::make($promptName, '', [PromptArgument::make($argName)]);
+    $registeredPrompt = new RegisteredPrompt(
+        schema: $promptSchema,
+        handler: ['MyPromptHandler', 'get'],
+        isManual: false,
+        completionProviders: [$argName => $listProvider]
+    );
+
+    $this->registry->shouldReceive('getPrompt')->with($promptName)->andReturn($registeredPrompt);
+
+    $request = CompletionCompleteRequest::make(1, PromptReference::make($promptName), ['name' => $argName, 'value' => $currentValue]);
+    $result = $this->dispatcher->handleCompletionComplete($request, $this->session);
+
+    expect($result->values)->toEqual($expectedCompletions);
+    expect($result->total)->toBe(1);
+    expect($result->hasMore)->toBeFalse();
+});
+
+it('can handle completion complete request with EnumCompletionProvider instance', function () {
+    $promptName = 'enum-completion-prompt';
+    $argName = 'status';
+    $currentValue = 'a';
+    $expectedCompletions = ['archived'];
+
+    $enumProvider = new \PhpMcp\Server\Defaults\EnumCompletionProvider(TestEnum::class);
+
+    $promptSchema = PromptSchema::make($promptName, '', [PromptArgument::make($argName)]);
+    $registeredPrompt = new RegisteredPrompt(
+        schema: $promptSchema,
+        handler: ['MyPromptHandler', 'get'],
+        isManual: false,
+        completionProviders: [$argName => $enumProvider]
+    );
+
+    $this->registry->shouldReceive('getPrompt')->with($promptName)->andReturn($registeredPrompt);
+
+    $request = CompletionCompleteRequest::make(1, PromptReference::make($promptName), ['name' => $argName, 'value' => $currentValue]);
+    $result = $this->dispatcher->handleCompletionComplete($request, $this->session);
+
+    expect($result->values)->toEqual($expectedCompletions);
+    expect($result->total)->toBe(1);
+    expect($result->hasMore)->toBeFalse();
+});
+
 
 it('decodeCursor handles null and invalid cursors', function () {
     $method = new \ReflectionMethod(Dispatcher::class, 'decodeCursor');
diff --git a/tests/Unit/Elements/RegisteredPromptTest.php b/tests/Unit/Elements/RegisteredPromptTest.php
index 49abe46..ff59a71 100644
--- a/tests/Unit/Elements/RegisteredPromptTest.php
+++ b/tests/Unit/Elements/RegisteredPromptTest.php
@@ -3,8 +3,7 @@
 namespace PhpMcp\Server\Tests\Unit\Elements;
 
 use Mockery;
-use Mockery\Adapter\Phpunit\MockeryPHPUnitIntegration;
-use PhpMcp\Schema\Prompt as PromptSchema; // Alias
+use PhpMcp\Schema\Prompt as PromptSchema;
 use PhpMcp\Schema\PromptArgument;
 use PhpMcp\Server\Elements\RegisteredPrompt;
 use PhpMcp\Schema\Content\PromptMessage;
@@ -15,10 +14,9 @@
 use PhpMcp\Schema\Content\EmbeddedResource;
 use PhpMcp\Server\Tests\Fixtures\General\PromptHandlerFixture;
 use PhpMcp\Server\Tests\Fixtures\General\CompletionProviderFixture;
+use PhpMcp\Server\Tests\Unit\Attributes\TestEnum;
 use Psr\Container\ContainerInterface;
 
-uses(MockeryPHPUnitIntegration::class);
-
 beforeEach(function () {
     $this->container = Mockery::mock(ContainerInterface::class);
     $this->container->shouldReceive('get')
@@ -46,8 +44,8 @@
     expect($prompt->handler)->toBe([PromptHandlerFixture::class, 'promptWithArgumentCompletion']);
     expect($prompt->isManual)->toBeFalse();
     expect($prompt->completionProviders)->toEqual($providers);
-    expect($prompt->getCompletionProvider('name'))->toBe(CompletionProviderFixture::class);
-    expect($prompt->getCompletionProvider('nonExistentArg'))->toBeNull();
+    expect($prompt->completionProviders['name'])->toBe(CompletionProviderFixture::class);
+    expect($prompt->completionProviders)->not->toHaveKey('nonExistentArg');
 });
 
 it('can be made as a manual registration', function () {
@@ -205,6 +203,7 @@
         [PromptArgument::make('arg1', required: true), PromptArgument::make('arg2', 'description for arg2')]
     );
     $providers = ['arg1' => CompletionProviderFixture::class];
+    $serializedProviders = ['arg1' => serialize(CompletionProviderFixture::class)];
     $original = RegisteredPrompt::make(
         $schema,
         [PromptHandlerFixture::class, 'generateSimpleGreeting'],
@@ -218,7 +217,7 @@
     expect($array['schema']['arguments'])->toHaveCount(2);
     expect($array['handler'])->toBe([PromptHandlerFixture::class, 'generateSimpleGreeting']);
     expect($array['isManual'])->toBeTrue();
-    expect($array['completionProviders'])->toEqual($providers);
+    expect($array['completionProviders'])->toEqual($serializedProviders);
 
     $rehydrated = RegisteredPrompt::fromArray($array);
     expect($rehydrated)->toBeInstanceOf(RegisteredPrompt::class);
@@ -231,3 +230,50 @@
     $badData = ['schema' => ['name' => 'fail']];
     expect(RegisteredPrompt::fromArray($badData))->toBeFalse();
 });
+
+it('can be serialized with ListCompletionProvider instances', function () {
+    $schema = PromptSchema::make(
+        'list-prompt',
+        'Test list completion',
+        [PromptArgument::make('status')]
+    );
+    $listProvider = new \PhpMcp\Server\Defaults\ListCompletionProvider(['draft', 'published', 'archived']);
+    $providers = ['status' => $listProvider];
+
+    $original = RegisteredPrompt::make(
+        $schema,
+        [PromptHandlerFixture::class, 'generateSimpleGreeting'],
+        true,
+        $providers
+    );
+
+    $array = $original->toArray();
+    expect($array['completionProviders']['status'])->toBeString(); // Serialized instance
+
+    $rehydrated = RegisteredPrompt::fromArray($array);
+    expect($rehydrated->completionProviders['status'])->toBeInstanceOf(\PhpMcp\Server\Defaults\ListCompletionProvider::class);
+});
+
+it('can be serialized with EnumCompletionProvider instances', function () {
+    $schema = PromptSchema::make(
+        'enum-prompt',
+        'Test enum completion',
+        [PromptArgument::make('priority')]
+    );
+
+    $enumProvider = new \PhpMcp\Server\Defaults\EnumCompletionProvider(TestEnum::class);
+    $providers = ['priority' => $enumProvider];
+
+    $original = RegisteredPrompt::make(
+        $schema,
+        [PromptHandlerFixture::class, 'generateSimpleGreeting'],
+        true,
+        $providers
+    );
+
+    $array = $original->toArray();
+    expect($array['completionProviders']['priority'])->toBeString(); // Serialized instance
+
+    $rehydrated = RegisteredPrompt::fromArray($array);
+    expect($rehydrated->completionProviders['priority'])->toBeInstanceOf(\PhpMcp\Server\Defaults\EnumCompletionProvider::class);
+});
diff --git a/tests/Unit/Elements/RegisteredResourceTemplateTest.php b/tests/Unit/Elements/RegisteredResourceTemplateTest.php
index 758b5e7..ce3dd5e 100644
--- a/tests/Unit/Elements/RegisteredResourceTemplateTest.php
+++ b/tests/Unit/Elements/RegisteredResourceTemplateTest.php
@@ -3,7 +3,6 @@
 namespace PhpMcp\Server\Tests\Unit\Elements;
 
 use Mockery;
-use Mockery\Adapter\Phpunit\MockeryPHPUnitIntegration;
 use PhpMcp\Schema\ResourceTemplate;
 use PhpMcp\Server\Elements\RegisteredResourceTemplate;
 use PhpMcp\Schema\Content\TextResourceContents;
@@ -12,8 +11,6 @@
 use Psr\Container\ContainerInterface;
 use PhpMcp\Schema\Annotations;
 
-uses(MockeryPHPUnitIntegration::class);
-
 beforeEach(function () {
     $this->container = Mockery::mock(ContainerInterface::class);
     $this->handlerInstance = new ResourceHandlerFixture();
@@ -59,9 +56,9 @@
     expect($template->handler)->toBe([ResourceHandlerFixture::class, 'getUserDocument']);
     expect($template->isManual)->toBeFalse();
     expect($template->completionProviders)->toEqual($completionProviders);
-    expect($template->getCompletionProvider('userId'))->toBe(CompletionProviderFixture::class);
-    expect($template->getCompletionProvider('documentId'))->toBe('Another\ProviderClass');
-    expect($template->getCompletionProvider('nonExistentVar'))->toBeNull();
+    expect($template->completionProviders['userId'])->toBe(CompletionProviderFixture::class);
+    expect($template->completionProviders['documentId'])->toBe('Another\ProviderClass');
+    expect($template->completionProviders)->not->toHaveKey('nonExistentVar');
 });
 
 it('can be made as a manual registration', function () {
@@ -185,6 +182,7 @@
     );
 
     $providers = ['type' => CompletionProviderFixture::class];
+    $serializedProviders = ['type' => serialize(CompletionProviderFixture::class)];
 
     $original = RegisteredResourceTemplate::make(
         $schema,
@@ -201,7 +199,7 @@
     expect($array['schema']['annotations']['priority'])->toBe(0.7);
     expect($array['handler'])->toBe([ResourceHandlerFixture::class, 'getUserDocument']);
     expect($array['isManual'])->toBeTrue();
-    expect($array['completionProviders'])->toEqual($providers);
+    expect($array['completionProviders'])->toEqual($serializedProviders);
 
     $rehydrated = RegisteredResourceTemplate::fromArray($array);
     expect($rehydrated)->toBeInstanceOf(RegisteredResourceTemplate::class);
diff --git a/tests/Unit/ServerBuilderTest.php b/tests/Unit/ServerBuilderTest.php
index 69ded02..ab46f62 100644
--- a/tests/Unit/ServerBuilderTest.php
+++ b/tests/Unit/ServerBuilderTest.php
@@ -42,7 +42,7 @@ public function noArgsHandler(): string
 
     public function handlerWithCompletion(
         string $name,
-        #[CompletionProvider(providerClass: SB_DummyCompletionProvider::class)]
+        #[CompletionProvider(provider: SB_DummyCompletionProvider::class)]
         string $uriParam
     ): array {
         return [];
@@ -467,7 +467,56 @@ public function getCompletions(string $currentValue, SessionInterface $session):
     expect($prompt->schema->arguments)->toHaveCount(2);
     expect($prompt->schema->arguments[0]->name)->toBe('name');
     expect($prompt->schema->arguments[1]->name)->toBe('uriParam');
-    expect($prompt->getCompletionProvider('uriParam'))->toBe(SB_DummyCompletionProvider::class);
+    expect($prompt->completionProviders['uriParam'])->toBe(SB_DummyCompletionProvider::class);
+});
+
+// Add test fixtures for enhanced completion providers
+class SB_DummyHandlerWithEnhancedCompletion
+{
+    public function handleWithListCompletion(
+        #[CompletionProvider(values: ['option1', 'option2', 'option3'])]
+        string $choice
+    ): array {
+        return [['role' => 'user', 'content' => "Selected: {$choice}"]];
+    }
+
+    public function handleWithEnumCompletion(
+        #[CompletionProvider(enum: SB_TestEnum::class)]
+        string $status
+    ): array {
+        return [['role' => 'user', 'content' => "Status: {$status}"]];
+    }
+}
+
+enum SB_TestEnum: string
+{
+    case PENDING = 'pending';
+    case ACTIVE = 'active';
+    case INACTIVE = 'inactive';
+}
+
+it('creates ListCompletionProvider for values attribute in manual registration', function () {
+    $handler = [SB_DummyHandlerWithEnhancedCompletion::class, 'handleWithListCompletion'];
+
+    $server = $this->builder
+        ->withServerInfo('Test', '1.0')
+        ->withPrompt($handler, 'listPrompt')
+        ->build();
+
+    $prompt = $server->getRegistry()->getPrompt('listPrompt');
+    expect($prompt->completionProviders['choice'])->toBeInstanceOf(\PhpMcp\Server\Defaults\ListCompletionProvider::class);
+});
+
+it('creates EnumCompletionProvider for enum attribute in manual registration', function () {
+    $handler = [SB_DummyHandlerWithEnhancedCompletion::class, 'handleWithEnumCompletion'];
+
+    $server = $this->builder
+        ->withServerInfo('Test', '1.0')
+        ->withPrompt($handler, 'enumPrompt')
+        ->build();
+
+    $prompt = $server->getRegistry()->getPrompt('enumPrompt');
+    expect($prompt->completionProviders['status'])->toBeInstanceOf(\PhpMcp\Server\Defaults\EnumCompletionProvider::class);
 });
 
 // it('throws DefinitionException if HandlerResolver fails for a manual element', function () {