In this lesson, you will learn how to use entity resolution in your lambda function.

Use Synonyms in Lambda Functions

Part of good conversational design is responding to users in their own language, i.e. respond with the user's synonym.

Imagine that a user asks for a "scary" movie, but Alexa responds with a "horror" movie. The user's synonym is interpreted correctly by the skill, but the response will not make that clear to the user.

Instead of responding with the resolved value ("horror"), we should respond with the slot value that the user used ("scary"). We can access that with: 

```js
this.event.request.intent.slots.YOUR_SLOT_NAME.value;
```
Repeating back what Alexa heard is a good voice design practice, because it gives the user assurance that they were correctly understood.




Access the synonym (slot value) in Lambda

In the previous exercise you saw that Option 2 (using Entity Resolution) is faster and easier to maintain. Where can you access these synonyms? In the JSON request.

#### About JSON Request
When users interact with your skill, Alexa sends off a JSON request to your AWS Lambda function that looks something like the text file &mdash; **request.js** shown on the right. If your skill uses entity resolution, the JSON request includes some additional important information, including the synonym Alexa heard, the status code of the resolution, and the resolved value. 

In Node, we can access the _synonym_ using:
```js
this.event.request.intent.slots.YOUR_SLOT_NAME.value
```
Where `YOUR_SLOT_NAME` is the desired slot. 

We can access the _status code_ using:
```js
this.event.request.intent.slots.YOUR_SLOT_NAME.resolutions.resolutionsPerAuthority[0].status.code
```

We can access the _resolved value_ using:
```js
this.event.request.intent.slots.YOUR_SLOT_NAME.resolutions.resolutionsPerAuthority[0].values[0].value.name
```






Parse JSON

As you know now, your skill needs to handle synonyms to mimic realistic conversations. To handle synonyms you have two options: with or without Entity Resolution (ER).

**Option 1:** Do it all by yourself. Without Entity Resolution, you would have to catch all of those words as slot values, compare them to a group of values in your AWS Lambda function, and determine which value to return to the user. As you will see in the video, this is the harder and more tedious route. 

**Option 2:** Use Entity Resolution. Alexa's Entity Resolution allows us to create synonyms for our slot values so that we can receive consistent data in our code, but still allows a user to speak in the way that makes sense for them. We are biased towards this, because it’s easy and more efficient. 








Intro


Entity resolution allows us to create synonyms for our slot values, so that we can receive consistent data in our code, but still allow a user to speak in the way that makes sense for them.

Why do we need consistency, you ask? Let’s say we are using the IMDB API to pull a list of movies based on genre. The API only accepts the genre of "action", but your skill must work when the user asks for a synonym, like "battle", "combat", or "war".

Remember that the resolved value is accessed with :
```js
this.event.request.intent.slots.YOUR_SLOT_NAME.resolutions.resolutionsPerAuthority[0].values[0].value.name;
```
In the case of our movie skill, `YOUR_SLOT_NAME` would be `genre`, so you can access the resolved value with:
```js
this.event.request.intent.slots.genre.resolutions.resolutionsPerAuthority[0].values[0].value.name;
```



Access the Resolved Value in Lambda

Now that you can access the status code in the JSON request, what do you do with it?
Using conditional statements, you can tailor your skill's response based on this status code.



Check Resolution Status in AWS Lambda

Nice work, you just learned how you can use synonyms to allow a user to speak in a way that makes sense for them, while providing a means for your skill to still correctly interpret the user's input. 

Let's review what we learned: 

- With Alexa Skills Kit's <a href="https://developer.amazon.com/docs/custom-skills/define-synonyms-and-ids-for-slot-type-values-entity-resolution.html?&sc_category=Earned&sc_channel=RD&sc_campaign=EntityResolution&sc_publisher=Codecademy&sc_content=Content&sc_detail=Design_Course&sc_funnel=Visit&sc_country=WW&sc_medium=Earned_RD_EntityResolution_Codecademy_Content_Design_Course_Visit_WW_AdvancedDevs&sc_segment=AdvancedDevs" target="_blank" rel="noopener noreferrer">Entity Resolution</a>, we can create synonyms for our slot values, so that we can receive consistent data in our code, but still allow a user to speak in the way that makes sense for them.
- Since ER provides you the resolved value, you avoid the need to write complicated code to handle various synonyms, thereby making your code easier to write and maintain.
- The JSON request sent to your Lambda function includes some important information, including the synonym Alexa heard, the status code of the resolution, and the resolved value. 
- We can access the *synonym* using 
```js
this.event.request.intent.slots.yourSlotName.value
```
- We can access the *status code* using
```js
this.event.request.intent.slots.yourSlotName.resolutions.resolutionsPerAuthority[0].status.code
```
- We can access the *resolved value* using
```js
this.event.request.intent.slots.yourSlotName.resolutions.resolutionsPerAuthority[0].values[0].value.name
```
where `yourSlotName` is the desired slot. 


#### More Alexa Resources
- For more Alexa news, <a href="https://build.amazonalexadev.com/alexa-developer-newsletter-subscription-ww.html?&sc_category=Earned&sc_channel=RD&sc_campaign=EntityResolution&sc_publisher=Codecademy&sc_content=Content&sc_detail=Design_Course&sc_funnel=Visit&sc_country=WW&sc_medium=Earned_RD_EntityResolution_Codecademy_Content_Design_Course_Visit_WW_AdvancedDevs&sc_segment=AdvancedDevs" target="_blank" rel="noopener noreferrer">subscribe</a> to the Alexa developer newsletter to stay up-to-date on new features, tutorials, and events.
- <a href="https://forums.developer.amazon.com/spaces/165/index.html?&sc_category=Earned&sc_channel=RD&sc_campaign=EntityResolution&sc_publisher=Codecademy&sc_content=Content&sc_detail=Design_Course&sc_funnel=Visit&sc_country=WW&sc_medium=Earned_RD_EntityResolution_Codecademy_Content_Design_Course_Visit_WW_AdvancedDevs&sc_segment=AdvancedDevs" target="_blank" rel="noopener noreferrer">Alexa Developer Forums</a>
- <a href="https://alexa.design/guide?&sc_category=Earned&sc_channel=RD&sc_campaign=EntityResolution&sc_publisher=Codecademy&sc_content=Content&sc_detail=Design_Course&sc_funnel=Visit&sc_country=WW&sc_medium=Earned_RD_EntityResolution_Codecademy_Content_Design_Course_Visit_WW_AdvancedDevs&sc_segment=AdvancedDevs" target="_blank" rel="noopener noreferrer">Alexa Voice Design Guide</a>
- <a href="https://github.com/alexa?&sc_category=Earned&sc_channel=RD&sc_campaign=EntityResolution&sc_publisher=Codecademy&sc_content=Content&sc_detail=Design_Course&sc_funnel=Visit&sc_country=WW&sc_medium=Earned_RD_EntityResolution_Codecademy_Content_Design_Course_Visit_WW_AdvancedDevs&sc_segment=AdvancedDevs" target="_blank" rel="noopener noreferrer">Alexa code samples and templates</a> on GitHub
- <a href="https://twitter.com/alexadevs" target="_blank" rel="noopener noreferrer">AlexaDevs</a> on Twitter
