[QA] Raise PHPStan to level 8

examples/client/stdio_elicitation.php

@@ -43,6 +43,10 @@ public function __invoke(ElicitRequest $request): ElicitResult
     {
         echo "\n[ELICIT] {$request->message}\n";
 
+        if (null === $request->requestedSchema) {
+            return new ElicitResult(ElicitAction::Decline);
+        }
+
         $content = [];
         foreach ($request->requestedSchema->properties as $name => $definition) {
             $default = $this->defaultFor($definition);
@@ -78,7 +82,7 @@ private function defaultFor(object $definition): mixed
 
     private function labelFor(AbstractSchemaDefinition $definition): string
     {
-        return $definition->title;
+        return $definition->title ?? '';
     }
 
     private function cast(object $definition, string $input): mixed

examples/server/bootstrap.php

@@ -51,7 +51,7 @@ function transport(): TransportInterface
 
 function shutdown(ResponseInterface|int $result): never
 {
-    if ('cli' === \PHP_SAPI) {
+    if (is_int($result)) {
         exit($result);
     }
 

examples/server/mcp-apps/WeatherApp.php

@@ -32,10 +32,15 @@ public function getWeatherApp(): TextResourceContents
             prefersBorder: true,
         );
 
+        $html = file_get_contents(__DIR__.'/weather-app.html');
+        if (false === $html) {
+            throw new \RuntimeException('Could not read the weather app template.');
+        }
+
         return new TextResourceContents(
             uri: 'ui://weather-app',
             mimeType: McpApps::MIME_TYPE,
-            text: file_get_contents(__DIR__.'/weather-app.html'),
+            text: $html,
             meta: ['ui' => $contentMeta],
         );
     }

examples/server/oauth-microsoft/McpElements.php

@@ -106,7 +106,7 @@ public function listEmails(int $count = 5): array
                 'id' => 'msg_'.uniqid(),
                 'subject' => "Sample Email #{$i}",
                 'from' => "sender{$i}@example.com",
-                'receivedDateTime' => date('c', strtotime("-{$i} hours")),
+                'receivedDateTime' => date('c', strtotime("-{$i} hours") ?: time()),
             ], range(1, $count)),
         ];
     }

phpstan.dist.neon

@@ -2,7 +2,7 @@ includes:
     - phpstan-baseline.neon
 
 parameters:
-    level: 6
+    level: 8
     paths:
         - examples/
         - src/

src/Capability/Attribute/CompletionProvider.php

@@ -21,9 +21,11 @@
 class CompletionProvider
 {
     /**
-     * @param class-string<ProviderInterface>|ProviderInterface|null $provider if a class-string, it will be resolved
-     *                                                                         from the container at the point of use
-     * @param ?array<int, int|float|string>                          $values   a list of values to use for completion
+     * @param class-string<ProviderInterface>|null                   $providerClass a provider class to resolve from the container at the point of use
+     * @param class-string<ProviderInterface>|ProviderInterface|null $provider      if a class-string, it will be resolved
+     *                                                                              from the container at the point of use
+     * @param ?array<int, int|float|string>                          $values        a list of values to use for completion
+     * @param class-string|null                                      $enum          an enum class whose cases are used for completion
      */
     public function __construct(
         public ?string $providerClass = null,

src/Capability/Attribute/Schema.php

@@ -29,10 +29,10 @@
  *     minLength?: int,
  *     maxLength?: int,
  *     pattern?: string,
- *     minimum?: int,
- *     maximum?: int,
- *     exclusiveMinimum?: int,
- *     exclusiveMaximum?: int,
+ *     minimum?: int|float,
+ *     maximum?: int|float,
+ *     exclusiveMinimum?: bool,
+ *     exclusiveMaximum?: bool,
  *     multipleOf?: int|float,
  *     items?: array<string, mixed>,
  *     minItems?: int,

src/Capability/Completion/ListCompletionProvider.php

@@ -17,11 +17,16 @@
 class ListCompletionProvider implements ProviderInterface
 {
     /**
-     * @param string[] $values
+     * @var string[]
      */
-    public function __construct(
-        private array $values,
-    ) {
+    private array $values;
+
+    /**
+     * @param array<int|float|string> $values
+     */
+    public function __construct(array $values)
+    {
+        $this->values = array_values(array_map(strval(...), $values));
     }
 
     public function getCompletions(string $currentValue): array

src/Capability/Discovery/Discoverer.php

@@ -49,10 +49,13 @@
  */
 final class Discoverer implements DiscovererInterface
 {
+    private readonly DocBlockParser $docBlockParser;
+    private readonly SchemaGeneratorInterface $schemaGenerator;
+
     public function __construct(
         private readonly LoggerInterface $logger = new NullLogger(),
-        private ?DocBlockParser $docBlockParser = null,
-        private ?SchemaGeneratorInterface $schemaGenerator = null,
+        ?DocBlockParser $docBlockParser = null,
+        ?SchemaGeneratorInterface $schemaGenerator = null,
     ) {
         if (!class_exists(Finder::class)) {
             throw new RuntimeException('File-based discovery requires symfony/finder. Run: composer require symfony/finder');
@@ -223,76 +226,65 @@ private function processMethod(\ReflectionMethod $method, array &$discoveredCoun
         try {
             $instance = $attribute->newInstance();
 
-            switch ($attributeClassName) {
-                case McpTool::class:
-                    $name = ElementMetadataResolver::resolveName($method, $instance->name);
-                    $description = ElementMetadataResolver::resolveDescription($method, $instance->description, $this->docBlockParser);
-                    $inputSchema = $this->schemaGenerator->generate($method);
-                    $outputSchema = $this->schemaGenerator->generateOutputSchema($method);
-                    $tool = new Tool(
-                        name: $name,
-                        title: $instance->title,
-                        inputSchema: $inputSchema,
-                        description: $description,
-                        annotations: $instance->annotations,
-                        icons: $instance->icons,
-                        meta: $instance->meta,
-                        outputSchema: $outputSchema,
-                    );
-                    $tools[$name] = new ToolReference($tool, [$className, $methodName]);
-                    ++$discoveredCount['tools'];
-                    break;
-
-                case McpResource::class:
-                    $name = ElementMetadataResolver::resolveName($method, $instance->name);
-                    $description = ElementMetadataResolver::resolveDescription($method, $instance->description, $this->docBlockParser);
-                    $resource = new ResourceDefinition(
-                        $instance->uri,
-                        $name,
-                        $instance->title,
-                        $description,
-                        $instance->mimeType,
-                        $instance->annotations,
-                        $instance->size,
-                        $instance->icons,
-                        $instance->meta,
-                    );
-                    $resources[$instance->uri] = new ResourceReference($resource, [$className, $methodName]);
-
-                    ++$discoveredCount['resources'];
-                    break;
-
-                case McpPrompt::class:
-                    $docBlock = $this->docBlockParser->parseDocBlock($method->getDocComment() ?? null);
-                    $name = ElementMetadataResolver::resolveName($method, $instance->name);
-                    $description = ElementMetadataResolver::resolveDescription($method, $instance->description, $this->docBlockParser);
-                    $arguments = [];
-                    $paramTags = $this->docBlockParser->getParamTags($docBlock);
-                    foreach ($method->getParameters() as $param) {
-                        $reflectionType = $param->getType();
-                        if ($reflectionType instanceof \ReflectionNamedType && !$reflectionType->isBuiltin()) {
-                            continue;
-                        }
-                        $paramTag = $paramTags['$'.$param->getName()] ?? null;
-                        $arguments[] = new PromptArgument($param->getName(), $paramTag ? trim((string) $paramTag->getDescription()) : null, !$param->isOptional() && !$param->isDefaultValueAvailable());
+            if ($instance instanceof McpTool) {
+                $name = ElementMetadataResolver::resolveName($method, $instance->name);
+                $description = ElementMetadataResolver::resolveDescription($method, $instance->description, $this->docBlockParser);
+                $inputSchema = $this->schemaGenerator->generate($method);
+                $outputSchema = $this->schemaGenerator->generateOutputSchema($method);
+                $tool = new Tool(
+                    name: $name,
+                    title: $instance->title,
+                    inputSchema: $inputSchema,
+                    description: $description,
+                    annotations: $instance->annotations,
+                    icons: $instance->icons,
+                    meta: $instance->meta,
+                    outputSchema: $outputSchema,
+                );
+                $tools[$name] = new ToolReference($tool, [$className, $methodName]);
+                ++$discoveredCount['tools'];
+            } elseif ($instance instanceof McpResource) {
+                $name = ElementMetadataResolver::resolveName($method, $instance->name);
+                $description = ElementMetadataResolver::resolveDescription($method, $instance->description, $this->docBlockParser);
+                $resource = new ResourceDefinition(
+                    $instance->uri,
+                    $name,
+                    $instance->title,
+                    $description,
+                    $instance->mimeType,
+                    $instance->annotations,
+                    $instance->size,
+                    $instance->icons,
+                    $instance->meta,
+                );
+                $resources[$instance->uri] = new ResourceReference($resource, [$className, $methodName]);
+
+                ++$discoveredCount['resources'];
+            } elseif ($instance instanceof McpPrompt) {
+                $docBlock = $this->docBlockParser->parseDocBlock($method->getDocComment() ?? null);
+                $name = ElementMetadataResolver::resolveName($method, $instance->name);
+                $description = ElementMetadataResolver::resolveDescription($method, $instance->description, $this->docBlockParser);
+                $arguments = [];
+                $paramTags = $this->docBlockParser->getParamTags($docBlock);
+                foreach ($method->getParameters() as $param) {
+                    $reflectionType = $param->getType();
+                    if ($reflectionType instanceof \ReflectionNamedType && !$reflectionType->isBuiltin()) {
+                        continue;
                     }
-                    $prompt = new Prompt($name, $instance->title, $description, $arguments, $instance->icons, $instance->meta);
-                    $completionProviders = $this->getCompletionProviders($method);
-                    $prompts[$name] = new PromptReference($prompt, [$className, $methodName], $completionProviders);
-                    ++$discoveredCount['prompts'];
-                    break;
-
-                case McpResourceTemplate::class:
-                    $name = ElementMetadataResolver::resolveName($method, $instance->name);
-                    $description = ElementMetadataResolver::resolveDescription($method, $instance->description, $this->docBlockParser);
-                    $mimeType = $instance->mimeType;
-                    $annotations = $instance->annotations;
-                    $meta = $instance->meta ?? null;
-                    $resourceTemplate = new ResourceTemplate($instance->uriTemplate, $name, $instance->title, $description, $mimeType, $annotations, $meta);
-                    $completionProviders = $this->getCompletionProviders($method);
-                    $resourceTemplates[$instance->uriTemplate] = new ResourceTemplateReference($resourceTemplate, [$className, $methodName], $completionProviders);
-                    ++$discoveredCount['resourceTemplates'];
-                    break;
+                    $paramTag = $paramTags['$'.$param->getName()] ?? null;
+                    $arguments[] = new PromptArgument($param->getName(), $paramTag ? trim((string) $paramTag->getDescription()) : null, !$param->isOptional() && !$param->isDefaultValueAvailable());
+                }
+                $prompt = new Prompt($name, $instance->title, $description, $arguments, $instance->icons, $instance->meta);
+                $completionProviders = $this->getCompletionProviders($method);
+                $prompts[$name] = new PromptReference($prompt, [$className, $methodName], $completionProviders);
+                ++$discoveredCount['prompts'];
+            } elseif ($instance instanceof McpResourceTemplate) {
+                $name = ElementMetadataResolver::resolveName($method, $instance->name);
+                $description = ElementMetadataResolver::resolveDescription($method, $instance->description, $this->docBlockParser);
+                $resourceTemplate = new ResourceTemplate($instance->uriTemplate, $name, $instance->title, $description, $instance->mimeType, $instance->annotations, $instance->meta);
+                $completionProviders = $this->getCompletionProviders($method);
+                $resourceTemplates[$instance->uriTemplate] = new ResourceTemplateReference($resourceTemplate, [$className, $methodName], $completionProviders);
+                ++$discoveredCount['resourceTemplates'];
             }
         } catch (ExceptionInterface $e) {
             $this->logger->error("Failed to process MCP attribute on {$className}::{$methodName}", [
@@ -308,7 +300,7 @@ private function processMethod(\ReflectionMethod $method, array &$discoveredCoun
     }
 
     /**
-     * @return array<string, string|ProviderInterface>
+     * @return array<string, class-string<ProviderInterface>|ProviderInterface>
      */
     private function getCompletionProviders(\ReflectionMethod $reflectionMethod): array
     {
@@ -326,7 +318,7 @@ private function getCompletionProviders(\ReflectionMethod $reflectionMethod): ar
                 if ($attributeInstance->provider) {
                     $completionProviders[$param->getName()] = $attributeInstance->provider;
                 } elseif ($attributeInstance->providerClass) {
-                    $completionProviders[$param->getName()] = $attributeInstance->provider;
+                    $completionProviders[$param->getName()] = $attributeInstance->providerClass;
                 } elseif ($attributeInstance->values) {
                     $completionProviders[$param->getName()] = new ListCompletionProvider($attributeInstance->values);
                 } elseif ($attributeInstance->enum) {
@@ -433,17 +425,13 @@ private function getClassFromFile(SplFileInfo $file): ?string
         }
 
         foreach ($potentialClasses as $potentialClass) {
-            if (class_exists($potentialClass, true)) {
+            if (class_exists($potentialClass, true) || interface_exists($potentialClass, true) || trait_exists($potentialClass, true)) {
                 return $potentialClass;
             }
         }
 
         if (!empty($potentialClasses)) {
-            if (!class_exists($potentialClasses[0], false)) {
-                $this->logger->debug('getClassFromFile returning potential non-class type. Are you sure this class has been autoloaded?', ['file' => $file->getPathname(), 'type' => $potentialClasses[0]]);
-            }
-
-            return $potentialClasses[0];
+            $this->logger->debug('getClassFromFile found no loadable type. Are you sure this class has been autoloaded?', ['file' => $file->getPathname(), 'type' => $potentialClasses[0]]);
         }
 
         return null;

src/Capability/Discovery/SchemaGenerator.php

@@ -49,12 +49,6 @@
  *     enum?: array<int, int|float|string|null>,
  *     items?: array<string, mixed>,
  * }
- * @phpstan-type VariadicParameterSchema array{
- *     type: 'array',
- *     items?: array<string, mixed>,
- *     description?: string,
- *     parameter_schema?: array<string, mixed>
- * }
  *
  * @author Kyrian Obikwelu <koshnawaza@gmail.com>
  */
@@ -328,7 +322,7 @@ private function buildInferredParameterSchema(array $paramInfo): array
      *
      * @param ParameterInfo $paramInfo
      *
-     * @return VariadicParameterSchema
+     * @return array<string, mixed>
      */
     private function buildVariadicParameterSchema(array $paramInfo): array
     {
@@ -536,7 +530,8 @@ private function parseParametersInfo(\ReflectionMethod|\ReflectionFunction $refl
 
             $paramName = $rp->getName();
             if (\in_array(strtolower($paramName), ['_session', '_request'], true)) {
-                throw new InvalidArgumentException(\sprintf('Handler method "%s::%s" has parameter named "%s" which is not allowed. Please change the name of that parameter.', $reflection->class, $reflection->name, $paramName));
+                $handlerName = $reflection instanceof \ReflectionMethod ? $reflection->class.'::'.$reflection->name : $reflection->name;
+                throw new InvalidArgumentException(\sprintf('Handler "%s" has parameter named "%s" which is not allowed. Please change the name of that parameter.', $handlerName, $paramName));
             }
             $paramTag = $paramTags['$'.$paramName] ?? null;
 
@@ -693,8 +688,10 @@ private function getTypeStringFromReflection(?\ReflectionType $type, bool $nativ
         // Remove leading backslash from class names, but handle built-ins like 'int' or unions like 'int|string'
         if (str_contains($typeString, '\\')) {
             $parts = preg_split('/([|&])/', $typeString, -1, \PREG_SPLIT_DELIM_CAPTURE);
-            $processedParts = array_map(static fn ($part) => str_starts_with($part, '\\') ? ltrim($part, '\\') : $part, $parts);
-            $typeString = implode('', $processedParts);
+            if (false !== $parts) {
+                $processedParts = array_map(static fn ($part) => str_starts_with($part, '\\') ? ltrim($part, '\\') : $part, $parts);
+                $typeString = implode('', $processedParts);
+            }
         }
 
         return $typeString ?: 'mixed';

src/Capability/Discovery/SchemaGeneratorInterface.php

@@ -11,9 +11,13 @@
 
 namespace Mcp\Capability\Discovery;
 
+use Mcp\Schema\Tool;
+
 /**
  * Provides JSON Schema generation for reflected elements.
  *
+ * @phpstan-import-type ToolInputSchema from Tool
+ *
  * @author Antoine Bluchet <soyuka@gmail.com>
  */
 interface SchemaGeneratorInterface
@@ -24,11 +28,7 @@ interface SchemaGeneratorInterface
      * The returned schema must be a valid JSON Schema object (type: 'object')
      * with properties corresponding to a tool's parameters.
      *
-     * @return array{
-     *     type: 'object',
-     *     properties: array<string, mixed>|object,
-     *     required?: string[]
-     * }
+     * @return ToolInputSchema
      */
     public function generate(\Reflector $reflection): array;