AnoopKrishna I have come across this type of implementation. but I dont think so we can achieve case opening in harness by Using REST. I consider you need that too! 😃
we can access activity by URL after enabling Allow direct invocation from the client or a service from the security tab.
Example:
http://localhost:8000/prweb?pyActivity=OpenCaseFromLink&Action=openWorkByHandle&InsHandle=ACME-IMPL-WORK%20H-1049
Here OpenCaseFromLink is an activity with Action, InsHandle as params declared in the rule and passed through query string parameters of the URL.
You can create an activity similar to this which opens the work handle and shows in harness. You can have additional param for selection (yes or no) passed in the URL. You can generate and specify inappropriate links in the correspondence.
I hope it helps you ! 😃