Lex

And Amazon Lex allows to create interactive chatbots.

Amazon Lex is a back-end service it adds capabilities to your application.

So Lex provides text or voice conversational interfaces, allowing you to build voice and text understanding into your application.

Now Lex provides two main functionalities:

  • automatic speech recognition (ASR): speech to text.

  • natural language understanding (NLU) services: Lex discovers your intent and can do intent chaining, which is understanding the context and connecting intents in more sentences.

Amazon Lex is a back-end service, it adds capabilities to your application; it scales well and integrates with other AWS products such as Amazon Connect. It’s quick to deploy and uses a pay as you go pricing model, so it’s perfect for event driven or serverless architectures.

Utterances

Lex also has the concept of utterances.

And when creating an intent you’re able to provide sample utterances, which are ways in which an intent might be said.

For exeample:

  • Can I order a pizza?

  • I want to order a pizza!

  • Give me a pizza!

Fullfillments

In addition to configuring utterances you also have to tell Lex how to fulfill the intent, often this is using lambda integration: if Lex understands that you do want to order a pizza it needs to have some way of initiating that pizza ordering process.

Slots

Slots act like parameters for an intent, and talking to the user will set them to a value.

You might have things like the size of a pizza, small, medium or large. And what type of crust, normal or cheesy.

And you can configure these to be required parameters that go along with an intent.