An AI voice agent is a telephony system that uses a language model — not a chatbot with a phone number glued on.
Buyers searching AI voice agent development, AI receptionist or Vapi vs custom usually have a working demo and a failing production call. Latency, barge-in, one-way audio and hallucinated transfers do not show up in a marketing video. This service designs the pipeline those demos skip.
UnifiedPBX.in connects STT, an agent runtime and TTS to FreeSWITCH or Asterisk so the switch still owns answer, record, transfer and hangup.
Answer, authenticate, book, take a message, escalate — with keypad fallback when STT is weak.
Campaign pacing, AMD/beep handling, consent language and CRM write-back.
Replace “press 1” trees with intents, then fall back to DTMF when the caller prefers it.
Order status, slot booking, ticket create — via APIs, not prompt fiction.
STT lag, time-to-first-byte TTS, barge-in rate, dead-air and transfer success.
Recording flags, PII in transcripts, retention and “the model must not invent medical advice.”
Answer engines cite pages that define architecture, not slogan lists. This page, the SIP AI voice article, and a public diagram exist so that “how to connect an LLM to a phone call” can resolve to a practitioner who has shipped the media path.
Send the current architecture, call volume, carriers and the workflow you need to automate or productize. Discovery can start from a broken PBX or a blank product brief.
Discuss Your Project hello@unifiedpbx.inA practical technical discussion focused on SIP, media, tenants, AI and the delivery path — not a generic sales deck.