Who actually carries the messages

When you text an AI agent, your message does not go to the company whose name is on the website. It goes to whoever runs their iMessage infrastructure, and in almost every case that is a third company you have never heard of.

We tried to find out who, for all 33 agents in this directory. Eight say. Twenty five do not.

Every agent that discloses uses the same company

Eight of 33 name the vendor that carries their messages, and all eight name Linq. Three of those eight also name Photon, generally alongside Linq rather than instead of it: Caddy lists both as iMessage delivery, folk uses Linq for iMessage and SMS and Photon for WhatsApp, and Pally uses both plus a Pally-operated Mac in the cloud for the hosted-companion add-on.

Nobody in this set is confirmed on Twilio, Sendblue or LoopMessage for iMessage. Twilio appears three times, but never for blue bubbles: Arlo uses it for phone calls and A2P SMS, Pally for call audio, folk for phone number verification.

That is a concentration worth stating plainly. It is drawn from the eight that disclose, so it describes the disclosing minority and not the market. But no competing vendor appears even once in it.

Why this is hard to find out

The obvious method does not work. We checked the page source of 25 agent sites for the tells that usually give away infrastructure, and found zero. Nothing in the markup of an agent's site names who carries its messages. Unlike analytics or payments, an iMessage provider leaves no script tag, no cookie and no DNS record on the customer's domain.

What works is the disclosure a company is obliged to make. A business that processes personal data has to name its processors, and naming them is the entire purpose of that document. So the answer is published on purpose, on a page almost nobody reads.

The single highest-yield path is /subprocessors. Four of the eight came from a vendor table at exactly that URL. Two more named their provider in the body of the privacy policy instead.

Guessing paths has a ceiling, though. We then read every site's sitemap and footer and fetched everything legal-shaped, 79 pages across 26 agents, and it produced nothing new. At that point the 25 are not hiding it in an unusual place. They are not publishing it.

The other direction: ask the vendor

Three of the eight came from the opposite approach, reading what the providers say about their customers rather than what the agents say about their vendors.

• Tomo appears in a named testimonial on Linq's site calling Linq its closest infrastructure partner and citing hundreds of millions of messages.
• Poke appears in the logo wall under "Trusted by 1,000+ world-class teams", where the image files are served from a folder named Customer logos.
• Ollie appears through its own account, quoted on Linq's site, calling Linq a partner.

Two candidates were rejected, and the reasons matter more than the additions.

Several agents appear in a carousel on Linq's homepage labelled iMessage Agent Store. That is a marketplace, not a customer list. Its own submission form asks you to pick your infrastructure from a dropdown that includes Sendblue, LoopMessage, Photon, BlueBubbles, Blooio, Tuco and self-hosted, so a listing there says nothing at all about who carries the messages. A directory listing is not evidence of infrastructure, and that applies to this directory too.

The second rejection was a testimonial reading "Powered by the best @thelinqapp", signed by a person whose first name matches one of the agents in this directory. He is not connected to it. A name match is not a fact.

What the silence means

Twenty five agents do not say. They split into two groups that are worth keeping apart.

Seventeen publish a privacy policy that names no messaging vendor at all. They name model providers, analytics, hosting and payments, and stop before the company that holds the actual message content.

Eight publish no policy page we could find, which is a different and larger problem for a product that receives personal messages.

None of this is an accusation of wrongdoing. There is no legal requirement to publish a subprocessor table, and plenty of well-run companies do not. But the gap is worth seeing clearly: your messages pass through a company you cannot name, and for 25 of 33 products there is no published way to find out which.

The numbers are not 10DLC

A related finding, from the six agents that publish a contact number.

We looked up the block each number sits in, using public allocation data. All six sit in wireless blocks: five T-Mobile, one Verizon. None sits in the CLEC block a Twilio or Bandwidth number would come from.

Five of those six were recorded in this directory as 10DLC and that was wrong. 10DLC is a long code registered for A2P traffic on the carrier SMS network, and iMessage does not use the carrier SMS network. An agent that reaches you in a blue bubble is not doing 10DLC, whatever else it may also run.

The caveat is on every row: this is the block holder, before number portability, so a number ported away from its original carrier still shows its original assignee. We could not resolve porting, because every free lookup that would settle it requires an account.

Two of the six are among the eight that disclose, both on Linq, and both sit in T-Mobile wireless blocks. Three more unexplained agents sit in T-Mobile wireless blocks too. That is suggestive and nothing more, so their provider stays unrecorded rather than inferred. Two data points do not support publishing a guess about a named company.

If you are choosing an agent

Ask where the messages go. The company you are talking to is rarely the company holding the thread.

The eight that answer in public are giving you something real, and it costs them nothing but candour. That is a reasonable proxy for how a company treats the rest of its disclosure, which is why this directory records it as a field rather than a footnote.

If you are building one

The concentration is the useful signal. If you are choosing infrastructure, the shipped products that disclose have converged on one vendor, and you should understand why before you either follow them or deliberately do not.

It also tells you what your competitors' disclosures will look like. Publishing a subprocessor table is cheap, it is the kind of thing procurement asks for, and right now it puts you in a minority of eight.