diff --git a/src/dune_engine/sub_dirs.ml b/src/dune_engine/sub_dirs.ml
index a921683b0bae..f58051833581 100644
--- a/src/dune_engine/sub_dirs.ml
+++ b/src/dune_engine/sub_dirs.ml
@@ -268,7 +268,7 @@ let decode =
   let data_only_dirs =
     located
       (Dune_lang.Syntax.since Stanza.syntax (1, 6)
-      >>> strict_subdir_glob "data_only")
+      >>> strict_subdir_glob "data_only_dirs")
   in
   let vendored_dirs =
     (* let decode = Predicate_lang.Glob.decode in *)
diff --git a/test/blackbox-tests/test-cases/vendor/main.t/run.t b/test/blackbox-tests/test-cases/vendor/main.t/run.t
index f0b9ac824167..a00062d91dc5 100644
--- a/test/blackbox-tests/test-cases/vendor/main.t/run.t
+++ b/test/blackbox-tests/test-cases/vendor/main.t/run.t
@@ -59,7 +59,7 @@ The current directory cannot be marked as data-only
   1 | (data_only_dirs .)
                       ^
   Error: invalid sub-directory name "."
-  Hint: did you mean (data_only *)?
+  Hint: did you mean (data_only_dirs *)?
   [1]
 
 Only direct subdirectories can be marked as vendored
@@ -81,7 +81,7 @@ Only direct subdirectories can be marked as data-only
   1 | (data_only_dirs a/b/c)
                       ^^^^^
   Error: only immediate sub-directories may be specified.
-  Hint: to ignore a/b/c, write "(data_only c)" in a/b/dune
+  Hint: to ignore a/b/c, write "(data_only_dirs c)" in a/b/dune
   [1]
 
 Multiple direct subdirectories can be marked as data-only or vendored