What ydomain offers developers: an HTTP API, webhook callbacks and two embed scripts.

ydomain developer documentation

Three separate things live here. They share one account and one set of listings, and nothing else: you can use any of them without the others.

	What it is	Start at
API	An HTTP API you call. Manage listings, read and answer leads, manage endpoints. Needs an API key.	Authentication
Webhooks	Calls we make to you. A signed `POST` to a URL of yours whenever something changes. Needs no key.	Events and deliveries
Embeds	Two script tags. Put a contact form, or the whole landing page, on a domain you own. Needs nothing at all.	Scripts

Most integrations use two of the three: webhooks to hear that something happened, the API to read the details and act.

The API

Base URL: https://ydomain.com/api/v1
Format: JSON in, JSON out. Send Accept: application/json.
Authentication: a bearer API key on every request.
Version: v1. A breaking change gets a new prefix; fields are only ever added inside v1.

Page	What is in it
Authentication	Keys, abilities, rate limits, pagination, errors
Domains	List, read, create, update and delete listings
Leads	Read enquiries, change status, reply to the buyer
Webhook endpoints	Create and remove endpoints over the API

A first request

curl https://ydomain.com/api/v1/me \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Accept: application/json"

{
  "data": {
    "id": "01920f1a-6c4e-7a51-9d0b-4c8f2b7e1a33",
    "name": "Renee de Vries",
    "email": "[email protected]",
    "locale": "nl",
    "currency": "EUR",
    "abilities": ["domains:read", "leads:read"],
    "counts": {
      "domains": 148,
      "leads": 27
    }
  }
}

GET /me needs no ability beyond a valid key, so it is the quickest way to check that a key works and to see what it is allowed to do.

Conventions

Identifiers are UUIDv7 strings. A listing can also be addressed by its full domain name, so GET /domains/example.com works as well as the id.
Timestamps are ISO 8601 with an offset: 2026-02-14T09:31:07+00:00.
Money is a number plus a separate three-letter currency, never a formatted string. 4950 and "EUR", not "€4.950".
A single record is returned under data. A list is returned under data with links and meta beside it.
Nothing is returned for a delete: the status is 204 with an empty body.
Unknown fields in a request body are ignored, so sending a whole object back after changing one field is safe.

Webhooks

A webhook is the other direction: we POST to a URL of yours, signed, whenever something happens on your account. Endpoints are set up under Settings → Webhooks in the account area, or over the API.

Read Events and deliveries for the list of events, the body we send and how to verify the signature.

Embeds

Two script tags, for a domain you already own: one puts the whole landing page on it, the other puts only a contact form somewhere on your own page. No key, no account setup, nothing to configure — the script works out which listing it belongs to from the page it runs on.

Read Scripts.

Reading these docs as text

Every page is also served as Markdown, which is what you want if you are feeding this to a model or a script:

One page: https://ydomain.com/docs/api/domains.md
Everything at once: https://ydomain.com/docs/llms-full.txt
The index: https://ydomain.com/llms.txt