diff --git a/composer.json b/composer.json
index 4e69ea5..d3ab012 100644
--- a/composer.json
+++ b/composer.json
@@ -38,7 +38,8 @@
   },
   "require-dev": {
     "php": "^7.4",
-    "friendsofphp/php-cs-fixer": "^3.9"
+    "friendsofphp/php-cs-fixer": "^3.9",
+    "phpstan/phpstan": "^1.8"
   },
   "autoload": {
     "psr-4": {
diff --git a/phpstan.neon b/phpstan.neon
new file mode 100644
index 0000000..e61938c
--- /dev/null
+++ b/phpstan.neon
@@ -0,0 +1,14 @@
+parameters:
+    scanFiles:
+        - src/IntelliSenseHelper.php
+        - ../../oxid-esales/oxideshop-ce/source/oxfunctions.php
+        - ../../oxid-esales/oxideshop-ce/source/overridablefunctions.php
+        - ../../d3/ordermanager/src/IntelliSenseHelper.php
+    paths:
+        - src
+    level: 6
+    phpVersion: 70300
+    checkMissingIterableValueType: false
+    ignoreErrors:
+        - '#d3linkmobility_ordermanager_action::startAction\(\) has no return type specified#'
+        - '#d3linkmobility_ordermanager_action::\$sTplName has no type specified#'
\ No newline at end of file
diff --git a/src/Application/Model/Actions/d3linkmobility_ordermanager_action.php b/src/Application/Model/Actions/d3linkmobility_ordermanager_action.php
index f810dfa..a0a20d5 100644
--- a/src/Application/Model/Actions/d3linkmobility_ordermanager_action.php
+++ b/src/Application/Model/Actions/d3linkmobility_ordermanager_action.php
@@ -39,7 +39,7 @@ class d3linkmobility_ordermanager_action extends d3ordermanager_action_abstract
 {
     public $sTplName = 'd3linkmobility_ordermanager_action.tpl';
     public const ACTIVE_SWITCH = 'blActionLinkmobility_status';
-    public $sTitleIdent = 'D3_LINKMOBILITY_ORDERMANAGER_ACTION';
+    public string $sTitleIdent = 'D3_LINKMOBILITY_ORDERMANAGER_ACTION';
 
     public const SOURCE_TEMPLATE = 'template';
     public const SOURCE_CMS = 'cms';
@@ -98,12 +98,9 @@ class d3linkmobility_ordermanager_action extends d3ordermanager_action_abstract
         /** @var Language $oLang */
         $oLang = oxNew(Language::class);
 
-        $this->getManager()->getRemarkHandler()->addNote(
-            sprintf(
-                $oLang->translateString('D3_ORDERMANAGER_JOBDESC_SENDLMMESSAGE', null, true),
-                $this->getRecipientDescription()
-            )
-        );
+        /** @var string $format */
+        $format = $oLang->translateString('D3_ORDERMANAGER_JOBDESC_SENDLMMESSAGE', null, true);
+        $this->getManager()->getRemarkHandler()->addNote(sprintf($format, $this->getRecipientDescription()));
 
         $this->startExecution();
 
@@ -238,8 +235,9 @@ class d3linkmobility_ordermanager_action extends d3ordermanager_action_abstract
      * @throws StandardException
      * @throws d3ShopCompatibilityAdapterException
      * @throws d3_cfg_mod_exception
+     * @return void
      */
-    public function startExecution()
+    public function startExecution(): void
     {
         try {
             if ($this->canExecuteMethod() && $this->hasRequiredValues()) {
@@ -247,18 +245,18 @@ class d3linkmobility_ordermanager_action extends d3ordermanager_action_abstract
             }
         } catch (emptyMesageException $e) {
             Registry::getLogger()->error($e->getMessage());
-            $this->getManager()->getRemarkHandler()->addNote(
-                Registry::getLang()->translateString('D3_ORDERMANAGER_JOBDESC_SENDLMMESSAGE_EMPTYMESSAGE', null, true)
-            );
+            /** @var string $note */
+            $note = Registry::getLang()->translateString('D3_ORDERMANAGER_JOBDESC_SENDLMMESSAGE_EMPTYMESSAGE', null, true);
+            $this->getManager()->getRemarkHandler()->addNote($note);
         } catch (noRecipientFoundException $e) {
             Registry::getLogger()->info(
                 $this->getManager()->getFieldData('oxtitle')." => ".
                 $this->getItem()->getFieldData('oxordernr').": ".
                 $e->getMessage()
             );
-            $this->getManager()->getRemarkHandler()->addNote(
-                Registry::getLang()->translateString('D3_ORDERMANAGER_JOBDESC_SENDLMMESSAGE_NORECIPIENT', null, true)
-            );
+            /** @var string $note */
+            $note = Registry::getLang()->translateString('D3_ORDERMANAGER_JOBDESC_SENDLMMESSAGE_NORECIPIENT', null, true);
+            $this->getManager()->getRemarkHandler()->addNote($note);
         }
     }
 
diff --git a/src/Application/Model/d3linkmobility_ordermanager_sender.php b/src/Application/Model/d3linkmobility_ordermanager_sender.php
index 6390ff2..c417f68 100644
--- a/src/Application/Model/d3linkmobility_ordermanager_sender.php
+++ b/src/Application/Model/d3linkmobility_ordermanager_sender.php
@@ -93,7 +93,7 @@ class d3linkmobility_ordermanager_sender
              ->getTemplateRenderer();
         $templateEngine = $renderer->getTemplateEngine();
 
-        /** @var $oBasket Basket */
+        /** @var Basket $oBasket */
         $oBasket = $oManager->getCurrentItem()->d3getOrderBasket4OrderManager($oManager);
 
         $oPayment = oxNew(Payment::class);
@@ -146,13 +146,19 @@ class d3linkmobility_ordermanager_sender
     {
         $iOrderLangId = $this->getManager()->getCurrentItem()->getFieldData('oxlang');
         $oLang        = Registry::getLang();
+        /** @var int $iCurrentTplLang */
         $iCurrentTplLang = $oLang->getTplLanguage();
+        /** @var int $iCurrentBaseLang */
         $iCurrentBaseLang = $oLang->getBaseLanguage();
         $oLang->setTplLanguage($iOrderLangId);
         $oLang->setBaseLanguage($iOrderLangId);
+        $content = '';
 
+        /** @var int $iCurrentCurrency */
         $iCurrentCurrency = Registry::getConfig()->getShopCurrency();
-        $iOrderCurr = $this->getManager()->getCurrentItem()->getOrderCurrency()->id;
+        /** @var \stdClass $oOrderCurr */
+        $oOrderCurr = $this->getManager()->getCurrentItem()->getOrderCurrency();
+        $iOrderCurr = $oOrderCurr->id;
         Registry::getConfig()->setActShopCurrency($iOrderCurr);
 
         set_error_handler(
@@ -173,7 +179,7 @@ class d3linkmobility_ordermanager_sender
             $content    = $templateEngine->render($this->getManager()->getValue('sLinkMobilityMessageFromTemplatename'));
         }
 
-        if (false === is_string($content) || false === (bool) strlen($content)) {
+        if (false === (bool) strlen($content)) {
             throw oxNew(emptyMesageException::class, 'message content is empty', $this->getManager()->getFieldData('oxtitle'));
         }
 
@@ -220,9 +226,9 @@ class d3linkmobility_ordermanager_sender
             try {
                 $recipients[] = (oxNew(OrderRecipients::class, $this->getItem()))->getSmsRecipient();
             } catch (noRecipientFoundException $e) {
-                $this->getManager()->getRemarkHandler()->addNote(
-                    Registry::getLang()->translateString('D3_ORDERMANAGER_JOBDESC_SENDLMMESSAGE_NORECIPIENT', null, true)
-                );
+                /** @var string $note */
+                $note = Registry::getLang()->translateString('D3_ORDERMANAGER_JOBDESC_SENDLMMESSAGE_NORECIPIENT', null, true);
+                $this->getManager()->getRemarkHandler()->addNote($note);
             }
         }
         if ((bool) $this->getManager()->getValue('blLinkMobilityMessageToCustom') &&
@@ -233,17 +239,13 @@ class d3linkmobility_ordermanager_sender
                     $recipients[] = oxNew(Recipient::class, $phoneNumber, $countryId);
                 } catch (RecipientException $e) {
                     Registry::getLogger()->info($e->getMessage(), [$phoneNumber, $countryId]);
-                    $this->getManager()->getRemarkHandler()->addNote(
-                        sprintf(
-                            Registry::getLang()->translateString(
-                                'D3_ORDERMANAGER_JOBDESC_SENDLMMESSAGE_RECIPIENTERROR',
-                                null,
-                                true
-                            ),
-                            $phoneNumber,
-                            $countryId
-                        )
+                    /** @var string $format */
+                    $format = Registry::getLang()->translateString(
+                        'D3_ORDERMANAGER_JOBDESC_SENDLMMESSAGE_RECIPIENTERROR',
+                        null,
+                        true
                     );
+                    $this->getManager()->getRemarkHandler()->addNote(sprintf($format, $phoneNumber, $countryId));
                 }
             }
         }