How to get user context while creating a custom skill

Summary:

We are creating a custom skill so that employees can apply for absence right from the chatbot. Now, in order to hit the REST APIs to get the desired results we need to put user context (person id/person number in the API). So how do we get that information about the person who is using the chatbot?

Content (required):

We are creating a custom skill so that employees can apply for absence right from the chatbot. Now, in order to hit the REST APIs to get the desired results we need to put user context (person id/person number in the API). So how do we get that information about the person who is using the chatbot?