r/VoiceAIAgent

I own a restaurant, and lately, we have been getting a lot more customer calls. The problem is that I am the only owner, so I can't answer every call while also running the restaurant.

I started looking into AI voice agents and tested VAPI and Omnidimension. Both seem good, but I am still not sure which one is the better choice for my restaurant.

I have also come across Retell AI and a few other platforms.

Has anyone here actually used any of these? Please share your experience so it would be easier for me to make the right decision.

I have tried Vapi, Retell, Pipecat and Bland AI platforms.
So far Vapi is my favorite one of those for more customization options. Also I am using n8n for connecting workflows so they are always accurate.

But since I need very deep customizations even Vapi is sometimes short on that. Because I am not very technical and can’t code I never messed around with LiveKit too much.

So has anyone built a successfully working complex voice agent with LiveKit and can say if it is worth it to learn to at least read code?

Maybe someone has built a successfully working complex voice agent with other platform than LiveKit? If yes, can you share? Thank you:)

Short answer from where I sit: yes, but only to the right client, and figuring out who that is took me a few painful months.

AI voice agents are worth selling to local clients when the client already feels the pain of missed calls. A busy HVAC company in summer, a clinic with a front desk that's drowning, a roofer doing maybe 120 calls a week with one person answering. They get it in thirty seconds because they're already bleeding.

Where it falls apart is the client who answers their own phone, has plenty of time, and just wants something shiny. They churn fast because the agent isn't solving a problem they actually have. I sold two of those early on and both cancelled inside 60 days. My fault, not the product's.

So the real skill isn't building. It's qualifying the buyer hard before you ever pitch. I ask what happens to a call at 7pm now, and how many jobs a missed call is worth to them. If they shrug, I walk.

The money's real when you match it to genuine pain. It's a money pit when you sell it as a gadget.

For folks selling these, what's your filter for a good-fit client versus one who'll cancel in two months?

How long should a Voice AI prompt be?
Tomorrow I'd providing an in-depth teardown of a voice AI provider. They seem to have a suggested prompt limit of 4,000 characters.

My reaction: that feels small.
But the real question is not:
How long should the prompt be?
It is:
What is the prompt responsible for?

If the prompt is only describing the business, the services, the call objective, and the escalation rules, 4,000 characters might be workable.

But *if* the customer also has to teach the AI how to behave as a voice agent, that space disappears fast.
Things like:
Don’t invent details.
Ask one question at a time.
Tool usage.
etc.

That should not all live in the customer prompt.
The business-level prompt should be about the business.
The platform should already provide the voice-agent layer underneath it.
Otherwise, it is like having to teach Excel what the plus sign means before you can use addition.
That would be exhausting.
Voice AI has the same issue.
A good prompt should probably be shorter than people think.
But a good production agent should not depend on one short prompt box.

Ideally there should be layers:
Platform behavior, e.g. The Agent Constitution.
Industry behavior, e.g. How to be a plumber, etc.
Company instructions, e.g. hours of operation and service area.
Knowledge base.
Tool rules.
Escalation rules.
Testing and observability.

So yes, prompt length matters.
But prompt responsibility matters more.
A 4,000-character limit is fine only if the platform is doing a lot of work underneath it.
If it is not, that limit is not simplicity.
It is a ceiling.