diff --git a/run-mypy.sh b/run-mypy.sh
index 43e64854d17710b3e5835c6fe8f2624b9708f162..2d08e14414a52b33baa7c16a4576cd6e68b7e001 100755
--- a/run-mypy.sh
+++ b/run-mypy.sh
@@ -1,3 +1,3 @@
 #! /bin/bash
 
-mypy pytools
+mypy --show-error-codes pytools