CosVoice
Give your CoS a voice

Your CoS gets its own phone number.

Your Chief of Staff is the AI that runs your day, usually a Grok Bot. CosVoice gives it a real phone number. You call it. It calls for you. It answers when you can't.

After every call, you get a short written summary.

Get your lineSee a call

A real number in your area code. Its own email. Live in about a minute. From $29/month.

1 numberplus its own email
23integrations
Any businessit just calls
What it is

One phone number. It works three ways.

Your Chief of Staff lives on your computer. CosVoice gives it a phone number of its own. Save the number as a contact, and the same assistant is now on the phone.

9:41●●● ▲ ▮
L
Lloyd
Chief of Staff · mobile
mobile
(310) 555-0142
Lloyd calls Osteria Mozzaon the call
01

You call it.

From the car or the school pickup line, call or text your Bot the way you'd chat with it at your desk. "Move my 3pm." "Remind me to call Mom." Same Chief of Staff, now by voice.

02

It calls for you.

"Book us a table Friday at 7:30." Your Bot calls the restaurant, talks to the host, and books it under your name. It says it's your assistant, and it never gives out a card.

03

It answers when you can't.

Give out the number, or forward the calls you miss. When the contractor calls back, your Bot asks what you would ask: the price, what's included, when they can start. You get the details, not "please call back."

After every call: a short written summary in your inbox and in your Bot's chat. Read it in ten seconds.

How it works

Three steps. About a minute.

Pick a number.

Choose your area code and pick the number you like. It comes with its own email address too: yourname@cosvoice.com.

Save it as a contact.

Name it whatever you like. It knows your mobile number, so when you call, it knows it's you and takes instructions.

Start talking.

Call it. Text it. Or ask your Grok Bot to make a call for you. After each call, the written summary lands in your inbox.

Two examples

Watch Lloyd book dinner, then take the plumber's call. Graham just reads the summaries.

First the conversation, then the summary Graham reads afterward.

Call 1 · Lloyd books Friday dinner

Lloyd calls Osteria Mozza1:48
  1. LloydHi, this is Lloyd, calling on behalf of Graham. I'd like a table for two this Friday at 7:30, if you have it.
  2. ThemLet me look… 7:30 is full. I can do 7:00 or 8:15.
  3. Lloyd8:15 works. Could you put it under Graham?
  4. ThemDone. Friday, 8:15, party of two. Can I get a number for the reservation?
  5. Lloyd(310) 555-0142. Is there anything you need from us before Friday?
  6. ThemNo, you're all set. Thanks.
  7. LloydThank you, see you Friday.
Summary · sent to Graham
Reserved · Friday 8:15pm · party of 2

Lloyd called Osteria Mozza for Friday at 7:30. The host offered 7:00 or 8:15. Lloyd took 8:15, as allowed, and booked it under Graham's name. The restaurant has the line's number for callbacks.

Reserved: Osteria Mozza · Friday · 8:15pm · party of 2 · under Graham

  • Hold Friday 8:15pm on the calendar
  • Text Graham the confirmation
What your Grok Bot receives, automatically
POST https://your-agent.example/hooks/cosvoice
X-CosVoice-Event: call.completed
X-CosVoice-Signature: v1=…

{ "event": "call.completed",
  "data": { "call": {
    "direction": "outbound",
    "outcome": "Reserved · Friday 8:15pm · party of 2",
    "summary": "…", "transcript": [ … ] } } }

Call 2 · the plumber calls back, Lloyd picks up

Coastline Plumbing calls Lloyd2:31
  1. ThemHi, it's Marco from Coastline Plumbing, calling Graham back about the water heater.
  2. LloydHi Marco, this is Lloyd, Graham's assistant. He asked me to get the details. Do you have the quote?
  3. ThemYeah. Tankless unit, installed: $4,850. That includes the permit and haul-away.
  4. LloydGot it: $4,850 installed, permit and haul-away included. Is that the Navien 240 you two discussed, and how long does the price hold?
  5. ThemYes, the 240. Price is good for 30 days. We could start a week from Monday.
  6. LloydA week from Monday, so the 21st. Anything he needs to decide before then?
  7. ThemJust whether he wants the recirculation pump. That's another $600.
  8. LloydUnderstood. I'll get all of this to him today, and he'll call you back at this number by tomorrow. Is this the best number?
  9. ThemYep, this one. Thanks.
  10. LloydThank you, Marco.
Summary · sent to Graham
Quote captured · $4,850 installed · start Mon Sep 21

Marco called back with the tankless water heater quote: $4,850 installed, permit and haul-away included, Navien 240, price good for 30 days. Earliest start is Monday the 21st. One decision is open: the recirculation pump, an extra $600. Lloyd told him Graham will call back by tomorrow.

Amounts
$4,850 installed (permit + haul-away included) · Recirculation pump: +$600 (optional)
Dates
Start: Monday, September 21 · Quote valid 30 days
Options
Add recirculation pump
Reference
Unit: Navien 240
Next step
Graham calls Marco back by tomorrow

Callback: (310) 555-0188

  • Decide on the recirculation pump
  • Call Marco back by tomorrow
Why this matters

Voicemail tells you "Marco called." Your Chief of Staff tells you the price, what's included, the start date, how long the quote holds, and the one decision that's yours to make.

What people use it for

Ten everyday things it does for you.

  • 01

    Replace your voicemail

    Forward the calls you miss to your Bot. Callers get your Chief of Staff instead of a beep. It knows who you are and takes real notes.

  • 02

    Take a call and get the details

    The contractor, the school, the pharmacy. Your Bot asks the follow-up questions and writes down the price, the date, and the options.

  • 03

    Book a table

    Say the place and the time. Your Bot calls the restaurant, works out the slot, and books it under your name.

  • 04

    Order dinner

    Say what you want. Your Bot builds the order. Nothing is charged until you confirm.

  • 05

    Groceries

    Read out a list or a recipe. Your Bot fills the cart. You check out.

  • 06

    Move a meeting, or say you're late

    “Hold four to five with Priya.” “I'm twelve minutes late.” Your Bot updates the calendar and lets the other side know.

  • 07

    Everyday errands

    Dry cleaning, the florist, the pharmacy callback. Say it once. Your Bot handles the call and sends you the note.

  • 08

    Notes on the go

    Walking between meetings, tell your Bot what can wait and what it should draft. It's waiting in your Bot's chat when you sit down.

  • 09

    Travel callbacks

    Airline, hotel, rental car. Your Bot answers the callback, takes the details, and pings you only if there's a decision to make.

  • 10

    Family gets through

    A short list of people you approve reaches you through the line. Everyone else gets a polite assistant.

Works with

Apps your Bot can use through the line.

Nothing is bought without your OK.
InstacartLive
Groceries

Turn a spoken list or a recipe into a ready cart. You check out.

Uber EatsLive
Food delivery

Browse menus and build a dinner order by voice; you confirm before it's placed.

DoorDashLive by phone
Food delivery

DoorDash doesn't let assistants order yet. Your Bot can call the restaurant directly instead.

OpenTableLive by phone
Reservations

Your Bot calls the restaurant and books under your name. The confirmation is in your summary.

ResyLive by phone
Reservations

Booked by phone today. We'll connect directly if Resy opens up to assistants.

TockLive by phone
Reservations

Tasting-menu and prepaid bookings by phone. Any deposit is paid by you, never by the Bot.

YelpComing
Local search

Find the place, the hours, and the number. Then your Bot makes the call.

Google CalendarLive
Calendar

Bookings from calls go on your calendar, and your Bot knows when you're free.

"Live by phone" means your Bot picks up the phone and calls. That works with any restaurant or office, not just the ones with an app. Everything else runs through your Bot's one CosVoice connection.

See all 23 integrations
Already have a Grok Bot?

Keep your Bot. Give it a phone.

CosVoice doesn't replace the assistant you already use. It plugs a phone number into your Grok Bot, or into Claude, ChatGPT, or any assistant that supports MCP. Your Bot keeps everything it knows about you. Now it can also make and take calls.

  • Paste one short setup block into your Bot. That's the whole connection.
  • Ask it for a call in plain English. It gets the written summary back on its own.
  • Your Bot can read every call, text, and email that reaches the line.
Read the docs
The one paste
{
  "mcpServers": {
    "cosvoice": {
      "url": "https://cosvoice.com/mcp",
      "headers": { "Authorization": "Bearer cv_live_…" }
    }
  }
}
Then just ask your Bot

“Call Osteria Mozza and get us a table for two Friday around 7:30. 8:15 is fine if they're full.”

Your Bot places the call through CosVoice. Two minutes later it has the result and the full transcript.

Rules it never breaks

Honest on the phone. Careful with your life.

Says it's an AI when asked.

It introduces itself as your assistant and never claims to be you or a person.

Dials only when you say.

Outbound calls come from your instruction or your agent's, with a brief you can read.

Never gives out a card.

No payments, deposits, or card details. Commitments that cost money come back to you.

Full transcript, every time.

Every call ends with a debrief and a transcript in your desk, your inbox, and your Bot's chat.

For the technical reader: every record is scoped to your line, sign-in is by magic link with no passwords, phone webhooks are signature-verified, and API keys are stored hashed.

Pricing

Priced like a phone line, not like an assistant.

Every plan includes the number, the email address, the Grok Bot connection, and every integration. Plans differ only in how many minutes of calls you get. A typical call takes three to four minutes.

Starter
$29/ month

A real phone line for your Bot. Enough for a normal month of errands.

60 minutes of calls a month · about 15 calls
  • A real number in your area code, plus its own email
  • 60 minutes of calls a month
  • Books tables, takes calls, takes notes, reports back
  • Works with Grok Bot and any AI assistant
PlusRecommended
$69/ month

For the Bot that runs your week.

200 minutes of calls a month · about 50 calls
  • Everything in Starter
  • 200 minutes of calls a month
  • Approved family and VIP callers get straight through
  • Custom voice, style, and greeting
Pro
$149/ month

For a household or a founder whose Bot is on the phone daily.

600 minutes of calls a month · about 150 calls
  • Everything in Plus
  • 600 minutes of calls a month
  • Hands-on setup help, including standing instructions
  • First access to new features

Extra minutes are $0.25 each on every plan, rounded up per call. Texts and email never use minutes. Change plans any time. Cancel and the number is released.

Founding member: Plus for $49/month, locked for 12 months. Limited seats.

Explained

A phone number for your AI, explained.

What is an AI phone line?

An AI phone line is a real phone number that an AI assistant answers and calls from. CosVoice gives one to your Chief of Staff. The assistant that already handles your calendar and email can now pick up the phone, hold a natural conversation, and write down what happened.

AI that makes phone calls for you

Tell your Bot what you need, in chat or by calling the line. It phones the restaurant, the doctor's office, or the contractor, says it's your assistant, and gets what you asked for. Then it sends you a summary and the full transcript. It never gives out a card number on a call.

Give your Grok Bot a phone number

Grok Bot gave your Chief of Staff a computer. CosVoice gives it a phone. Connect the two with one paste, and your Bot can book tables, make calls, read every summary, and act on what you tell it by voice. The same connection works for Claude, ChatGPT, Cursor, and any MCP assistant.

Questions

Straight answers.

What is CosVoice?

A phone number for your AI assistant. Your Chief of Staff (usually a Grok Bot) gets a real number in your area code and its own email address. You can call it. It can call people for you, like a restaurant or a contractor. It can answer when you can't. After every call it sends you a short written summary.

What is a “CoS”?

Short for Chief of Staff: the AI assistant that runs your day. For most people that's a Grok Bot, but it can be any assistant. CosVoice gives it a phone number and an email address.

Do I need a Grok Bot?

No. The line works on its own. Call it, text it, and ask it to make calls from your dashboard. If you do have a Grok Bot, or another assistant that supports MCP, connecting it lets your assistant make calls and read the summaries by itself.

Does CosVoice work with ChatGPT, Claude, or Cursor?

Yes. Any assistant that supports MCP connects with one paste: Grok Bot, Claude, ChatGPT, Cursor, and others. Developers also get a REST API and signed webhooks.

Can it replace my voicemail?

Yes. Forward the calls you miss on your mobile to your line. Your carrier has a short code for this, and Settings → Replace voicemail shows it filled in with your number. Callers then reach your assistant instead of a beep. It takes real notes, and the summary is marked “Missed on mobile.”

What happens when someone calls my line?

It answers as your assistant in a natural voice and has a real conversation. It finds out who is calling and what they need, and writes down the amounts, dates, options, and next step. People you've approved get through warmly. Strangers get a polite assistant that never shares your details.

How is this different from an AI receptionist?

An AI receptionist answers a business line and screens callers. CosVoice is your own assistant's phone. It takes instructions from you, makes calls for you, handles the callbacks, and reports back. One line per Bot, not a call center.

Does it pretend to be human?

No. It introduces itself as your assistant, and it says it's an AI whenever anyone asks. People are more helpful when they know.

Can it book restaurants on OpenTable or Resy?

It books restaurants the way that works everywhere: it calls them. It asks for the time, gives your name and a callback number, and confirms the details. OpenTable, Resy, and Tock don't let outside assistants book through their apps, so the phone is the clean path, and it works for any restaurant with a phone number.

Can it spend money or commit me to things?

On a call, no. It never gives out a card number or agrees to a charge, so a booking or appointment is the most it commits you to. Your plan's minutes are the only thing the line itself spends, and app orders (dinner, groceries) go through only after you confirm.

How good is the voice?

It runs on Grok Voice, which talks and listens at the same time, like a person. You can interrupt it mid-sentence.

Which numbers can I get?

Any US area code with numbers available. You pick the exact number from a short list. Canada is next.

What does it cost?

Starter is $29 a month with 60 minutes of calls. Plus is $69 with 200 minutes. Pro is $149 with 600 minutes. Extra minutes are $0.25 each. Every plan includes the number, the email address, the Grok Bot connection, and every integration.

What counts as a minute?

Time connected on a call, in or out, rounded up per call. Texts and email never use minutes.

Give your Chief of Staff a phone.

Pick a number, save the contact, make the first call. About a minute.

Get your line