BuyerPriya K.+44 •• •••• ••31
Your number+1 555 019 0300agent on the line
SellerHalton Joinery+44 •• •••• ••78
NixflexFor Marketplaces
FOR MARKETPLACESThe moment they swap numbers,
The moment they swap numbers,
you are out of the deal.
Chat filters catch a phone number in a message. They catch nothing once the call happens. Put an agent on your own number so both sides get an instant answer, the booking changes in your systems, and the conversation stays somewhere you can see it.
On your own carrierTwilioTelnyx
Neither side sees the other
The call stays on the platform. So does the record of it.
In short
Voice AI for a marketplace means putting an agent on the numbers you already own, so buyers and providers get an immediate answer without being handed each other contact details. It resolves the call through your own API, and returns the transcript and outcome, which is visibility a platform normally loses the moment a conversation moves to the phone.
● booking changes● no-shows● buyer questions● provider confirmations● disputes● address details● quote follow-ups● off-platform leakage● booking changes● no-shows● buyer questions● provider confirmations● disputes● address details● quote follow-ups● off-platform leakage
SEE IT RUN
A reschedule, start to finish
The call a marketplace gets constantly, and the one most likely to end with two people arranging it privately. Press play and watch it resolve against a live API instead.
Press play to hear how a reschedule runs end to end.
HOW IT WORKS
How does the platform stay in the middle?
1
Both sides call your number
Not each other. The agent answers on a number you own, which is the only version of this where the platform is still in the room when something is agreed.
2
It acts through your API
Checking a provider availability, moving a job, capturing an address, cancelling with a reason. Everything it does is a call into your own systems, so the state of the marketplace stays correct.
3
You keep the record
A transcript, a summary and a structured outcome land on your webhook. That is data you get none of when the two sides swap numbers and sort it out privately.
THE SAME CALL, TWO OUTCOMES
Where the transaction ends up
Without an agent
- Buyer rings the platform, nobody answers
- Provider gives out a mobile number to sort it
- The job is rearranged privately
- The next job is booked directly too
- You see none of it, and take nothing
With an agent
- Buyer rings, answered immediately
- Availability checked through your API
- Job moved and confirmed by text
- Both sides stay on the platform
- Transcript, outcome and take rate intact
WHO IS CALLING
Two sides, two conversations
| Side | The call | What the agent does |
|---|---|---|
Demand | Move or cancel a booking | Checks availability and updates the job |
Demand | Where is my provider | Reads the status and gives a real answer |
Supply | Confirming or declining work | Records it so the job is reassigned early |
Supply | Access details or a delay | Captures it and tells the other side |
Either | A dispute | Transfers to a person with the context |
Separate numbers for each side, one agent template each, all provisioned over the API.
WHY IT MATTERS TO A PLATFORM
What you get back
Visibility into the channel you had none of
Every message on your platform is logged and searchable. Every phone call between the two sides is invisible. Putting the agent on your number turns that black hole into transcripts, outcomes and sentiment, which is worth having even before you count the transactions it keeps.
Convenience is the only real defence
Policies and keyword filters slow leakage down; they do not remove the motive. What removes it is being genuinely easier to use than a private arrangement. An instant answer at nine on a Sunday is a better deterrent than a warning email about terms of service.
A number per side
Demand and supply behave differently, so they get different agents.
Texts the confirmation
Sent during the call, from your number.
Fifteen languages
Marketplaces rarely have one customer base.
Escalates disputes
Straight to a human, with the conversation attached.
WHAT THIS DOES NOT DO
It will not stop two people swapping numbers.
Anybody determined to arrange something privately will manage it, and a vendor telling you otherwise is selling you a fantasy. Leakage is a motivation problem before it is a detection problem. What an agent changes is the balance of convenience: when the platform answers immediately, moves the booking, and confirms it by text, going around it stops being the easier option. That is a smaller claim than eliminating leakage, and it is the one that actually holds.
Related: acting on your API mid-call, a number per side, isolated, and what lands on your server afterwards. Comparing platforms? Nixflex beside Retell, Vapi and Bland.
QUESTIONS
Marketplace questions, answered
Why do marketplaces care about phone calls specifically?+
Because that is where the platform gets cut out. Widely reported industry estimates put off-platform leakage somewhere between a fifth and two fifths of GMV on marketplaces that do not defend against it, and the usual route is a seller suggesting a direct number to skip the fees. Most platforms filter chat for phone numbers, but once a call happens off-platform they see nothing at all.
Does this stop buyers and sellers exchanging numbers?+
Nothing stops two determined people swapping numbers, and we would not claim otherwise. What an agent does is remove the reason to. If a caller can change a booking, get an answer or resolve a problem instantly on your number, the direct swap loses most of its convenience, which is the honest version of how leakage is reduced.
Do we need to build number masking?+
The numbers are already yours, because Nixflex is bring-your-own-carrier. The agent answers on them, so neither side is handed the other personal number by the platform. If you want full proxy pairing between two parties, that is something you build on your carrier with the agent sitting in front of it.
What can it actually resolve?+
The everyday marketplace calls: moving a booking, chasing a provider who has not confirmed, capturing an access detail, answering what is included, and taking a cancellation with a reason attached. Anything it can look up or write through your API, it can do while the caller is on the line.
What happens with a dispute or an angry caller?+
It transfers, with the conversation attached. Disputes are exactly the wrong thing to automate, and the value of the system is partly in recognising that quickly and putting a person on rather than defending the platform position badly.
Can both sides have different agents?+
Yes. Provision separate numbers for the demand and supply sides and attach each to its own agent template, since a buyer asking where the joiner is and a provider confirming a job are completely different conversations.
What data comes back to the platform?+
A transcript, an automatic summary, a sentiment score, the outcome and any fields you asked the agent to extract, delivered on a webhook. For a marketplace this is the interesting part: you gain visibility into a channel that was previously a black hole.
What does it cost at marketplace volume?+
A flat $0.08 per minute of voice with your own carrier underneath. Against a take rate on a job that would otherwise have gone off-platform, the arithmetic is usually straightforward.
Keep the conversation on your platform.
One number, one agent, and the calls stop happening somewhere you cannot see.
Last updated August 2026