diff --git a/gitypeinfo.h b/gitypeinfo.h
index 69d0dad60..a8674fd9b 100644
--- a/gitypeinfo.h
+++ b/gitypeinfo.h
@@ -58,6 +58,18 @@ G_BEGIN_DECLS
  */
 #define GI_TYPE_TAG_IS_NUMERIC(tag) ((tag) >= GI_TYPE_TAG_INT8 && (tag) <= GI_TYPE_TAG_DOUBLE)
 
+/**
+ * GI_TYPE_TAG_IS_CONTAINER:
+ * @tag: a type tag
+ *
+ * Checks if @tag is a container type. That is, a type which may have a nonnull
+ * return from g_type_info_get_param_type().
+ *
+ * Since: 1.72
+ */
+ #define GI_TYPE_TAG_IS_CONTAINER(tag) ((tag) == GI_TYPE_TAG_ARRAY || \
+    ((tag) >= GI_TYPE_TAG_GLIST && (tag) <= GI_TYPE_TAG_GHASH))
+
 GI_AVAILABLE_IN_ALL
 const gchar*           g_type_tag_to_string            (GITypeTag   type);
 
diff --git a/gitypes.h b/gitypes.h
index 47df79039..9c021ff23 100644
--- a/gitypes.h
+++ b/gitypes.h
@@ -425,11 +425,11 @@ typedef enum {
   GI_TYPE_TAG_UTF8      = 13,
   GI_TYPE_TAG_FILENAME  = 14,
   /* Non-basic types; compare with G_TYPE_TAG_IS_BASIC */
-  GI_TYPE_TAG_ARRAY     = 15,
+  GI_TYPE_TAG_ARRAY     = 15,  /* container (see GI_TYPE_TAG_IS_CONTAINER) */
   GI_TYPE_TAG_INTERFACE = 16,
-  GI_TYPE_TAG_GLIST     = 17,
-  GI_TYPE_TAG_GSLIST    = 18,
-  GI_TYPE_TAG_GHASH     = 19,
+  GI_TYPE_TAG_GLIST     = 17,  /* container */
+  GI_TYPE_TAG_GSLIST    = 18,  /* container */
+  GI_TYPE_TAG_GHASH     = 19,  /* container */
   GI_TYPE_TAG_ERROR     = 20,
   /* Another basic type */
   GI_TYPE_TAG_UNICHAR   = 21