Slot filling is the process of gathering required pieces of information to complete a task, where each piece of information fills a “slot” in a structured request. The AI guides conversation to collect all necessary data.
How does slot filling work?
The system defines what information is needed for each task (the slots). As conversation progresses, it extracts values for slots from caller utterances. Missing slots trigger targeted questions. Once all required slots are filled, the task can proceed. Optional slots may be requested or skipped based on context.
Why does slot filling matter?
Most transactions require multiple pieces of information. Appointments need date, time, service type, and contact details. Slot filling provides structure for collecting this information naturally through conversation rather than interrogating callers with a rigid form.
Slot filling in practice
A caller says: “I need to see Dr. Smith next week about my knee.” The AI identifies slots filled (provider: Dr. Smith, timeframe: next week, reason: knee issue) and slots missing (specific date, specific time). It asks: “Dr. Smith has openings Tuesday at 2pm and Thursday at 10am. Which works better for you?” This targets exactly the missing information.