diff --git a/modules/caddyhttp/server.go b/modules/caddyhttp/server.go
index e8bf90058..96bc722c4 100644
--- a/modules/caddyhttp/server.go
+++ b/modules/caddyhttp/server.go
@@ -35,7 +35,9 @@ import (
 type Server struct {
 	// Socket addresses to which to bind listeners. Accepts
 	// [network addresses](/docs/conventions#network-addresses)
-	// that may include port ranges.
+	// that may include port ranges. Listener addresses must
+	// be unique; they cannot be repeated across all defined
+	// servers.
 	Listen []string `json:"listen,omitempty"`
 
 	// A list of listener wrapper modules, which can modify the behavior
diff --git a/modules/filestorage/filestorage.go b/modules/filestorage/filestorage.go
index 355260994..6e688ef0f 100644
--- a/modules/filestorage/filestorage.go
+++ b/modules/filestorage/filestorage.go
@@ -26,6 +26,7 @@ func init() {
 
 // FileStorage is a certmagic.Storage wrapper for certmagic.FileStorage.
 type FileStorage struct {
+	// The base path to the folder used for storage.
 	Root string `json:"root,omitempty"`
 }