Configuration api_fields for DataObject on Silverstripe 4 via colymba/silverstripe-restfulapi

I try the colymba/silverstripe-restfulapi for my project i received the Api for my blog but i need more data in Categories & FeaturedImage. my categories & featuredimage:

"FeaturedImage": 13,
"Categories": [
"Tags": [

what i need is the Address link & title of the FeaturedImage & Categories , something like this:

{"ID": 13, 
"Link": "sample/link/address"}
"Categories": [
{"ID": 1,
 "Link": "sample/link/address", 
"Title": "SampleTitle"}

I read these docs and change my configuration for this export but i have some error or nothings to happen What is the correct configuration for this?