diff --git a/gobject/gparam.c b/gobject/gparam.c
index ef13f2a51..2c09f5bd6 100644
--- a/gobject/gparam.c
+++ b/gobject/gparam.c
@@ -439,7 +439,8 @@ g_param_spec_is_valid_name (const gchar *name)
  * @blurb, which should be a somewhat longer description, suitable for
  * e.g. a tooltip. The @nick and @blurb should ideally be localized.
  *
- * Returns: (type GObject.ParamSpec): (transfer full): a newly allocated #GParamSpec instance
+ * Returns: (type GObject.ParamSpec): (transfer floating): a newly allocated
+ *     #GParamSpec instance, which is initially floating
  */
 gpointer
 g_param_spec_internal (GType        param_type,
diff --git a/gobject/gsignal.c b/gobject/gsignal.c
index d8a4cd9d9..4e50a2be2 100644
--- a/gobject/gsignal.c
+++ b/gobject/gsignal.c
@@ -1036,8 +1036,8 @@ signal_finalize_hook (GHookList *hook_list,
  * @signal_id: the signal identifier, as returned by g_signal_lookup().
  * @detail: the detail on which to call the hook.
  * @hook_func: (not nullable): a #GSignalEmissionHook function.
- * @hook_data: (nullable): user data for @hook_func.
- * @data_destroy: (nullable): a #GDestroyNotify for @hook_data.
+ * @hook_data: (nullable) (closure hook_func): user data for @hook_func.
+ * @data_destroy: (nullable) (destroy hook_data): a #GDestroyNotify for @hook_data.
  *
  * Adds an emission hook for a signal, which will get called for any emission
  * of that signal, independent of the instance. This is possible only
@@ -1455,7 +1455,7 @@ g_signal_query (guint         signal_id,
  *  for this type. Used to invoke a class method generically. Pass 0 to
  *  not associate a class method slot with this signal.
  * @accumulator: (nullable): the accumulator for this signal; may be %NULL.
- * @accu_data: (nullable): user data for the @accumulator.
+ * @accu_data: (nullable) (closure accumulator): user data for the @accumulator.
  * @c_marshaller: (nullable): the function to translate arrays of parameter
  *  values to signal emissions into C language callback invocations or %NULL.
  * @return_type: the type of return value, or #G_TYPE_NONE for a signal
@@ -1531,7 +1531,7 @@ g_signal_new (const gchar	 *signal_name,
  *  this signal. Used to invoke a class method generically. Pass %NULL to
  *  not associate a class method with this signal.
  * @accumulator: (nullable): the accumulator for this signal; may be %NULL.
- * @accu_data: (nullable): user data for the @accumulator.
+ * @accu_data: (nullable) (closure accumulator): user data for the @accumulator.
  * @c_marshaller: (nullable): the function to translate arrays of parameter
  *  values to signal emissions into C language callback invocations or %NULL.
  * @return_type: the type of return value, or #G_TYPE_NONE for a signal
@@ -1668,7 +1668,7 @@ signal_add_class_closure (SignalNode *node,
  * @class_closure: (nullable): The closure to invoke on signal emission;
  *     may be %NULL
  * @accumulator: (nullable): the accumulator for this signal; may be %NULL
- * @accu_data: (nullable): user data for the @accumulator
+ * @accu_data: (nullable) (closure accumulator): user data for the @accumulator
  * @c_marshaller: (nullable): the function to translate arrays of
  *     parameter values to signal emissions into C language callback
  *     invocations or %NULL
@@ -1929,7 +1929,7 @@ g_signal_set_va_marshaller (guint              signal_id,
  *  %G_SIGNAL_RUN_FIRST or %G_SIGNAL_RUN_LAST.
  * @class_closure: (nullable): The closure to invoke on signal emission; may be %NULL.
  * @accumulator: (nullable): the accumulator for this signal; may be %NULL.
- * @accu_data: (nullable): user data for the @accumulator.
+ * @accu_data: (nullable) (closure accumulator): user data for the @accumulator.
  * @c_marshaller: (nullable): the function to translate arrays of parameter
  *  values to signal emissions into C language callback invocations or %NULL.
  * @return_type: the type of return value, or #G_TYPE_NONE for a signal
@@ -2534,8 +2534,8 @@ node_check_deprecated (const SignalNode *node)
  * @instance: (type GObject.Object): the instance to connect to.
  * @detailed_signal: a string of the form "signal-name::detail".
  * @c_handler: (not nullable): the #GCallback to connect.
- * @data: (nullable): data to pass to @c_handler calls.
- * @destroy_data: (nullable): a #GClosureNotify for @data.
+ * @data: (nullable) (closure c_handler): data to pass to @c_handler calls.
+ * @destroy_data: (nullable) (destroy data): a #GClosureNotify for @data.
  * @connect_flags: a combination of #GConnectFlags.
  *
  * Connects a #GCallback function to a signal for a particular object. Similar
@@ -2812,7 +2812,7 @@ g_signal_handlers_destroy (gpointer instance)
  * @detail: Signal detail the handler has to be connected to.
  * @closure: (nullable): The closure the handler will invoke.
  * @func: The C closure callback of the handler (useless for non-C closures).
- * @data: (nullable): The closure data of the handler's closure.
+ * @data: (nullable) (closure closure): The closure data of the handler's closure.
  *
  * Finds the first signal handler that matches certain selection criteria.
  * The criteria mask is passed as an OR-ed combination of #GSignalMatchType
@@ -2892,7 +2892,7 @@ signal_handlers_foreach_matched_R (gpointer         instance,
  * @detail: Signal detail the handlers have to be connected to.
  * @closure: (nullable): The closure the handlers will invoke.
  * @func: The C closure callback of the handlers (useless for non-C closures).
- * @data: (nullable): The closure data of the handlers' closures.
+ * @data: (nullable) (closure closure): The closure data of the handlers' closures.
  *
  * Blocks all handlers on an instance that match a certain selection criteria.
  * The criteria mask is passed as an OR-ed combination of #GSignalMatchType
@@ -2939,7 +2939,7 @@ g_signal_handlers_block_matched (gpointer         instance,
  * @detail: Signal detail the handlers have to be connected to.
  * @closure: (nullable): The closure the handlers will invoke.
  * @func: The C closure callback of the handlers (useless for non-C closures).
- * @data: (nullable): The closure data of the handlers' closures.
+ * @data: (nullable) (closure closure): The closure data of the handlers' closures.
  *
  * Unblocks all handlers on an instance that match a certain selection
  * criteria. The criteria mask is passed as an OR-ed combination of
@@ -2987,7 +2987,7 @@ g_signal_handlers_unblock_matched (gpointer         instance,
  * @detail: Signal detail the handlers have to be connected to.
  * @closure: (nullable): The closure the handlers will invoke.
  * @func: The C closure callback of the handlers (useless for non-C closures).
- * @data: (nullable): The closure data of the handlers' closures.
+ * @data: (nullable) (closure closure): The closure data of the handlers' closures.
  *
  * Disconnects all handlers on an instance that match a certain
  * selection criteria. The criteria mask is passed as an OR-ed