diff --git a/.github/workflows/pr-reject-png-jpg.yml b/.github/workflows/pr-reject-png-jpg.yml
index b971a839..aa60035d 100644
--- a/.github/workflows/pr-reject-png-jpg.yml
+++ b/.github/workflows/pr-reject-png-jpg.yml
@@ -21,7 +21,8 @@ jobs:
           if [ -n "$IMAGE_FILES" ]; then
             echo "Rejecting merge. PR contains the following JPEG or PNG files:"
             echo "$IMAGE_FILES"
-            echo "Please convert these files to WebP format."
+            echo "Please convert these files to WebP format. For details, see"
+            echo "https://developer.espressif.com/pages/contribution-guide/writing-content/#use-webp-for-raster-images."
             exit 1
 
           else