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The Voice Agent gives each business a dedicated phone presence that answers inbound calls, books appointments through your Booking API, updates CRM records, and texts confirmations—all with ElevenLabs Agents Platform for voice, ASR, TTS, and post-call intelligence.

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Product Concept

Always-On Phone Coverage

Incoming calls route from Twilio to an ElevenLabs agent session that greets callers in the business’s voice and handles common intents.

Booking-First

The agent checks live availability via Booking API functions, offers times, and creates/reschedules/cancels bookings with business rules applied.

CRM-Synced

Contacts are upserted in CRM; each call is logged with disposition, summary, transcript link, and booked appointment (if any).

Auto Follow-Ups

After every call, Twilio SMS sends confirmations or recaps. Post-call webhooks from ElevenLabs drive analytics and QA.

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Customer Experience

1

Call Routing

Customer dials a dedicated Twilio number; Twilio bridges the call to the ElevenLabs Agent endpoint (streaming).
2

Branded Greeting & Consent

Agent introduces the business, states hours, and (if configured) asks for recording consent before proceeding.
3

Intent Handling

Agent detects booking vs. info vs. reschedule/cancel vs. escalation. FAQs are answered from knowledge snippets; unclear intents escalate.
4

Booking Flow

Agent calls Booking API functions to fetch availability, proposes options, confirms details, and creates bookings with buffers/blackouts respected.
5

CRM Update

Contact is upserted; call disposition, summary, and transcript URL are written to CRM activity. Booking IDs are linked.
6

Post-Call SMS & Analytics

When the call ends, ElevenLabs Post-Call Webhook triggers a backend handler that sends Twilio SMS (confirmation/recap/follow-up) and records sentiment/summary for QA.

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Functional Scope

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MVP (Phase 1)

  • Inbound calls only; one Twilio number per business routed to an ElevenLabs agent session.
  • Persona configuration (greeting, tone, business info, FAQs) stored in the agent instructions/knowledge.
  • Tooling via ElevenLabs function calling:
    • check_availability(date_range, service_type)
    • create_booking(customer, datetime, service, notes)
    • update_booking(booking_id, changes|cancel)
    • upsert_contact(name, phone, email)
    • log_call(call_id, disposition, summary, transcript_url)
  • Booking API integration with idempotency keys and business rules (buffers, blackout dates).
  • CRM integration for contact upsert + activity logging; store transcript link and booking reference.
  • Post-call webhook ingestion (transcript, summary, sentiment) → CRM update → Twilio SMS send.
  • SMS templates for booking success, info-only recap, follow-up needed.

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Phase 2

  • Outbound/recall flows (return missed calls, reminders).
  • Multi-language/voice variants per business; time-of-day personas.
  • Payments/deposits via payment link in SMS.
  • Human escalation routing (warm transfer) based on low confidence or repeated repair turns.
  • QA dashboard with call scoring, flags for negative sentiment, and manual review queue.

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Phase 3

  • Campaign-style outbound calls (with consent) for reactivation.
  • Adaptive policies by location/service; A/B tested prompts and call flows.
  • Deeper analytics (booking conversion by intent, first-response latency, escalation rates).
  • Advanced PII redaction and retention controls per business.

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Architecture & Dependencies

  • Voice & Intelligence: ElevenLabs Agents Platform (voice model, TTS/ASR, streaming, memory).
  • Function Calling: ElevenLabs tools for Booking API + CRM actions (HTTP adapters in backend).
  • Telephony: Twilio Voice for inbound numbers and PSTN/SIP bridge to the ElevenLabs agent session; Twilio SMS for post-call texts.
  • Webhook Handling: ElevenLabs Post-Call Webhooks for transcript, summary, sentiment, timings; verified via HMAC.
  • Data Storage: Minimal call records (call id, timestamps, disposition, booking id, sentiment flag, transcript URL) with PII minimization and retention controls.
  • Reliability: Retries with idempotency keys on booking/CRM writes; fallback to voicemail/escalation if functions fail.

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Post-Call Workflow

  1. ElevenLabs sends Post-Call Webhook → backend validates signature.
  2. Persist call summary, sentiment, transcript URL, and actionables.
  3. Update CRM activity with disposition and transcript link.
  4. If booking exists, append booking notes; else create follow-up task.
  5. Send Twilio SMS using the appropriate template (confirmation, recap, or follow-up needed).
  6. Emit analytics events (booking conversion, escalation flag, confidence).

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Configuration Surface (Admin)

  • Business profile: name, hours, services/durations, blackout dates, buffers.
  • Persona: greeting script, tone, escalation phrasing, consent message.
  • Knowledge: FAQs/policies ingested into agent knowledge base.
  • Telephony: Twilio number mapping, escalation number, voicemail fallback.
  • SMS: templates and sender ID; enable/disable follow-ups.
  • Compliance: recording consent toggle, redaction settings, retention windows.

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Roadmap & Milestones

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Milestone 1: MVP (2–3 weeks)

  • Provision Twilio number per business; bridge to ElevenLabs agent session.
  • Define persona template + FAQs ingestion into ElevenLabs agent.
  • Implement Booking API + CRM adapters as ElevenLabs functions with idempotency.
  • Build post-call webhook handler (validation, CRM update, Twilio SMS).
  • Basic observability (logs, error alerts, webhook retry queue).

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Milestone 2: Beta Hardening (3–4 weeks)

  • Human escalation path (warm transfer) on low confidence/repair loops.
  • Multi-language/voice variants; holiday/hour-aware prompts.
  • QA flags from sentiment/low confidence; internal review queue.
  • Improved analytics: booking conversion, answer rate, escalation %, SMS delivery.

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Milestone 3: GA (4+ weeks)

  • Outbound callback/reminder flows; campaign-safe outbound with consent.
  • Payment links in SMS and booking notes.
  • Admin console polish; RBAC for multi-location teams.
  • Advanced compliance: PII redaction, per-business retention, audit logging.

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Success Metrics

  • Booking conversion rate from calls.
  • Answer rate / call completion rate.
  • Escalation rate (to human/voicemail) and reasons.
  • SMS delivery success and link click-through.
  • Webhook success rate and average post-call processing time.

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Operational Guardrails

  • Webhook signature verification for ElevenLabs and Twilio.
  • Idempotent writes with retries for booking/CRM actions.
  • Rate limiting and circuit breakers on external dependencies.
  • Clear consent and recording notices; configurable per region.
  • Fallback paths: voicemail or human transfer on repeated errors or low confidence.