What is one purpose of acceptance criteria?

Acceptance criteria serve a critical role in defining the conditions that must be met for a user story to be considered complete and acceptable. These criteria provide clear and specific requirements that outline the expectations for the implementation of the story. By detailing the validation methods—such as functionality, performance, and user experience—acceptance criteria ensure that both the development team and stakeholders have a mutual understanding of what constitutes successful completion. This clarity helps to prevent miscommunication and sets a clear standard against which the completed work can be evaluated, ultimately facilitating a smoother and more efficient validation process.

While summarizing project goals, clarifying team roles, and prioritizing backlog items are important activities within the Agile framework, they do not directly relate to the specific role of acceptance criteria in validating a user story. Therefore, the primary focus of acceptance criteria is their function in quality assurance and validation of user stories, making the identification of how these stories can be validated their main purpose.