engine.add(ConversationStates.ATTENDING,
behaviour.getProductionActivity(),
new SentenceHasErrorCondition(),
false, ConversationStates.ATTENDING,
null, new ComplainAboutSentenceErrorAction());
/* In the behaviour a production activity is defined, e.g. 'cast' or 'mill'
* and this is used as the trigger to start the production,
* provided that the NPC is not currently producing for player (not started, is rejected, or is complete) */
engine.add(