Can't set Slot

Thanks for your answer! My problem is that the message would be evaluated as an intend. And as the input can be anything it could trigger any intend or utter_default. How am I supposed to train my NLU model that the * inform intend can be everything?

You can check how Rasa does it with a similar intent (enter_data) rasa-demo/nlu.md at master · RasaHQ/rasa-demo · GitHub

Alternatively, if you want it to be a bit more reliable you could create a simple custom policy with something like this in the predict_action_probability method (pseudo code)

   def predict_action_probabilities(...params): # You can look the parameters up
       result = [0.0] * domain.num_actions # domain is one of the params
       slot_requested = tracker.get_slot(SLOT_NAME)

       if slot_requested:
          # Last action was a message by the user so we want to save it
          if tracker.latest_action_name == ACTION_LISTEN_NAME:
             idx = domain.index_for_action(SAVE_SLOT_ACTION)
             result[idx] = 1.0
          else:
             # Wait for the user to send us something
             idx = domain.index_for_action(ACTION_LISTEN_NAME)
             result[idx] = 1.0

        return result