Unique Domains MCP server

An MCP server for the Unique Domains API. It lets an AI assistant read domain names, words, TLDs, registrar prices, the domain market, trends and the industry agenda from the Unique Domains catalog.

Every tool reads stored data as of its day. None registers, buys or changes a name.

Hosted, no install and no key: https://mcp.unique.domains/mcp
On your machine: npx -y @uniquedomains/mcp-server

Connect your assistant

Claude

In Claude (web or Desktop), open Customize, then Connectors, click "+ Add", then "Add custom connector", name it Unique Domains and paste https://mcp.unique.domains/mcp. No sign-in is needed. On a Team or Enterprise plan, an Owner adds it in Organization settings, then Connectors, and members connect it from Customize, then Connectors.

To run it on your machine instead, add this to Claude Desktop's claude_desktop_config.json:

{
  "mcpServers": {
    "uniquedomains": { "command": "npx", "args": ["-y", "@uniquedomains/mcp-server"] }
  }
}

Claude Code

claude mcp add --transport http uniquedomains https://mcp.unique.domains/mcp

Or on your machine, with a member key:

claude mcp add uniquedomains -e UD_API_KEY=ud_live_your_key -- npx -y @uniquedomains/mcp-server

Cursor

Add to Cursor (the direct link is cursor://anysphere.cursor-deeplink/mcp/install?name=uniquedomains&config=eyJ1cmwiOiJodHRwczovL21jcC51bmlxdWUuZG9tYWlucy9tY3AifQ==), or put this in .cursor/mcp.json:

{
  "mcpServers": {
    "uniquedomains": { "url": "https://mcp.unique.domains/mcp" }
  }
}

VS Code

code --add-mcp '{"name":"uniquedomains","type":"http","url":"https://mcp.unique.domains/mcp"}'

Or in .vscode/mcp.json:

{
  "servers": {
    "uniquedomains": { "type": "http", "url": "https://mcp.unique.domains/mcp" }
  }
}

ChatGPT

Go to chatgpt.com/plugins, select the plus button, then "Add custom MCP server". Name it Unique Domains, enter https://mcp.unique.domains/mcp as the server URL with no authentication, then "Create as a plugin". Install the plugin, then in a new conversation type @ and pick it. Your account's or workspace's policies decide whether custom servers can be added.

Any other client

Streamable HTTP at https://mcp.unique.domains/mcp, or stdio with npx -y @uniquedomains/mcp-server.

Plugins

The plugin/ folder is a plugin for the AI assistants that take one. It holds the hosted connector and one skill, which tells the assistant which tool answers which question. It runs nothing on your machine and uses no key.

In Claude Code, run this line:

/plugin install unique-domains --marketplace UniqueDomains/mcp-server

Claude Code asks you to confirm this repository as a marketplace, then opens the plugin's page, where you install it. The line needs Claude Code 2.1.275 or later. On an earlier version, do the same in two steps:

/plugin marketplace add UniqueDomains/mcp-server
/plugin install unique-domains@uniquedomains

Three other tools read files of this repository. Grok Build reads plugin/.grok-plugin/plugin.json, in the same folder. Gemini CLI reads gemini-extension.json at the root, which adds the hosted connector without the skill. For Devin, npm run plugin:devin builds the folder its marketplace takes.

Free tools and a member key

Without a key, the server answers what the Unique Domains website shows anyone: a name's status and registry record, an ending's facts, registrar prices, market aggregates, trends and the agenda.

A member key adds the keyed tools of its plan, the Founder or the Investor plan. Create the key in Unique Domains under Settings, Account, API, then pass it to the server on your machine:

UD_API_KEY=ud_live_your_key npx -y @uniquedomains/mcp-server

The server reads the key's plan once at start and lists the tools that plan opens. The plans are described at unique.domains/api.

The hosted connector serves the free tools only and takes no key. Five free tools are on the npm server only. Three answer one word or one ending a caller a day, and the hosted connector is one caller for all its users: ud_get_market_sales_word, ud_get_word_market, ud_list_tld_prices. ud_get_domain answers what ud_get_name answers, and ud_get_meta_freshness reports how current each part of the data is, which every answer's meta already dates.

What an answer holds

structuredContent: the API's data, meta and links, as the tool's output schema describes them.
content: one line for a reader (the name and its headline fact, or the row count and the first names), then the same JSON as text.
links.details: the public Unique Domains page about the subject, when there is one (hosted connector).
On the hosted connector, internal ids (catalog ids, row ids, UUIDs) are left out, times become their UTC day (an auction's deadline keeps its hour), and the stamps of when a figure was computed are dropped. The npm server and the API keep them.
A list answers 20 rows by default. When meta.cursor is set, pass it as cursor to read the next page.
A refusal is a sentence the assistant can act on: what was wrong, what is accepted, or when a limit resets.

Privacy and security

What the connector logs. Nothing of its own. It stores no question, no answer and no caller. It passes each tool's input to the Unique Domains API, and the API's request log keeps one line per call for 12 months: the path, which holds the name or word asked about, with its time, its status and how long it took. A monthly job deletes older lines. The connector calls the API under its own name, so the API never sees your address or an account of yours. When your assistant runs on your own machine, it connects to the connector from your IP address. The connector's hosting providers see it, as they see the address behind any web request, and the connector does not store it. Section 8 of the privacy policy says what the API keeps and why.
Registry records. A name's registry answer repeats the registry's public record, which can include the holder's name or organization when the registry publishes it.
Every origin is accepted. /mcp answers any Origin with Access-Control-Allow-Origin: *. The server is public, needs no sign-in, holds no session and never serves a member key over HTTP, so checking the origin would protect nothing, and strict origin checks break some assistants' own clients.
HTTPS only. The hosted connector answers over HTTPS and sends Strict-Transport-Security: max-age=31536000.
Reporting a vulnerability. Write to contact@unique.domains; please do not open a public issue for it.

The same data elsewhere

The API reference: unique.domains/api
The SDK and the command line: UniqueDomains/nodejs (@uniquedomains/sdk, @uniquedomains/cli)
The open datasets on GitHub: one-word domains, expiring one-word domains, the daily editions, the 2026 new gTLD applications and the rest of the organization

Tools

56 tools answer without a key (51 on the hosted connector); a member key adds 25 more, the Investor ones for an Investor key only.

Tool	What it reads	Needs
`ud_get_name`	Stored answer for one domain name	free
`ud_batch_names`	Stored answers for up to 100 domain names in one call	Investor key
`ud_check_name`	Reads one name live from its registry and a registrar	member key
`ud_get_name_prices`	Every stored registrar quote for one name	member key
`ud_get_name_registry`	Latest stored registry record of one name	free
`ud_get_name_registry_history`	Stored registry record versions of one name and what moved between them	Investor key
`ud_get_name_dns`	Latest stored DNS reading of one name	free
`ud_list_name_changes`	Change events of one name, newest first	Investor key
`ud_get_name_history`	Web history of one name in bands	Investor key
`ud_get_name_value`	Stored value estimate of one name and its last 20 estimates	member key
`ud_appraise_name`	Runs the appraisal of one stored name when its estimate is missing	Investor key
`ud_get_name_comps`	Similar-sales aggregate of one name and how many endings its word sold on	free
`ud_get_name_auction`	Open auction of one name, if any	free
`ud_resolve_word`	Turns what a caller typed into the catalog word it names	free
`ud_list_word_categories`	Catalog's word categories, by name	free
`ud_batch_words`	Up to 100 word profiles in one call	Investor key
`ud_list_words`	Searches the catalog's words by text and facets	member key
`ud_get_word`	A word's profile	member key
`ud_get_word_endings`	A word's endings as stored on the latest day	free
`ud_list_word_names`	A word's catalog names on the endings that sell, by name	member key
`ud_get_word_trademarks`	A word's trademark counts and its exact-match marks	Investor key
`ud_get_word_notability`	A word's Wikipedia and Wikidata facts	free
`ud_get_word_market`	A word's stored sales and auction aggregates	free, npm only
`ud_list_related_words`	A word's synonyms then related words	Investor key
`ud_list_word_fits`	How well the word fits each ending whose keywords list it	Investor key
`ud_request_word`	Brings a word into the catalog	Investor key
`ud_get_word_request`	State of a word request	Investor key
`ud_list_domains`	One-word catalog names under filters	free
`ud_get_domain`	One catalog name, by name or catalog id	free, npm only
`ud_list_expiring_domains`	Catalog names expiring or expired, by expiry day	Investor key
`ud_get_domain_drops`	Names dropping on one day, counted by ending	free
`ud_list_domain_hacks`	Domain hacks	free
`ud_list_domain_changes`	Changes across the catalog's names, newest first	Investor key
`ud_get_catalog_stats`	Catalog headline totals for the latest day	free
`ud_list_tlds`	Every root TLD with its registry facts and launch phases	free
`ud_get_tld`	One TLD in full	free
`ud_get_tld_stats`	Ending's latest market figures	free
`ud_list_tld_phases`	Every dated launch phase of the ending, chronological	free
`ud_list_tld_changes`	Ending's public registry changes, newest first	free
`ud_list_tld_keywords`	Keywords the catalog attaches to the ending, by type	free
`ud_list_tld_applications`	2026 new gTLD round as ICANN publishes it	free
`ud_list_tld_application_changes`	Every recorded status or contention change of the round	free
`ud_get_tld_application_string`	One applied-for string	free
`ud_list_registrars`	Nine registrars whose daily price lists are compared	free
`ud_list_registrar_prices`	A registrar's list prices, alphabetical by ending	free
`ud_list_registrar_changes`	A registrar's confirmed list-price changes, newest first	free
`ud_get_registrar_footprint`	Names tracked under the registrar on the latest footprint day	member key
`ud_list_tld_prices`	Every registrar's list price for one ending	free, npm only
`ud_list_tld_price_history`	Change-only price rows of one ending, newest first	Investor key
`ud_list_price_changes`	Confirmed registrar price changes across the nine	free
`ud_list_price_traps`	Endings whose cheapest first year renews at a trap price	free
`ud_list_cheapest_prices`	Cheapest registrar per ending for up to 100 endings	member key
`ud_list_venues`	Parking and marketplace venues with a profile and their rounded footprint	free
`ud_get_venue`	One venue's profile with its verified listing terms	free
`ud_list_iana_registrars`	IANA registrar list as stored, by IANA id	free
`ud_get_iana_registrar`	One IANA registrar by id	free
`ud_get_market_sales`	Domain sales pulse as headline aggregates	free
`ud_list_market_sales_series`	One sales series by day, week or month, oldest first	free
`ud_list_market_sales_endings`	Each ending's 12-month and 30-day sales figures	free
`ud_get_market_sales_lengths`	Sales by label length for .com, .ai, .io and .co	free
`ud_list_market_sales_movers`	Up to ten words whose sales moved over the last 30 days	free
`ud_get_market_sales_word`	One word's sales market over 12 months	free, npm only
`ud_get_market_auctions`	Today's domain auctions by venue	free
`ud_list_market_auctions_sample`	Day's fixed sample of up to 20 single-word names at auction	free
`ud_list_market_auction_venues`	Seven auction venues with their verified rules and today's counts	free
`ud_list_market_auction_outcomes`	Confirmed auction outcomes by venue	Investor key
`ud_list_trends`	Every published trend with its latest edition figures and its first and last edition day	free
`ud_get_trend`	One trend	free
`ud_list_trend_categories`	Trend categories, to narrow the trends by	free
`ud_list_trend_pool`	Trend candidates the daily editions draw from	member key
`ud_list_events`	Industry events of one month	free
`ud_get_event`	One industry event with its organizer	free
`ud_get_agenda`	Whole public agenda of one month	free
`ud_get_latest_edition`	Latest daily edition of Business Ideas or Trending Domains	free
`ud_get_edition`	One dated daily edition of Business Ideas or Trending Domains	free
`ud_get_meta_enums`	Every list of values the answers use	free
`ud_get_meta_freshness`	How current each part of the stored data is	free, npm only
`ud_list_meta_datasets`	Free GitHub datasets that hold the same rows as these answers	free
`ud_list_meta_trademark_classes`	45 Nice classes a trademark is filed under	free
`ud_get_meta_providers`	Registrar identities and the auction venue and parking service catalogs	free
`ud_get_key`	What the calling member key opens	member key

Settings

Variable	Profile	What it does
`UD_API_KEY`	local	A member key: adds the keyed tools of its plan.
`UD_MCP_PROFILE`	both	`local` (the default) or `hosted`.
`UD_API_BASE`	both	Another API base, for a local run of the API.
`UD_CONNECTOR_SECRET`	hosted	The connector's shared secret, sent as `X-UD-Connector-Secret`.
`UD_WELLKNOWN_FILES`	hosted	Files served under `/.well-known/`, as a JSON object (see below).
`PORT`	hosted	The HTTP port, 8080 by default.

The hosted profile registers the free tools only, sends no Authorization header whatever UD_API_KEY holds, removes the register and product links from answers and adds links.details. Without a key (the hosted profile, or the npm server with no UD_API_KEY), the inputs only a key may send, such as sort or prefix, are not listed.

UD_WELLKNOWN_FILES maps a file name to its body (served as plain text) or to { "body": "...", "contentType": "..." }, so a directory's proof takes a variable change and no deploy:

{
  "openai-apps-challenge": "<the token from OpenAI's portal>",
  "mcp-registry-auth": "v=MCPv1; k=ed25519; p=<public key>",
  "glama.json": { "body": "{\"$schema\":\"https://glama.ai/mcp/schemas/connector.json\",\"claim\":\"<token>\"}", "contentType": "application/json" }
}

Run the hosted connector yourself

docker build -t uniquedomains-mcp-server .
docker run -p 8080:8080 uniquedomains-mcp-server

The image runs node dist/http.js with UD_MCP_PROFILE=hosted: POST /mcp (stateless Streamable HTTP, plain JSON answers), GET /healthz, and the well-known files. Every answer is Cache-Control: no-store with Strict-Transport-Security: max-age=31536000, and /mcp allows any origin (its preflight offers POST and OPTIONS).

The same image speaks stdio when given the stdio entry, for catalogs that inspect a server that way:

docker run -i --rm -e UD_MCP_PROFILE=local uniquedomains-mcp-server dist/stdio.js

Development

npm ci
npm run build
npm test
npm run smoke

npm run generate rebuilds src/generated/tools.ts, openapi/v1.json and the tool list above from the API document that @uniquedomains/sdk ships; -- --check fails when they are out of date, -- --live compares the live document.
npm run smoke runs the MCP Inspector against both transports and a fixture API; -- --live uses the live API.
npm run plugin builds dist/chatgpt-plugin.zip from directories/openai/review.json (the review texts, the test cases, the release notes) and checks it against OpenAI's limits and categories; npm run plugin:test also builds a sheet marked as a placeholder.
npm run plugin:devin builds dist/devin/plugins/unique-domains/ (the manifest Devin's validator accepts, a 256 px logo and a copy of the skill) for a pull request to Devin's marketplace.
The nightly contract workflow opens its pull request with the workflow token, which needs the repository setting "Allow GitHub Actions to create and approve pull requests" (Settings, Actions, General).

License

MIT

mcp-server

Documentation