When should a voice assistant count a “yes” as yes?
The hardest part of building YzÇağrıMerkezi wasn’t speech recognition. It was consent. Here’s how we decide when an appointment actually gets booked.
YzÇağrıMerkezi is a Turkish-speaking voice assistant for businesses. It answers customer questions and books appointments into free slots. We assumed the hard part would be understanding speech. It wasn’t. The question we spent the most time on was: when exactly should the assistant save a booking?
Not every “yes” is a yes
On the phone, people say “yes” in very different ways. Someone saying “yes, I’m listening” isn’t confirming anything. Someone asking “what happens if I say yes?” hasn’t decided yet. Even “I didn’t say yes” contains the word.
So the assistant looks at the situation, not the word. It first reads back a summary of the booking: day, time, service. Then it waits for a clear confirmation. If it doesn’t get one, it doesn’t save anything and asks again.
A wrong appointment costs more than a missed one.
Saying “I don’t know”
The second rule is simpler: if it couldn’t write to the calendar, it never says “booked”. If the connection dropped or the calendar returned an error, it tells the customer. It doesn’t quietly write somewhere else or carry on guessing.
The same goes for businesses using an external calendar like Cal.com. When we can’t be sure what happened, the slot isn’t released. It stays reserved, and the business checks it from the dashboard.
Things we deliberately don’t do
- Because we can’t verify who’s calling, cancelling or changing an existing appointment just by giving a name is switched off. For now, the business does that from the dashboard.
- We don’t store raw call audio. The dashboard keeps the transcript and the length of each call.
- We don’t “guess” how the customer feels. We only show positive or negative things they explicitly said, along with the exact words.
Why be this careful?
A business tries the assistant in its first week. If it books one appointment at the wrong time that week, the trust is gone and it doesn’t come back. An assistant that asks one more question is better than one that gets it wrong even once.
If you want to try it with your own questions, there’s a 7-day free trial at yzcagrimerkezi.com, no card required.