diff --git a/src/Jobs/ProcessModelRecordJob.php b/src/Jobs/ProcessModelRecordJob.php
index 0d630f5..84da58e 100644
--- a/src/Jobs/ProcessModelRecordJob.php
+++ b/src/Jobs/ProcessModelRecordJob.php
@@ -41,7 +41,9 @@ public function handle(RecordProcessorManager $manager): void
             $this->modelUploadFile->update([
                 'state' => UploadFileState::error,
                 'error_message' => \sprintf(
-                    'Invalid `null` action for %s type', $this->modelUploadFile->getAttribute('model_type')
+                    'Invalid `null` action for %s type. Valid type is %s',
+                    $this->modelUploadFile->getAttribute('model_type'),
+                    \implode(', ', $manager->getProcessors())
                 ),
             ]);
 
diff --git a/src/Processor/RecordProcessorManager.php b/src/Processor/RecordProcessorManager.php
index fcb0b52..c1f0790 100644
--- a/src/Processor/RecordProcessorManager.php
+++ b/src/Processor/RecordProcessorManager.php
@@ -15,6 +15,11 @@ public function registerRecordProcessors(array $processors): void
         $this->processors = \array_merge($this->processors, $processors);
     }
 
+    public function getProcessors(): array
+    {
+        return $this->processors;
+    }
+
     public function getRecordProcessor(string $modelType): ?ModelUploadRecordProcessor
     {
         $processorClass = $this->processors[$modelType] ?? null;