In an agile-managed project, elaboration is the process of determining the details of a product feature. Whenever the development team tackles a new user story, elaboration ensures that any unanswered questions about it are answered so that development can proceed.
The product owner works with the development team to elaborate user stories, but the development team should have the final say on design decisions. The product owner should be available for consultation if the development team needs further clarification on requirements throughout the day.
Collaborative design is a major part of agile’s success. Watch out for development team members who have a tendency to try to work alone on elaborating user stories. If a member of the development team separates himself or herself from the team, part of the scrum master's job is to coach that person on upholding agile values and practices.