A voice agent that sounds like it is listening,
because it actually is
A voice agent only works if the pauses feel natural and the handoff to a human happens before a caller gets frustrated. We build agents tuned for that, on real phone lines or inside your own app, with a full transcript of every call.
What it is and who needs it
A voice agent handles phone or in-app calls for a scoped purpose, booking an appointment, answering common questions, qualifying a lead, before handing off to a human for anything it should not decide alone. It fits businesses with real call volume where staff spend hours on repetitive calls: clinics, service businesses, anything with a booking flow. It does not replace a receptionist handling nuanced situations; it absorbs the calls that are the same question asked a hundred times a week.
What is inside
The speech pipeline is tuned specifically for natural pacing, pauses in the right places, handling interruptions gracefully, because a voice agent that sounds robotic loses callers before the script even matters. The conversation stays inside a defined scope, booking, qualification, or Q&A, with explicit rules for when to stop and bring in a human rather than guess on a live call. Telephony integration connects to your actual phone line or your app’s calling flow, not a separate number customers have to learn. Every call produces a transcript and a short summary, searchable later, so your team can review what callers actually ask without listening to every recording.
How we build it
We scope the use case tightly first, booking, qualification, or Q&A, resisting the urge to let the agent handle everything on day one, since a narrow scope done well beats a broad scope done poorly on a live call. The speech pipeline gets tuned against real sample calls for pacing and interruption handling before telephony goes live. Escalation rules are tested deliberately: we try to break the script with edge-case questions before a real caller does. Launch starts on one phone line or flow, with transcripts reviewed in the first weeks to catch scope gaps the initial design missed.
What to watch
Voice carries more risk than text because a caller cannot easily re-read a confusing answer, so an escalation rule that is even slightly too narrow leaves real callers stuck on a bad path with no easy recovery. Telephony integration itself is a common source of delay, since provider-specific quirks (call quality, latency, regional number availability) only fully surface once real calls start flowing. Call transcripts need actual human review in the first weeks, not just automated monitoring, because tone and pacing problems are easier for a person to hear than to detect from a transcript alone. Budget time for this review. Budget realistic time for telephony testing across the specific carriers and regions your callers actually use, since call quality and latency behavior differ more between providers than most teams expect going in. A second phone line or market added later often surfaces a new carrier quirk the first one never did, so treat early expansion as a reason to re-test, not just a configuration change.
Timeline and price
| Option | Price | What it covers | Timeline |
|---|---|---|---|
| MVP | from $2,500 | One scripted use case, single phone line, human escalation | 4 to 6 weeks |
| Production | from $6,000 | Qualification plus booking, call transcripts and summaries, volume monitoring | 6 to 8 weeks |
| Full control (handover-ready) | from $10,000 | Everything in Production, plus a full handover package: architecture docs, test suite, admin access audit, and a walkthrough so your own team or another vendor can run it without us | 8 to 10 weeks |
Running cost on top of the build is usually $30 to $100 a month in telephony and model costs, depending on call volume and length.
What you own at the end
You own the call transcripts, the script, the telephony configuration and the full source code. The agent runs on your own infrastructure or a VPS in your name, with a handover document covering the speech pipeline and escalation logic.
Related
Pairs with the AI support agent product for the text-channel equivalent, and speech and transcription product for the underlying audio pipeline. See the AI agents service page for the full range of agent builds we run. Real builds: the visa consulting centre support bots case study and the B2B certification sales agent case study, both built on the same conversation-scoping discipline a voice agent needs. Spending hours a week on calls that ask the same five things? Get in touch.
FAQ
How much does an AI voice agent cost?
From $2,500 for a single scripted use case, booking or basic Q&A, on one phone line. A production build handling qualification, escalation and call analytics runs $6,000 to $10,000.
How long does it take?
Four to six weeks for a single use case once the script and telephony access are ready. Integrating with an existing phone system or PBX can add time depending on the provider.
What is the stack?
Python and FastAPI, a speech-to-text and text-to-speech pipeline, Claude or GPT for the conversation logic, and a telephony provider's API (Twilio or a regional equivalent) or your app's own calling SDK.
Who owns the agent and the call data?
You. Call transcripts, the script, and the code are yours, stored on your own infrastructure with access controls you set. We do not route your call data through a third-party analytics product you have not approved.
What happens when a caller asks something outside the script?
The agent escalates to a human rather than improvising on a live call, where a wrong guess costs more than in text. Every escalation is logged with the transcript so your team can decide whether to extend the script.