diff --git a/src/kernel_services/cmdline_parameters/parameter_builder.ml b/src/kernel_services/cmdline_parameters/parameter_builder.ml
index 22ea00848f54a287597691ae8362ca1334190d4d..f8e95e6cd38e9c7b1f73905ffb3cd6c440b15470 100644
--- a/src/kernel_services/cmdline_parameters/parameter_builder.ml
+++ b/src/kernel_services/cmdline_parameters/parameter_builder.ml
@@ -577,21 +577,16 @@ struct
   module Make_user_dir_opt
       (Parent: Parameter_sig.User_dir)
       (Info: sig
-         val name: string
+         include Parameter_sig.Input_with_arg
          val env: string option
-         val help: string
+         val dirname: string
        end): Parameter_sig.User_dir_opt
   =
   struct
-    let is_kernel = P.shortname = ""
-    let prefix = "-" ^ (if is_kernel then "" else P.shortname ^ "-")
-
     module Dir_name =
       Filepath
         (struct
-          let option_name = prefix ^ Info.name
-          let arg_name = "dir"
-          let help = Info.help
+          include Info
           let existence = Fc_Filepath.Indifferent
           let file_kind = ""
         end)
@@ -601,7 +596,7 @@ struct
       else
         match Option.bind Info.env Sys.getenv_opt with
         | Some s when s <> "" -> Fc_Filepath.Normalized.of_string s
-        | _ -> Parent.get_dir Info.name
+        | _ -> Parent.get_dir Info.dirname
 
     let set = Dir_name.set
     let is_set = Dir_name.is_set
@@ -611,11 +606,11 @@ struct
       try
         if Extlib.mkdir ~parents:true d' 0o755 then
           P.L.warning "created %s directory `%a'"
-            Info.name Fc_Filepath.Normalized.pretty d';
+            Info.dirname Fc_Filepath.Normalized.pretty d';
         d
       with Unix.Unix_error _ ->
         P.L.abort "cannot create %s directory `%a'"
-          Info.name Fc_Filepath.Normalized.pretty d'
+          Info.dirname Fc_Filepath.Normalized.pretty d'
 
     let get_dir ?(create_path=false) name =
       let dir = Datatype.Filepath.concat (get ()) name in
diff --git a/src/kernel_services/cmdline_parameters/parameter_sig.ml b/src/kernel_services/cmdline_parameters/parameter_sig.ml
index 68162ec68456730d3498e7fb4f80a5f136786bad..6d04fc0d819da735a5d1527572ab7421b3652656 100644
--- a/src/kernel_services/cmdline_parameters/parameter_sig.ml
+++ b/src/kernel_services/cmdline_parameters/parameter_sig.ml
@@ -661,16 +661,14 @@ module type Builder = sig
   module Make_user_dir_opt
       (_: User_dir)
       (_: sig
-         val name: string
-         (** The name of the directory, also used to create an option of the
-             form -<plugin>-<name>. *)
-
+         include Input_with_arg
          val env: string option
          (** Can be used to provide an environment variable that can be used
              instead of the option. The option has higher priority.
          *)
 
-         val help: string
+         val dirname: string
+         (** The name of the directory *)
        end): User_dir_opt
 
   (** Allow using custom types as parameters.
diff --git a/tests/misc/user_directories.unix.t/directories.ml b/tests/misc/user_directories.unix.t/directories.ml
index d4eba52b5e86a45520241924576e01f93fd8a263..e9b949fdf8d073e52ed3f077b47b149cbcf18668 100644
--- a/tests/misc/user_directories.unix.t/directories.ml
+++ b/tests/misc/user_directories.unix.t/directories.ml
@@ -22,18 +22,22 @@ module Sub_cache_opt_no_var =
   Self.Make_user_dir_opt
     (Cache)
     (struct
-      let name = "optnovar"
-      let env = None
+      let option_name = "-dirs-opt-no-var"
+      let arg_name = "dir"
       let help = ""
+      let env = None
+      let dirname = "optnovar"
     end)
 
 module Sub_cache_opt_var =
   Self.Make_user_dir_opt
     (Cache)
     (struct
-      let name = "optvar"
-      let env = Some "FRAMAC_DIRS_VAR"
+      let option_name = "-dirs-optvar"
+      let arg_name = "dir"
       let help = ""
+      let env = Some "FRAMAC_DIRS_VAR"
+      let dirname = "optvar"
     end)
 
 module Config = Self.Config_dir ()