diff --git a/build-aux/sync-synopses.scm b/build-aux/sync-synopses.scm
index c1049d3..7d64533 100644
--- a/build-aux/sync-synopses.scm
+++ b/build-aux/sync-synopses.scm
@@ -58,5 +58,15 @@
                 (format (guix-warning-port)
                         "~a: ~a: proposed synopsis: ~s~%"
                         (location->string loc) (package-name package)
-                        upstream)))))
+                        upstream)))
+
+            (let ((upstream   (gnu-package-doc-description descriptor))
+                  (downstream (package-description package))
+                  (loc        (or (package-field-location package 'description)
+                                  (package-location package))))
+              (when (and upstream (not (string=? upstream downstream)))
+                (format (guix-warning-port)
+                        "~a: ~a: proposed description:~%    ~a~%"
+                        (location->string loc) (package-name package)
+                        (fill-paragraph upstream 79 5))))))
           gnus)