Wren — AI Phone Receptionist
An AI phone receptionist for Watson Lake Technology — answers inbound calls, qualifies leads with structured discovery questions, books discovery calls directly into Google Calendar, and emails a structured lead summary after every call.
- Timeline
- 1 week from concept to production
- Role
- Full-stack: Retell AI configuration, system prompt engineering, Cloudflare Worker, Google Calendar integration, Resend integration
- Outcome
- 24/7 inbound call handling
What wasn't working.
Every missed call is a missed lead. Watson Lake needed a way to handle inbound calls professionally around the clock — qualifying prospects, answering service questions, and booking discovery calls — without requiring James to answer every ring.
How we built it.
Built an inbound AI receptionist (Wren) on Retell AI with GPT 4.1 Fast as the LLM. Wren opens every call with a required legal disclosure, runs through a structured 6-question qualification sequence, and books discovery calls directly into Google Calendar during the conversation. A Cloudflare Worker handles all integrations: free/busy checks and event creation via Google Calendar API during the call, and end-of-call fan-out to Resend (structured email summary) after. The system prompt enforces under-20-word responses per turn — voice callers can't re-read, so brevity is everything.
What shipped.
- 24/7 inbound call coverage — no missed leads from after-hours calls
- Calendar bookings happen live during the call — no back-and-forth scheduling emails
- Structured lead summaries arrive in email within 60 seconds of call end
- Hot leads get warm-transferred to James instantly during business hours
- Post-call analysis extracts 12 structured fields from every transcript automatically
Have a system like this to build?
Every project here started as a 30-minute conversation. Tell us what you're trying to ship, and we'll tell you how we'd build it.
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