-/** @brief Add a function to the list of "on_exit" functions of the current actor. */
-XBT_PUBLIC void on_exit(std::function<void(int, void*)> fun, void* data);
+/** @brief Add a function to the list of "on_exit" functions of the current actor.
+ *
+ * The on_exit functions are the functions executed when your actor is killed. You should use them to free the data used
+ * by your actor.
+ *
+ * Please note that functions registered in this signal cannot do any simcall themselves. It means that they cannot
+ * send or receive messages, acquire or release mutexes, nor even modify a host property or something. Not only are
+ * blocking functions forbidden in this setting, but also modifications to the global state.
+ *
+ * The parameter of on_exit's callbacks denotes whether or not the actor's execution failed.
+ * It will be set to true if the actor was killed or failed because of an exception,
+ * while it will remain to false if the actor terminated gracefully.
+ */
+
+XBT_PUBLIC void on_exit(std::function<void(bool)> fun);