Join the registry — for listing portals and dealer software

If you run a classifieds portal, a dealer or agency website, or software that publishes listings for many dealers or agencies, you can let AI assistants keep watching your offer for people — in your country, in your language, on your site. Joining is free, needs no account and no approval by us, and usually takes a developer about a day.

What you get#

• People who use AI assistants find your listings. An assistant that reads the registry sees that you serve, say, used cars in Poland, and can leave a person's wish with you ("an estate car under 60 000 zł, petrol, by spring").
• The buyer stays yours. The wish is confirmed on your page, with an e-mail address the person types there. Matches go from you to the person, with links to your listings. Nothing about the buyer passes through the registry or through us.
• No fee, no exclusivity. Listing in the registry is free. You keep your listings, your prices and your contact flow; you can leave at any time.

What you need#

1. A holder descriptor — a small JSON file at https://<your host>/.well-known/isto-intents.json that says who you are and which servers you run (schema, example). To be listed it contains "registry": { "listing": "requested", "terms": "https://istointents.org/registry/terms/" }.
2. One MCP server on the same host, Streamable HTTP, implementing the MCP binding with the consent-link profile: the four tools intent_publish_intent, intent_get_intent, intent_list_matches and intent_withdraw_intent. No sign-in is needed for the assistant: intent_publish_intent returns a link to your page, and only the person can confirm there.
3. Two rules that the check enforces: a tool never asks for or returns contact data (no e-mail, phone, name or address in any tool), and the server is on the host that publishes the descriptor.

How you find matches for a wish — your search, your ranking, your notifications — is up to you. The protocol defines only what an assistant sends and what it gets back.

Steps#

1. Publish the descriptor and the MCP server.
2. Check your host below. The check reads your descriptor and checks your servers exactly as the registry will, but lists nothing — run it as often as you like (once a minute per host).
3. When it says ready, submit your host: POST https://istointents.org/registry/v0/submit with { "host": "<your host>" }. You are listed at once and re-checked automatically; changes to your descriptor appear without a new submission.

A listing is not a certification: the check covers the interface only (how it works). Each operator is responsible for its own service. Registry terms.

Questions#

Write to the editor of the protocol through istointents.com. We do not sell anything here, and you do not need to talk to us to join.