Access reference
Domain platform APIs
What each of six platforms will actually let a program do — and what no amount of
asking will get you. Every capability below was confirmed by a live request or read from current
documentation, not assumed.
Still true?
A reference is only worth the date on it. These are the documentation sources we
poll daily; a change to any of them means a claim on this page may have expired.
Atomchecked 2026-08-24
Spaceshipchecked 2026-08-24
Sedochecked 2026-08-24
Dynadotchecked 2026-08-24
Afternicchecked 2026-08-24
Namecheapchecked 2026-08-24
Measured 2026-08-24.
No unreviewed changes.
JSON
What you want, and who gives it
The columns are the jobs; the rows are the platforms. Most gaps are not oversights —
they are deliberate product decisions by the platform.
Platform by platform
Status reflects where things stand today, not what is theoretically possible.
Atom
Connected
MCP · OAuth
The broadest capability of the six, and the only one reached over MCP rather than REST. Already connected — one browser consent produced a refresh token, so it renews itself without anyone signing in again.
Fifteen tools; these matter
get_domain_detailsPrice and listing status for one domainscreen_trademark_conflictsPublic trademark records with filing dates — powers the checkerappraise_domainValuation with reasoning and comparable salessearch_brandable_domainsPriced inventory by concept — needs no login at allgenerate_domain_namesNew candidates, each checked against live availabilityget_checkout_linkPre-filled checkout — where commission is earned
Leave the purchase tools alone. register_domain and the payment-link tools debit a real account. A web page has no business holding that, and the read scope we requested excludes it.
Verified by live tools/list against mcp.atom.com plus a working OAuth refresh token. Source last re-read 2026-08-24, unchanged.
Spaceship
Working
REST · key + secret
Where the portfolio actually lives: 311 domains, 85 of them listed for sale through SellerHub. Keys are already in place and every endpoint below answered on test.
Confirmed working
GET /domainsFull portfolio, paginatedGET /domains/{d}Registration and expiry dates, nameservers, contacts, lock stateGET /domains/{d}/availableAvailability plus premium renewal pricingGET /domains/{d}/transfer/auth-codeTransfer code — in bulk, without the dashboardPUT /domains/{d}/nameserversRepoint DNS across the portfolioGET /sellerhub/domainsWhat you have on sale and at what priceGET /sellerhub/domains/reports/soldCompleted salesGET /dns/records/{d}Read and write zone records
No pricing endpoint exists. Nothing in the API returns what a TLD costs, and the website blocks plain HTTP — which is why those prices are collected through a browser session instead. That is a gap in their API, not a workaround we chose.
Verified by every endpoint below returned 200 against the live account; the published spec holds 38 paths and 50 operations. Source last re-read 2026-08-24, unchanged.
Sedo
One signup away
REST / SOAP · partner id
The single best source of exact listing prices, and the only one that answers for a domain you do not own. Registration is open to any website owner, and it pays rather than costs.
What it returns
DomainStatusTakes a list of domains; returns for-sale flag, price and currency for eachDomainSearchKeyword search across their inventory with prices, up to 1,000 results
To open it: register at
sedo.com/member/partner/register.php. A partner ID arrives immediately and a signing key on approval. Both go into the Worker as secrets and never expire — a genuine machine credential, unlike an OAuth token.
Never scrape Sedo. Their terms forbid “competitor analysis” and “data mining or scraping” by name, and /search is disallowed in robots.txt. The API is free and gives better data, so there is nothing to weigh up.
Verified by current published API documentation; not yet exercised — no partner id issued. Source last re-read 2026-08-24, unchanged.
Dynadot
Open to any account
REST · API key
A hundred and one documented commands, and the most useful ones are not the marketplace ones. Its real value here is bulk operations on domains you own, a public auction feed, and one command nobody expects to find at a registrar.
Public inventory
tld_priceRegistration, renewal and transfer price for every TLD they sell — a machine-readable registrar price feed, free with any accountget_open_auctionsLive auctions with current bidsget_expired_closeout_domainsCloseout inventory and pricesget_auction_bidsBid history on one auction
Your own portfolio
get_transfer_auth_codeTransfer codes in bulkset_ns · set_folder_nsRepoint one domain or a whole folderset_renew_optionAuto-renew across the portfolioget_dns · set_dnssecZone records and DNSSEC
get_listings returns your listings, not anyone's. It reads like a marketplace lookup and is not one — useless for checking a third-party domain, which is the job people assume it does.
Verified by 101 commands enumerated from the published command reference on 2026-08-24. Source last re-read 2026-08-24, unchanged.
Afternic
Closed to buyers
REST · partner only
The largest pool of fixed-price listings, and there is no way to query it. The GoDaddy Aftermarket API is seller-side only: add your listings, remove your listings. No tier lets you ask whether someone else's domain is for sale.
The way around it: Domainr, now part of Fastly, returns a transferable flag meaning the domain sits in Afternic Fast Transfer inventory. That is a licensed signal for the exact fact Afternic withholds — the listing without the price. Ten thousand lookups a month are free.
The price itself needs Referral Partner status, which is a form and a conversation, not a signup. Their own page says the programme is aimed at non-registrar businesses, so it is worth asking — just not worth waiting for.
One caution on the workaround: Domainr’s own API documentation is now headed “deprecated”, because Fastly folded the service into the Fastly API after acquiring it. The transferable flag is still documented and the endpoint still answers, so the capability moved rather than closed — but the entire Afternic route rests on one flag, on a page its owner has marked as legacy. That page is watched daily for exactly this reason.
Verified by GoDaddy Aftermarket API documentation across every published tier. Source last re-read 2026-08-24, unchanged.
Namecheap
Gated, and limited
XML · key + IP allowlist
Full control of domains you hold there, and nothing at all about the marketplace. Namecheap Market resells Afternic and Sedo inventory rather than exposing its own, so there is no listing lookup to reach.
What the namespaces cover
domains.*List, check, register, renew, reactivatedomains.dns.*Hosts, email forwarding, custom DNSdomains.transfer.*Create and track transfersdomains.ns.*Register and update nameserversssl.* · whoisguard.*Certificates and privacy
The threshold is real, and so is the IP allowlist. The account needs 20 domains, or $50 on balance, or $50 spent in two years. Then every calling address must be listed — IPv4 only, ten maximum. That rules out serverless callers unless traffic goes through a fixed egress.
domains.check does return IsPremiumName and a premium price — but that is the registry’s price for a first registration, not an aftermarket listing. The two are easy to confuse and mean different things.
Their documentation cannot be read by a program at all: every page under /support/api/ answers 403 behind a bot challenge, and it does so for a browser User-Agent too, so this is not a robot being turned away politely. What is readable is Namecheap’s own Go SDK, which carries one source file per API method — 83 of them — and that is the surface watched here instead.
Verified by their official Go SDK, method by method; the documentation itself is unreadable to any robot. Source last re-read 2026-08-24, unchanged.
The one thing nobody sells
Worth naming plainly, because it shapes what the product can promise.
There is no aggregator to buy. Dofo, which used to search across marketplaces, now redirects to a security company. NameBio holds historical sale comparables, not live listings. DomainTools and its peers sell registration and hosting history, not asking prices. Resellers of scraped marketplace data exist, and buying from them inherits the source's breach while resting on a supply chain that dies with the next firewall update.
So the aggregation has to be built per source, through the doors each platform actually opens. Which is what the table above is for.