Capability caseAI Agents & Voice AI
Voice AI Systems
Voice systems on real telephony: AI receptionists, inbound support, outbound qualification, appointment booking, and CRM-integrated calling, with transcription, call analysis, and escalation to people.
- Enters through
- 03AI Agents & Voice AI
- System type
- Telephony-connected voice agents
- Also demonstrates
- telephony integration · speech · LLM conversation logic · CRM actions · human transfer
- 1Telephony: inbound or outbound callAPIs
- 2Speech recognitionAI
- 3LLM conversation logicAI
- 4Tools and CRM actionsAutomation
- 5Speech synthesisAI
- 6Transcription and call analysisData
- 7Escalation and human transferApplication
01 Context
The class of problem
Phone workloads, from reception and support to outbound qualification and booking, depend on how many people are available to answer. The systems in this capability case handle the routine calls, act in business systems during the call, and hand the rest to a person.
This is a capability case rather than a single client project: it documents the voice systems Qzentra builds and the architecture they share.
What made it non-trivial
- Latency: speech recognition, reasoning, and synthesis have to fit inside a natural conversational pause
- The system has to act in CRMs and calendars during the call, not after it
- Every call needs a safe path to a person
02 The system
Systems we can build
Voice systems are built on a telephony layer, real-time speech recognition, an LLM for conversation logic, tool calls into CRMs and booking systems, and speech synthesis back to the caller. Calls are transcribed and analysed, and anything outside scope is transferred to a person.
System types
- AI receptionist
- Inbound customer support
- Lead qualification
- Outbound calling
- Appointment booking
- CRM-integrated voice workflows
- Transcription and call analysis
- Escalation and human transfer
03 The route
How a voice system works
The loop a single call travels. Recognition, reasoning, and synthesis have to complete inside a conversational pause; the actions run in the business's own systems.
Telephony: inbound or outbound call
APIsA call arrives or is placed through the telephony layer.
Speech recognition
AIThe caller’s speech is transcribed in real time.
LLM conversation logic
AIAn LLM decides what to say and what to do next, inside defined guardrails.
Tools and CRM actions
AutomationDuring the call the system can look up or book, and it logs the call and its outcome to the CRM.
Speech synthesis
AIThe response is spoken back to the caller.
Transcription and call analysis
DataCalls are transcribed and analysed for intents and outcomes, feeding reporting or review.
Escalation and human transfer
ApplicationAnything outside scope, or anything the caller asks for, is transferred to a person.
04 Decisions
Architecture may include
Telephony as the boundary
Twilio, Vapi, or Retell AI carry the call; the rest of the system sits behind that boundary and can change without changing the number the caller dials.
Speech layers tuned for latency
Recognition with Deepgram and synthesis with ElevenLabs are chosen and configured so that the round trip fits a conversational pause.
Actions through webhooks and workflows
CRM lookups, bookings, and logging run through n8n and webhooks, so the voice layer stays thin and the business logic stays in one place.
Escalation designed in
Out-of-scope requests and explicit asks for a person transfer the call with the context so far.
05 Verified outcomes
What these systems are built to do
- Routine inbound and outbound calls handled without a person on the line
- Bookings, lookups, and CRM updates made during the call
- Every call transcribed and analysed
- Calls outside scope transferred to a person
06 Technology and capabilities
Technology, after the architecture
Named last, with the role each played. The capabilities are what the project demonstrates beyond its primary service.
- TwilioTelephony
- VapiVoice agent platform
- Retell AIVoice agent platform
- DeepgramSpeech recognition
- ElevenLabsSpeech synthesis
- LLM APIsConversation logic
- n8n and webhooksWorkflow, CRM, and API integration
Capabilities demonstrated
08 Discuss a project
Have calls that a person is answering when a system could?
Tell us the call types, the systems the voice agent must act in, and when a person should take over. That is the specification to start from.