Handling defaulting of values REST

Probably its a question which is already answered by now. But i couldnt find anything which is helping me , hence the ask.

I am developing a REST service which is consumed by multiple teams using javascript/Mobile frameworks.As an example i am the developer of Employees REST service which has exposed GET/POST/PATCH/DELETE. Functionality which the consumers want to achieve is : The employees have address column which gets defaulted when user selects two other values say employee profile ( an attribute in employee) and employee primary contact( an attribute in employee). But they want me to provide it in a way that my WADL/(WADL like open specification) does contain all the information to default a particular value. Ie, which all are dependent values and how to refresh the value of address colum from the other two values.

My question is , How does it handled in outside world. Want to know from experienced devs, on how do you deal with such a usecase today.

Thanks, B1