Entities represents a user interaction, but unlike the Intent, it is usually associated with an adjective, noun, product, services, etc. In most cases, entities complement intentions.
For example, if the the user says: "I want to buy an Apple phone"
The terms "cell phone" and "Apple" will be Entities, because they represent a product and a brand.
Entities can also represent a very specific user interaction, such as an email. In cases where it is impossible to map all possible user interactions, such as an email list, we design a standardized term that will cater for this type of interaction. And for this we use standard type entity.
Often, a response to a user demand will require information that will necessarily be outside the eva, on other servers.
For example, informing a customer's balance, credit card account, closing a purchase on an ecommerce bot...
Here comes the Service cell, which connects the user to eva and the customer.
In it, there is a field to put Webhook. If you have never heard of this expression, it is a protocol used so that an application (APP) on the internet receives real-time information as soon as an event occurs in another web-based application.
The End Cell works like an end point in a flow. By placing this feature, the bot stops communicating at that point. That is, it will only resume the dialog if the user (the bot's interlocutor) interacts again.
The End Cell is always used in a Jump flow, never in the User Journey (the main one).
Imagine two users that have the same intention: checking their bank balance. However, one is already logged into the bank and the other is not. In cases like this, the Rule Cell comes in, to steer each user in the right direction.
This is a feature to make your dialog more assertive and much more precise, especially when Intentions and Entities can bring up multiple scenarios.