Last month, a patient called one of our dental clinic clients at 11pm on a Saturday and had a full conversation about rescheduling their root canal — and didn't realize they were talking to an AI until the receptionist mentioned it at their next visit. That wasn't an accident. It was the result of 4 months of prompt iteration, 10,000+ call recordings analyzed, and about 140 prompt versions before we landed on something that actually works. We build Loquent, a production voice AI platform that handles thousands of automated calls per month for healthcare and dental clinics across Canada. The system runs on Anthropic's Claude for conversation logic, Deepgram for speech-to-text, ElevenLabs for text-to-speech, and Twilio for telephony. When we started, our AI sounded like a chatbot reading a script. Now it sounds like a receptionist who's been working at the clinic for three years. The difference was almost entirely in the prompts.…