What are the key components of a well-written user story?

WHAT THIS TESTS:

This question tests whether you can distinguish between a vague feature request and a contract for delivery. Senior engineers are expected to coach product owners and the team to write stories that are independent, negotiable, and testable. The interviewer cares that you understand the narrative format is only the starting point, and that acceptance criteria are the binding definition of done.

A GOOD ANSWER COVERS:

A good answer hits four things in order. First, the narrative structure in the Connextra format: as a persona, I want an action, so that a value is realized. Second, the acceptance criteria, which are specific, binary, testable conditions that answer given-when-then or a simple condition list. Third, the INVEST qualities: stories should be Independent, Negotiable, Valuable, Estimable, Small, and Testable. Fourth, the Three C's: Card, Conversation, and Confirmation, which remind you that a story is a promise for a conversation, not a full specification.

COMMON WRONG ANSWERS:

Common wrong answers include describing acceptance criteria as just another way to phrase the story, writing criteria that are subjective like the page should load fast instead of the page should load in under 200 milliseconds, or forgetting the so that clause and treating the story as a task list for the developer. Another red flag is insisting that only product owners write stories; the reference notes that depending on the product, stories may be written by clients, users, managers, or the development team.

LIKELY FOLLOW-UPS:

Likely follow-ups include how you split an epic into stories, how you handle non-functional requirements in acceptance criteria, what you do when a story fails its criteria during sprint review, and how you prevent scope creep when the conversation phase uncovers new edge cases.

ONE CONCRETE EXAMPLE:

One concrete example is: As a returning customer, I want to save my payment method, so that I can check out faster next time. Acceptance criteria: given I am on the checkout page, when I enter valid card details and check save for later, then the card is tokenized and stored, and given I have a saved card, when I return to checkout, then my saved card is pre-filled and I can complete purchase in one click.