Introduction:

When a chat user does not provide enough information in the utterance, you can have the chatbot automatically ask for these missing entity values. In this article, we'll explain exactly how this works and what this process is called.

 

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What is slot filling and why is it useful to use?

A specific case where entities come in handy, is when you want to ask the user for missing information. Let's have a look at this example: 

 

U: Hi, I'd like to order a pizza!

B: Great, would you like that small, medium or large?

U: Small

B: Got it! And what topping would you like? I've got mushrooms, pineapple, onion or salami.

U: Mushroom

B: All set! One small pizza with mushrooms on the way!

 

Your chatbot recognises that there is no value for the entity pizza.size or pizza.topping in the user's utterance, so it asks for that information. 

This process of asking for missing entity values is called slot filling. Your chatbot literally asks for entity values to fill empty slots.