Question

A development team is building a new REST API that returns customer records to internal microservices. By default, the API response includes every field stored on the customer object, including national ID, date of birth, and full address, because the framework auto-serializes the entire entity. Most consuming services only need the customer's name and account status. As the privacy engineer embedded in the team, which approach BEST applies privacy by default to the API design?

Accepted Answer

Configure the API to return only the minimal fields needed for the default use case, requiring consuming services to explicitly request additional fields under a documented, authorized purpose

Answer

Keep the full response payload but encrypt the entire response body in transit using TLS so sensitive fields are protected

Answer

Return all fields by default but add a warning in the API documentation instructing developers not to log or store fields they do not need

Answer

Return all fields but mask national ID and date of birth for every consumer regardless of their authorized purpose