diff --git a/docs/util/cmd_documenter.py b/docs/util/cmd_documenter.py
index 52f3d2cf4..2b93772e8 100644
--- a/docs/util/cmd_documenter.py
+++ b/docs/util/cmd_documenter.py
@@ -82,12 +82,13 @@ class YosysCmdGroupDocumenter(Documenter):
     object: tuple[str, list[str]]
     lib_key = 'groups'
 
-    option_spec = {
+    option_spec = Documenter.option_spec.copy()
+    option_spec.update({
         'caption': autodoc.annotation_option,
         'members': autodoc.members_option,
         'source': autodoc.bool_option,
         'linenos': autodoc.bool_option,
-    }
+    })
 
     __cmd_lib: dict[str, list[str] | dict[str]] | None = None
     @property