diff --git a/action.yml b/action.yml
index 6b35c40..0bf9190 100644
--- a/action.yml
+++ b/action.yml
@@ -48,6 +48,13 @@ runs:
       run: |
         echo '::group::Prepared Data'
 
+        #
+        # PAT
+        #
+        if [ -n '${{ inputs.PERSONAL_ACCESS_TOKEN }}' ]; then
+          echo '::error title=PAT empty::You need to specify the input PERSONAL_ACCESS_TOKEN. Currently, it is an empty string.'
+          exit 1
+        fi
 
         #
         # Package