LinearZeta answers every call.
We replace your outdated phone menu with a conversational AI voice agent that books appointments, gets you the after-hours callback, and recovers the business you're missing — 24/7, on the number you already have.
A missed call is a booked competitor.
For a local service business, the phone is the front door. But most calls arrive while you're with a customer, on a job, or closed for the night — so they hit a menu, a hold, or a voicemail nobody returns.
The caller doesn't wait. They call the next name on the list.
The problem isn't your team. It's that a 1990s phone tree can't hold a conversation, can't book an appointment, and can't work at 9pm on a Sunday. A conversational voice agent can.
One agent that answers like your best front desk.
It picks up on the first ring. It answers the questions you get a hundred times a week, books appointments straight into your calendar, gets you the after-hours callback, and hands real emergencies to a human without missing a beat.
It also does the part most voice bots skip. A caller who wants to move or cancel an appointment doesn't need a confirmation number — the agent finds their booking, reads it back, and changes it. A regular the agent has booked before gets offered their usual service with their usual person when they call to book again. And a restaurant can take a full pickup order by phone, priced off its own menu.
You don't replace your phone number, your team, or your tools. We build the agent, deploy it on your existing line, and run it for you — so you keep the calls you're losing today.
Mapped. Bounded. Measured.
A four-step build that ends in a voice agent you can trust on the phone with your customers.
Map
We map every reason your phone rings — bookings, FAQs, emergencies, after-hours — and decide exactly how each call should end.
Build
We build and voice a conversational agent that knows your business, books into your calendar, and sounds like your front desk — not a robot.
Govern
Clear limits. It never invents prices or makes promises. Real emergencies and edge cases route to a human instantly — anything sensitive always goes to a person.
Measure
You see every call — answered, booked, escalated — in your own dashboard, with a summary of every call, searchable, and what those bookings were worth. A recap lands in your inbox after any month the agent booked something.
Built on infrastructure you can trust.
The same telephony and voice technology that powers companies far larger than yours — assembled, governed, and run for a single line: yours.
Carrier-grade telephony
Your existing number stays put — or start fresh with a dedicated line we provide, your choice. Either way we connect it to the agent through Twilio, the platform behind millions of business phone lines, with no rip-and-replace of your phone system.
Natural, real-time voice
Sub-second, human-sounding speech via ElevenLabs. Callers have a real conversation — not a fight with a menu. It waits for people to finish instead of talking over them, and it filters out the shop noise, the TV, and the other customer at the counter so it hears the person on the phone.
Deployed like software, not edited by hand
Every agent is version-controlled and pushed through a tested pipeline. Changes are reviewed before they ever touch your live line — nothing is fiddled with in a dashboard during business hours.
Disclosure and data care built in
Every call opens by disclosing it's an AI and that the call is recorded. Caller data is minimized. The returning-caller record is keyed on a one-way hash — we never store your callers' numbers in readable form there — and it's scoped to your business alone. Where the business needs to call someone back — a captured lead, a booked appointment — the name and number are kept in readable form for that purpose. They're deleted on request, or within 30 days if the business stops using LinearZeta.
Nothing falls through
If your calendar is unreachable mid-call, the agent doesn't hang up on the caller — it takes their details and the callback request lands with you instead. If a slot gets taken while you're talking, it offers another real opening rather than a promise. And if the line drops mid-booking, it won't book the same person twice.
Monitored daily
We monitor the whole fleet daily and get alerted to trouble on your line before you notice it. If your calendar connection ever expires, it's spotted overnight and you get a one-tap link to reconnect. And a billing hiccup never takes your phone down — that's not a lever we'd pull on a business that runs on its calls.
The agent you launch with is the worst it will ever be.
Most voice bots are configured once and quietly decay from the day they go live. Yours is graded on every single call it answers — and when something falls short, we fix it. You don't have to do anything — it's part of the one plan, along with a monthly tuning and review call where we walk through it with you.
Every call gets graded
The moment a call ends it's scored against explicit written rules for your agent: did it stay inside your information, did it hand off to a human when it should have, did it confirm the appointment properly. Sixteen to twenty-eight separate checks on a typical call, depending on your industry.
Checked against your own information
"Did the agent make something up?" is judged against your real price list, hours, and policies — not against the agent's own confidence. Every call also records any question it couldn't answer, in the caller's own words, so we can tell what it didn't know from what it correctly declined to say.
We fix it — often for everyone at once
What failed gets reviewed and corrected through the same tested pipeline that built your agent. Many corrections land in the shared foundation your industry's agents are built on, so every business on it improves at the same time.
It is not a self-learning bot, deliberately. Your agent never rewrites its own rules — that boundary is exactly why it can be trusted on your line. Every correction is made by a person and reviewed before it reaches your number.
You can see exactly what it did.
The usual answer to "is this thing working?" is a vendor telling you it is. You get a login instead — your own dashboard, showing every call the agent answered and what came of it.
What it was worth
Appointments booked this month, multiplied by what a job is actually worth to you — a number you set, not one we invent. Alongside it: callbacks still owed, calls handled, and how many of those came in after hours or while your line was already busy. The calls you'd have lost. Once you've built up about two months of booking history, two more counts join them: new customers (people booking with you for the first time through the agent) and returning customers (people who booked through it before and booked again).
Every call, searchable
Your whole call history — filter by date, by what happened (booked, transferred, needs follow-up), or search what the call was about. Open any one to read a written summary of what the caller wanted and how it ended. Export the page you're looking at to a spreadsheet.
A callback list you can work
Every caller who needed a callback, with their number, what they asked for, and a summary of the call — and a button to mark them contacted once you've rung back. Nothing to export, nothing to re-key — and the callback alert is emailed to you the moment a call ends, and texted once you opt in. Your line's own number is on there too, so you can call it and hear what your customers hear.
Sign in with your email — no password to lose. Call times show in your business's time zone. A recap lands in your inbox after any month the agent booked something, and you can switch on a weekly one. When callers have recently asked things the agent couldn't answer, the recap email lists the top few, so you can send us the answers and we'll add them. It's included — there's one plan, and the dashboard is in it.
Books straight into the calendar you already run.
The agent writes confirmed appointments directly into your scheduler — no double entry, no separate system to keep in sync. Google Calendar, including several staff members' own calendars; Square Appointments (on Square's Plus plan or higher), per staff member; and Jobber job requests are all included in the one plan. Don't run any of them? It books onto a Cal.com calendar we set up for you — included too.
How the LinearZeta app uses your Google Calendar
LinearZeta is the app your business connects to Google — through a standard Google sign-in you grant during onboarding and can revoke at any time. It asks for calendar access for one purpose: so your voice agent can offer callers times you're actually free and put every confirmed appointment on your Google Calendar, where the rest of your day already lives.
That's the whole job. Calendar access is never used for advertising, never sold, and never read beyond what booking requires. Details are in our Privacy Policy.
On Clio Grow or Mindbody? Available on request — we confirm fit on your call. Ask us.
All product names, logos, and brands are property of their respective owners and are used here only to identify the booking systems we integrate with. Use of a logo does not imply endorsement or partnership.
What good looks like.
These are illustrative targets for a typical appointment-based business, not a guarantee. We set real baselines and targets with you before launch.
Built for businesses that live on the phone.
We work with appointment-driven service businesses across the United States.
Home Services
HVAC, plumbing, electrical, roofing
Learn more →Salons & Spas
Booking, rescheduling, walk-in questions
Learn more →Fitness & Wellness
Class sign-ups, intro offers, membership questions
Learn more →Legal & Professional
Intake, qualification, routing
Learn more →Real Estate
Showing requests, buyer & seller intake, callback requests
Learn more →Nail Salons
Manis, pedis & fills booked 24/7, walk-in & price-list questions
Learn more →We also run agents for restaurants taking pickup orders by phone, auto shops and detailers booking routine service, and independent consultants running intake. Don't see yours? Book a call audit — we'll tell you plainly whether your calls are a fit.
Common questions.
What is an AI voice agent (AI receptionist)?
An AI voice agent is a conversational AI receptionist that answers your business phone, holds a natural conversation, answers common questions, and books appointments straight into your calendar — 24/7. Unlike an old phone tree or IVR menu, callers just talk; unlike a chatbot, it works on the phone. LinearZeta builds and runs it for you.
Do I have to change my phone number?
No. Keep your existing business number — the agent runs on it through Twilio, with no new line, no new hardware, and no rip-and-replace of your phone system. Or have us provide a dedicated number instead if you'd rather keep your personal line private.
How is this different from a call center or answering service?
It is not a room of people. It is a bounded AI voice agent that answers on the first ring, day or night, and books appointments itself. Real emergencies and anything outside its limits are handed to a human. You pay one flat monthly fee with a set number of answered calls included, and any extra is billed per call — not the per-minute rates answering services charge.
How much does it cost?
One plan: $179 a month, everything included. That covers 300 answered calls a month; past that, each extra answered call is a flat $0.50. There is no setup fee, no long-term contract, and nothing held back for a higher tier — every integration and every feature is in. Pay annually and it is $1,790 a year, two months free. See the Pricing page for full details.
More answers — the free trial, per-call billing, calendars — on the pricing page →
One plan. $179 a month. Everything included.
No setup fee, no tiers, and a 14-day free trial — just a simple monthly to run, monitor, and improve your agent. Billed per call, not per minute.
See Pricing →Find out what your phone is costing you.
Book a free call audit. We'll listen to how calls are handled today and show you exactly what a voice agent would catch.
Book a Free Call Audit →