Suppose you are building a booking app on your own. Define the first journey: see available slots, submit a booking, and read a confirmation. Prepare three fixture slots with one already full. Give the agent the inputs, outputs, and files in scope for each slice.
Specify the interface and data together
Use Frontend Design to plan the slot picker, unavailable state, and confirmation view. Give every slot an identifier, time zone, and remaining capacity. Exercise the interface with fixed data before connecting the server so interface and data problems are easier to isolate.
Test a success and a conflict
On success, check the confirmation and saved booking. For a conflict, simulate another user taking the slot and verify that the interface explains what happened and lets the user choose again. Use Webapp Testing to record browser actions and observable results. Verify the saved state in a fresh session.
Leave a handoff for each slice
Record files, fixtures, commands, and open checks. Schedule payment, reminders, and calendar sync as later slices once the booking state is stable.