diff --git a/tools/load-personoj.lisp b/tools/load-personoj.lisp
index b0e571c5b557da20e34e66816099277f7c6b0d38..4a26756fd2834b8dab4201edf752fc7e1bac4b91 100644
--- a/tools/load-personoj.lisp
+++ b/tools/load-personoj.lisp
@@ -1,9 +1,9 @@
 (defun load-personoj (&optional pth)
   "Load Personoj specification exporter and proof exporter. If given, PTH is the
 path to the root of the repository. Otherwise, the root is taken from the
-environment variable PERSONOJ"
+environment variable PERSONOJPATH."
   (let ((pth (cond
-               (pth (uiop:ensure-pathname pth))
+               (pth (uiop:ensure-pathname pth :ensure-directory t))
                ((uiop:getenvp "PERSONOJPATH")
                 (uiop:getenv-pathname "PERSONOJPATH" :ensure-directory t))
                (t (error "Cannot load personoj: PERSONOJPATH not set.")))))
diff --git a/tools/load-pvs.lisp b/tools/load-pvs.lisp
index 483d9b4f4b732d8711470ef3cfc093804e64ddbf..4365946306823cb5e4f2047be70181b9d5678df7 100644
--- a/tools/load-pvs.lisp
+++ b/tools/load-pvs.lisp
@@ -4,7 +4,7 @@ to the sources of PVS. If not provided, it is fetched from the environment
 variables PVSPATH."
   (let ((pvspath
           (cond
-            (pvspath (uiop:ensure-pathname pvspath))
+            (pvspath (uiop:ensure-pathname pvspath :ensure-directory t))
             ((uiop:getenvp "PVSPATH") (uiop:getenv-pathname "PVSPATH"))
             (t (error "Cannot load PVS: PVSPATH not set.")))))
     (uiop:with-current-directory (pvspath)