diff --git a/src/RpcActionAttribute.php b/src/RpcAction.php
similarity index 89%
rename from src/RpcActionAttribute.php
rename to src/RpcAction.php
index ab5e769..c1761dd 100644
--- a/src/RpcActionAttribute.php
+++ b/src/RpcAction.php
@@ -1,7 +1,7 @@
 <?php
-// RpcActionAttribute.php
+// RpcAction.php
 // Created: 2024-08-15
-// Updated: 2024-08-15
+// Updated: 2024-08-16
 
 namespace Aiwass;
 
@@ -13,7 +13,7 @@ use ReflectionObject;
  * Provides base for attributes that mark methods in a class as RPC action handlers.
  */
 #[Attribute(Attribute::TARGET_METHOD | Attribute::IS_REPEATABLE)]
-class RpcActionAttribute {
+class RpcAction {
     /**
      * @param bool $isProcedure true if the action is a procedure, false if query.
      * @param string $name Action name.
@@ -52,7 +52,7 @@ class RpcActionAttribute {
         $methodInfos = $objectInfo->getMethods();
 
         foreach($methodInfos as $methodInfo) {
-            $attrInfos = $methodInfo->getAttributes(RpcActionAttribute::class, ReflectionAttribute::IS_INSTANCEOF);
+            $attrInfos = $methodInfo->getAttributes(RpcAction::class, ReflectionAttribute::IS_INSTANCEOF);
 
             foreach($attrInfos as $attrInfo) {
                 $handlerInfo = $attrInfo->newInstance();
diff --git a/src/RpcActionHandlerTrait.php b/src/RpcActionHandlerTrait.php
index 21d870c..8d27ded 100644
--- a/src/RpcActionHandlerTrait.php
+++ b/src/RpcActionHandlerTrait.php
@@ -1,7 +1,7 @@
 <?php
 // RpcActionHandlerTrait.php
 // Created: 2024-08-15
-// Updated: 2024-08-15
+// Updated: 2024-08-16
 
 namespace Aiwass;
 
@@ -10,7 +10,7 @@ namespace Aiwass;
  * For more advanced use, everything can be use'd separately and RpcActionAttribute::register called manually.
  */
 trait RpcActionHandlerTrait {
-    public function registerRoutes(RpcServer $server): void {
-        RpcActionAttribute::register($server, $this);
+    public function registerRpcActions(RpcServer $server): void {
+        RpcAction::register($server, $this);
     }
 }
diff --git a/src/RpcActionInfo.php b/src/RpcActionInfo.php
index 2ca1198..7af906f 100644
--- a/src/RpcActionInfo.php
+++ b/src/RpcActionInfo.php
@@ -1,12 +1,14 @@
 <?php
 // RpcActionInfo.php
 // Created: 2024-08-13
-// Updated: 2024-08-13
+// Updated: 2024-08-16
 
 namespace Aiwass;
 
 use Closure;
 use InvalidArgumentException;
+use ReflectionFunction;
+use RuntimeException;
 
 /**
  * Provides information about an RPC action.
@@ -55,4 +57,37 @@ final class RpcActionInfo {
     public function getHandler(): Closure {
         return Closure::fromCallable($this->handler);
     }
+
+    /**
+     * Invokes the handler and ensures required args are specified.
+     *
+     * @param array<string, mixed> $args Arguments to invoke the handler with.
+     * @throws RuntimeException If any given data was invalid.
+     * @return mixed Result of the handler
+     */
+    public function invokeHandler(array $args = []): mixed {
+        $handlerInfo = new ReflectionFunction($this->getHandler());
+        if($handlerInfo->isVariadic())
+            throw new RuntimeException('variadic');
+
+        $handlerArgs = [];
+        $handlerParams = $handlerInfo->getParameters();
+        foreach($handlerParams as $paramInfo) {
+            $paramName = $paramInfo->getName();
+            if(!array_key_exists($paramName, $args)) {
+                if($paramInfo->isOptional())
+                    continue;
+
+                if(!$paramInfo->allowsNull())
+                    throw new RuntimeException('required');
+            }
+
+            $handlerArgs[$paramName] = $args[$paramName] ?? null;
+        }
+
+        if(count($handlerArgs) !== count($args))
+            throw new RuntimeException('params');
+
+        return $handlerInfo->invokeArgs($handlerArgs);
+    }
 }
diff --git a/src/RpcProcedureAttribute.php b/src/RpcProcedure.php
similarity index 77%
rename from src/RpcProcedureAttribute.php
rename to src/RpcProcedure.php
index acc32cf..a3990a3 100644
--- a/src/RpcProcedureAttribute.php
+++ b/src/RpcProcedure.php
@@ -1,7 +1,7 @@
 <?php
-// RpcProcedureAttribute.php
+// RpcProcedure.php
 // Created: 2024-08-15
-// Updated: 2024-08-15
+// Updated: 2024-08-16
 
 namespace Aiwass;
 
@@ -10,7 +10,7 @@ use Attribute;
  * Provides an attribute for marking methods in a class as an RPC Query action.
  */
 #[Attribute(Attribute::TARGET_METHOD | Attribute::IS_REPEATABLE)]
-class RpcProcedureAttribute extends RpcActionAttribute {
+class RpcProcedure extends RpcAction {
     /**
      * @param string $name Action name.
      */
diff --git a/src/RpcQueryAttribute.php b/src/RpcQuery.php
similarity index 78%
rename from src/RpcQueryAttribute.php
rename to src/RpcQuery.php
index 417f612..0771323 100644
--- a/src/RpcQueryAttribute.php
+++ b/src/RpcQuery.php
@@ -1,7 +1,7 @@
 <?php
-// RpcQueryAttribute.php
+// RpcQuery.php
 // Created: 2024-08-15
-// Updated: 2024-08-15
+// Updated: 2024-08-16
 
 namespace Aiwass;
 
@@ -10,7 +10,7 @@ use Attribute;
  * Provides an attribute for marking methods in a class as an RPC Query action.
  */
 #[Attribute(Attribute::TARGET_METHOD | Attribute::IS_REPEATABLE)]
-class RpcQueryAttribute extends RpcActionAttribute {
+class RpcQuery extends RpcAction {
     /**
      * @param string $name Action name.
      */
diff --git a/src/RpcRouteHandler.php b/src/RpcRouteHandler.php
index dac35f4..5e04925 100644
--- a/src/RpcRouteHandler.php
+++ b/src/RpcRouteHandler.php
@@ -1,15 +1,12 @@
 <?php
 // RpcRouteHandler.php
 // Created: 2024-08-13
-// Updated: 2024-08-13
+// Updated: 2024-08-16
 
 namespace Aiwass;
 
 use Exception;
-use ReflectionFunction;
-use ReflectionIntersectionType;
-use ReflectionNamedType;
-use ReflectionUnionType;
+use RuntimeException;
 use Index\Http\{HttpResponseBuilder,HttpRequest};
 use Index\Http\Content\FormContent;
 use Index\Http\Routing\{HttpGet,HttpPost,RouteHandler};
@@ -31,7 +28,7 @@ class RpcRouteHandler extends RouteHandler {
      * @param HttpResponseBuilder $response Response that it being built.
      * @param HttpRequest $request Request that is being handled.
      * @param string $action Name of the action specified in the URL.
-     * @return int|array{error: string, message?: string}|mixed Response to the request.
+     * @return int|string Response to the request.
      */
     #[HttpGet('/_aiwass/([A-Za-z0-9\-_\.:]+)')]
     #[HttpPost('/_aiwass/([A-Za-z0-9\-_\.:]+)')]
@@ -61,49 +58,29 @@ class RpcRouteHandler extends RouteHandler {
         $userToken = (string)$request->getHeaderLine('X-Aiwass-Verify');
         if($userToken === '') {
             $response->setStatusCode(403);
-            return AiwassMsgPack::encode(['error' => 'aiwass:verify', 'message' => 'X-Aiwass-Verify header is missing.']);
+            return AiwassMsgPack::encode(['error' => 'aiwass:verify']);
         }
 
         $actInfo = $this->server->getActionInfo($action);
         if($actInfo === null) {
             $response->setStatusCode(404);
-            return AiwassMsgPack::encode(['error' => 'aiwass:unknown', 'message' => 'No action with that name exists.']);
+            return AiwassMsgPack::encode(['error' => 'aiwass:unknown']);
         }
 
         if($actInfo->isProcedure() !== $expectProcedure) {
             $response->setStatusCode(405);
             $response->setHeader('Allow', $actInfo->isProcedure() ? 'POST' : 'GET');
-            return AiwassMsgPack::encode(['error' => 'aiwass:method', 'message' => 'This action cannot be called using this request method.']);
+            return AiwassMsgPack::encode(['error' => 'aiwass:method']);
         }
 
         if(!$this->server->getVerificationProvider()->verify($userToken, $expectProcedure, $action, $paramString))
-            return AiwassMsgPack::encode(['error' => 'aiwass:verify', 'message' => 'Request token verification failed.']);
+            return AiwassMsgPack::encode(['error' => 'aiwass:verify']);
 
-        $handlerInfo = new ReflectionFunction($actInfo->getHandler());
-        if($handlerInfo->isVariadic())
-            return AiwassMsgPack::encode(['error' => 'aiwass:variadic', 'message' => 'Handler was declared as a variadic method and is thus impossible to be called.']);
-
-        $handlerArgs = [];
-
-        $handlerParams = $handlerInfo->getParameters();
-        foreach($handlerParams as $paramInfo) {
-            $paramName = $paramInfo->getName();
-            if(!array_key_exists($paramName, $params)) {
-                if($paramInfo->isOptional())
-                    continue;
-
-                if(!$paramInfo->allowsNull())
-                    return AiwassMsgPack::encode(['error' => 'aiwass:param:required', 'message' => 'A required parameter is missing.', 'param' => $paramName]);
-            }
-
-            $handlerArgs[$paramName] = $params[$paramName] ?? null;
-        }
-
-        if(count($handlerArgs) !== count($params)) {
+        try {
+            return AiwassMsgPack::encode($actInfo->invokeHandler($params));
+        } catch(RuntimeException $ex) {
             $response->setStatusCode(400);
-            return AiwassMsgPack::encode(['error' => 'aiwass:params', 'message' => 'Unsupported arguments were specified.']);
+            return AiwassMsgPack::encode(['error' => sprintf('aiwass:%s', $ex->getMessage())]);
         }
-
-        return AiwassMsgPack::encode($handlerInfo->invokeArgs($handlerArgs));
     }
 }
diff --git a/tests/AttributesTest.php b/tests/AttributesTest.php
new file mode 100644
index 0000000..2acf87b
--- /dev/null
+++ b/tests/AttributesTest.php
@@ -0,0 +1,100 @@
+<?php
+// AttributesTest.php
+// Created: 2024-08-16
+// Updated: 2024-08-16
+
+declare(strict_types=1);
+
+use RuntimeException;
+use PHPUnit\Framework\TestCase;
+use PHPUnit\Framework\Attributes\{CoversClass,UsesClass};
+use Aiwass\{RpcAction,RpcActionHandler,RpcProcedure,RpcQuery,RpcServer};
+
+#[CoversClass(RpcAction::class)]
+#[CoversClass(RpcActionHandler::class)]
+#[CoversClass(RpcProcedure::class)]
+#[CoversClass(RpcQuery::class)]
+#[UsesClass(RpcServer::class)]
+final class AttributesTest extends TestCase {
+    public function testAttributes(): void {
+        $handler = new class($this) extends RpcActionHandler {
+            private static $that;
+
+            public function __construct(private $self) {
+                self::$that = $self;
+            }
+
+            #[RpcAction(true, 'aiwass:test:proc1')]
+            public function procedureRegisteredUsingActionAttribute() {
+                return 'procedure registered using action attribute';
+            }
+
+            #[RpcAction(false, 'aiwass:test:query1')]
+            public function queryRegisteredUsingActionAttribute(string $beans) {
+                $this->self->assertEquals('it is beans', $beans);
+                return 'query registered using action attribute';
+            }
+
+            #[RpcQuery('aiwass:test:query2')]
+            public static function staticQueryRegisteredUsingQueryAttribute(string $required, string $optional = 'the') {
+                self::$that->assertEquals('internet', $required);
+                self::$that->assertEquals('the', $optional);
+                return 'static query registered using query attribute';
+            }
+
+            #[RpcProcedure('aiwass:test:proc2')]
+            public function dynamicProcedureRegisteredUsingProcedureAttribute(string $optional = 'meow') {
+                $this->self->assertEquals('meow', $optional);
+                return 'dynamic procedure registered using procedure attribute';
+            }
+
+            #[RpcQuery('aiwass:test:query3')]
+            #[RpcProcedure('aiwass:test:proc3')]
+            public function multiple() {
+                return 'a dynamic method registered as both a query and a procedure';
+            }
+
+            public function hasNoAttr() {
+                return 'not an action handler';
+            }
+        };
+
+        $server = RpcServer::createHmac(fn() => 'test');
+        $server->register($handler);
+
+        $this->assertNull($server->getActionInfo('aiwass:none'));
+
+        $proc1 = $server->getActionInfo('aiwass:test:proc1');
+        $this->assertTrue($proc1->isProcedure());
+        $this->assertEquals('aiwass:test:proc1', $proc1->getName());
+        $this->assertEquals('procedure registered using action attribute', $proc1->invokeHandler());
+
+        $proc2 = $server->getActionInfo('aiwass:test:proc2');
+        $this->assertTrue($proc2->isProcedure());
+        $this->assertEquals('aiwass:test:proc2', $proc2->getName());
+        $this->assertEquals('dynamic procedure registered using procedure attribute', $proc2->invokeHandler());
+
+        $query1 = $server->getActionInfo('aiwass:test:query1');
+        $this->assertFalse($query1->isProcedure());
+        $this->assertEquals('aiwass:test:query1', $query1->getName());
+        $this->assertEquals('query registered using action attribute', $query1->invokeHandler(['beans' => 'it is beans']));
+
+        $query2 = $server->getActionInfo('aiwass:test:query2');
+        $this->assertFalse($query2->isProcedure());
+        $this->assertEquals('aiwass:test:query2', $query2->getName());
+        $this->assertEquals('static query registered using query attribute', $query2->invokeHandler(['required' => 'internet']));
+
+        $query3 = $server->getActionInfo('aiwass:test:query3');
+        $proc3 = $server->getActionInfo('aiwass:test:proc3');
+        $this->assertFalse($query3->isProcedure());
+        $this->asserttrue($proc3->isProcedure());
+        $this->assertEquals('aiwass:test:query3', $query3->getName());
+        $this->assertEquals('aiwass:test:proc3', $proc3->getName());
+        $this->assertEquals($query3->getHandler(), $proc3->getHandler());
+        $this->assertEquals('a dynamic method registered as both a query and a procedure', $query3->invokeHandler());
+        $this->assertEquals('a dynamic method registered as both a query and a procedure', $proc3->invokeHandler());
+
+        $this->expectException(RuntimeException::class);
+        $query1->invokeHandler(['notbeans' => 'it is not beans']);
+    }
+}