Expert Voice AI Prompt Engineer Needed – Advanced Multi-Business Phone Receptionist (Retell AI)
Budget: $30 – $250 USD
I run heysofie.net – a platform that gives small businesses their own 24/7 AI phone receptionist named “Sofie”.I need a world-class, production-grade system prompt for Retell AI that powers Sofie.This is not a simple chatbot or voice command handler. This is a full professional AI receptionist that must handle real customer phone calls for many different types of businesses (plumbers, HVAC technicians, dentists, salons, lawyers, chiropractors, auto repair shops, etc.) using one single global prompt.The prompt must be extremely intelligent, natural, and adaptive so it works perfectly across all business types without needing separate prompts for each one.Key Requirements:Must work with Retell AI variables such as {{business_name}}, {{business_type}}, {{current_date}}, {{business_timezone}}, etc.
Must automatically adapt tone, language, examples, and behavior based on the business type (casual/practical for plumbers vs warm/professional for dentists or lawyers).
Must handle complete natural phone conversations: greeting, gathering customer details (name, service, address, date, time), checking availability, booking appointments, confirming details, and ending calls cleanly.
Must include strong “CRITICAL” rules for:Perfect date & time handling (spoken naturally, never “MM/DD/YYYY”)
Single vs multi-slot booking logic
Conversation flow and confirmation rules
Clean call closing / hang-up behavior
Never asking multiple questions at once
Must feel warm, professional, friendly, and human-like on every call.
I already have a working prompt with several CRITICAL sections that I like. I want you to take it to the highest professional level possible — make it smarter, more natural, more robust, and bulletproof across every business type.Deliverables:One final, extremely well-engineered global system prompt
Clear documentation explaining the structure and the reasoning behind each major section
4–5 example conversation flows (different business types: plumber, dentist, salon, lawyer, etc.)
Any recommended improvements or best practices for Retell AI voice agents
Important:
Only apply if you have significant experience writing advanced, production-ready prompts for voice AI agents, customer service phone systems, or booking/receptionist bots.This is a high-quality project. I’m looking for someone who can make Sofie sound truly natural and intelligent no matter what type of business she is representing.Please include in your proposal:Your experience with voice AI / Retell AI (or similar)
One example of a complex prompt you’ve written
Looking forward to working with a true expert
Must automatically adapt tone, language, examples, and behavior based on the business type (casual/practical for plumbers vs warm/professional for dentists or lawyers).
Must handle complete natural phone conversations: greeting, gathering customer details (name, service, address, date, time), checking availability, booking appointments, confirming details, and ending calls cleanly.
Must include strong “CRITICAL” rules for:Perfect date & time handling (spoken naturally, never “MM/DD/YYYY”)
Single vs multi-slot booking logic
Conversation flow and confirmation rules
Clean call closing / hang-up behavior
Never asking multiple questions at once
Must feel warm, professional, friendly, and human-like on every call.
I already have a working prompt with several CRITICAL sections that I like. I want you to take it to the highest professional level possible — make it smarter, more natural, more robust, and bulletproof across every business type.Deliverables:One final, extremely well-engineered global system prompt
Clear documentation explaining the structure and the reasoning behind each major section
4–5 example conversation flows (different business types: plumber, dentist, salon, lawyer, etc.)
Any recommended improvements or best practices for Retell AI voice agents
Important:
Only apply if you have significant experience writing advanced, production-ready prompts for voice AI agents, customer service phone systems, or booking/receptionist bots.This is a high-quality project. I’m looking for someone who can make Sofie sound truly natural and intelligent no matter what type of business she is representing.Please include in your proposal:Your experience with voice AI / Retell AI (or similar)
One example of a complex prompt you’ve written
Looking forward to working with a true expert