Assuming you accept things like links and forms, you can get a user-agent to collect input and ad-hoc "job" descriptions from the user and fill in the required structure in your specific application model. It's no more exotic than building up a shopping cart and submitting an order. Once you reify the process, you can add asynchronous monitoring and lifecycle controls as REST operations on these resources.
Don't mistake a custom resource model with server-side processing with a requirement for a custom user-agent. All of the above could be done with pure, form-driven interactions or augmented with client-side processing to provide a slightly nicer UX. Of course, that doesn't mean you will have a generic web service that can perform all different transactions.
Don't mistake a custom resource model with server-side processing with a requirement for a custom user-agent. All of the above could be done with pure, form-driven interactions or augmented with client-side processing to provide a slightly nicer UX. Of course, that doesn't mean you will have a generic web service that can perform all different transactions.