Will callers know it isn't a human?

They should, and in many jurisdictions disclosure is required. It also works better in practice: callers who know they are talking to a system are more direct, and the handoff to a person reads as an escalation rather than a bait-and-switch.

Can it transfer to a human mid-call?

Yes, and it should. Warm transfer with a summary passed to whoever picks up is the pattern worth building — the caller should never have to repeat what they just explained.

Voice + SMS · Integration

Alian AI for Twilio

Voice agents, SMS automation, and IVR replacement that doesn't sound like one.

When the conversation needs to happen over phone or SMS, Twilio is the substrate. We build voice agents with low-latency streaming, IVR replacements that feel like a human, and SMS automation for outreach and reminders.

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Things we've built on Twilio

Voice qualification agents (inbound + outbound)
SMS-based appointment reminders + rescheduling
IVR replacement for support routing

How the integration actually works

Call control is TwiML; real-time audio runs over Media Streams, a WebSocket carrying audio in both directions so the model can listen and speak while the call is live. SMS is a much simpler request-and-response surface. For voice we usually put Vapi or Retell on top of Twilio to handle turn-taking and interruption, because that layer is where a call either feels natural or does not.

What to watch for on Twilio

The constraints that decide whether this ships in weeks or drags — worth knowing before you scope, whoever builds it.

Latency is the whole product: People notice conversational delay above roughly half a second, and every hop adds to it — speech recognition, model, synthesis, network. A voice agent that is accurate but slow feels worse than one that is fast and occasionally asks you to repeat. Budget latency before choosing models.
US SMS requires 10DLC registration: Application-to-person messaging to US numbers needs brand and campaign registration, and unregistered traffic gets filtered or blocked by carriers. It takes time and paperwork, and it is the single most common cause of a voice or SMS launch slipping.
Interruption handling separates demos from products: Real callers talk over the agent. Handling barge-in — stopping synthesis mid-sentence and reprocessing what was said — is most of what makes a voice agent feel like a conversation instead of a phone menu.

Questions we get about Twilio

Will callers know it isn't a human?: They should, and in many jurisdictions disclosure is required. It also works better in practice: callers who know they are talking to a system are more direct, and the handoff to a person reads as an escalation rather than a bait-and-switch.
Can it transfer to a human mid-call?: Yes, and it should. Warm transfer with a summary passed to whoever picks up is the pattern worth building — the caller should never have to repeat what they just explained.