diff --git a/app/Http/Controllers/Oai/RequestController.php b/app/Http/Controllers/Oai/RequestController.php
index 7f34cdd..f916f03 100644
--- a/app/Http/Controllers/Oai/RequestController.php
+++ b/app/Http/Controllers/Oai/RequestController.php
@@ -145,9 +145,10 @@ class RequestController extends Controller
                 $this->handleIllegalVerb();
             }
         } else {
-            $oaiRequest['verb'] = 'Identify';
-            $this->proc->setParameter('', 'oai_verb', $oaiRequest['verb']);
-            $this->doc = $this->handleIdentify();
+            // $oaiRequest['verb'] = 'Identify';
+            // $this->proc->setParameter('', 'oai_verb', $oaiRequest['verb']);
+            // $this->doc = $this->handleIdentify();
+            throw new OaiModelException('The verb provided in the request is illegal.', OaiModelError::BADVERB);
         }
     }
 
@@ -184,8 +185,17 @@ class RequestController extends Controller
     {
         $repIdentifier = "tethys.at";
         $this->proc->setParameter('', 'repIdentifier', $repIdentifier);
+
+
+
         // Identifier references metadata Urn, not plain Id!
         // Currently implemented as 'oai:foo.bar.de:{docId}' or 'urn:nbn...-123'
+        if (!array_key_exists('identifier', $oaiRequest)) {
+            throw new OaiModelException(
+                'The prefix of the identifier argument is unknown.',
+                OaiModelError::BADARGUMENT
+            );
+        }
         $dataId = $this->getDocumentIdByIdentifier($oaiRequest['identifier']);
 
         $dataset = null;
@@ -203,6 +213,11 @@ class RequestController extends Controller
         $metadataPrefix = null;
         if (true === array_key_exists('metadataPrefix', $oaiRequest)) {
             $metadataPrefix = $oaiRequest['metadataPrefix'];
+        } else {
+            throw new OaiModelException(
+                'The prefix of the metadata argument is unknown.',
+                OaiModelError::BADARGUMENT
+            );
         }
         $this->proc->setParameter('', 'oai_metadataPrefix', $metadataPrefix);
 
diff --git a/app/Http/Middleware/VerifyCsrfToken.php b/app/Http/Middleware/VerifyCsrfToken.php
index 6c8c1c9..f727870 100755
--- a/app/Http/Middleware/VerifyCsrfToken.php
+++ b/app/Http/Middleware/VerifyCsrfToken.php
@@ -11,6 +11,6 @@ class VerifyCsrfToken extends Middleware
      * @var array
      */
     protected $except = [
-        //
+        'oai*',
     ];
 }
diff --git a/app/Models/Oai/OaiModelError.php b/app/Models/Oai/OaiModelError.php
index 5dabd23..16b3f26 100644
--- a/app/Models/Oai/OaiModelError.php
+++ b/app/Models/Oai/OaiModelError.php
@@ -2,6 +2,8 @@
 
 namespace App\Models\Oai;
 
+use App\Exceptions\OaiModelException;
+
 class OaiModelError
 {
 /**
@@ -35,7 +37,7 @@ class OaiModelError
     public static function mapCode($code)
     {
         if (false === array_key_exists($code, self::$oaiErrorCodes)) {
-            throw new Oai_Model_Exception("Unknown oai error code $code");
+            throw new OaiModelException("Unknown oai error code $code");
         }
         return self::$oaiErrorCodes[$code];
     }
diff --git a/routes/web.php b/routes/web.php
index bdf533d..88fbc35 100644
--- a/routes/web.php
+++ b/routes/web.php
@@ -14,7 +14,7 @@ use Illuminate\Support\Facades\Route;
 //Auth::routes();
 //Route::get('/home', 'HomeController@index')->name('home');
 
-Route::get('/oai', ['as' => 'oai', 'uses' => 'Oai\RequestController@index']);
+Route::match(array('GET','POST'), '/oai', ['as' => 'oai', 'uses' => 'Oai\RequestController@index']);
 
 //Route::get('/', 'LocalizationController@index');
 Route::get(