In our company we use java bean validation for our restful api's. With some constraints it would be helpful to have a bit more context then just a message.
this would allow to have additional data in a constraint violation that can be used together with the message(template) to create a meaningful error response including some structured data, thus making it easy to read and interpret by a machine.
For sure such a feature needs quiet some polishing to make it suitable for all the possible cases. But at least i wanted it to be placed here for further discussion.