Six checks for a good story.
Bill Wake's INVEST gives a quick quality check for any backlog item. Use it as a lens in refinement, not a gate.
I
Independent
Can be built and released without waiting on another story.
N
Negotiable
The details are open to discussion, not fixed in advance.
V
Valuable
Delivers something a user or customer actually cares about.
E
Estimable
The team understands it well enough to size it.
S
Small
Fits comfortably in a sprint, ideally in a few days.
T
Testable
Clear enough that you can tell when it's done.
Source: XP123: Bill Wake, 'INVEST in Good Stories, and SMART Tasks' ↗
Six checks for a story worth building.