Questions it answers
Check whether the domain for a startup, product or business name is already registered before you fall in love with it.
Ask "is acme.com available?", "check if this startup name is taken" or "find an available .com for my bakery name".
Startup Name Check turns a name into a domain label, then asks Cloudflare Registrar's domain-check API whether that domain can be registered and what it costs. When that API is not configured, or does not cover the ending, it asks the registry's public RDAP service instead.
It checks up to five names or domains at a time across .com, .net, .org, .ai, .app and .dev by default, or the endings you choose.
For a taken domain it shows the registration, expiry and last-change dates when the registry publishes them. It never returns who owns it or any contact details.
When Cloudflare Registrar answers for an available domain, the answer includes the registration and renewal cost. That figure is not a charge and does not reserve the name.
Results are indicative: they show the status at that moment and do not reserve a name. Premium or reserved names can be unavailable or cost more.
Trademarks are not searched, so run a trademark check before you commit to a name.
It stores nothing about you: answers are cached for up to five minutes, and the only lasting record is a daily count of calls per tool.
Short questions this server answers, each with a direct answer: Check if a startup name's domain is taken.
What it can do
- Checks whether a name's domain is registered in .com, .net, .org, .ai, .app and .dev
- Checks a full domain such as acme.com on its own
- Compares up to five candidate names in one answer
- Shows registration and expiry dates for domains that are taken, when the registry publishes them
- Shows the registration and renewal cost when Cloudflare Registrar returns one
- Never returns owner or contact details
Tools
check_domain_availability, Check name and domain availability. Use this when the user asks whether a domain or startup name is available or taken, for example "is acme.com available", "check if this startup name is taken" or "find an available .com for my bakery name". Pass up to 5 names or full domains. Names are checked across .com, .net, .org, .ai, .app and .dev unless tlds says otherwise. Returns, for each domain, available, registered (with registration, expiry and last-change dates when published), unsupported or unavailable, plus source. An available domain includes registrationCost and renewalCost when Cloudflare Registrar returns them. The result is indicative, not a reservation or a charge; it never includes owner details and does not check trademarks.
Add Startup Name Check in Pi
Pi does not speak MCP on its own. The pi-mcp-adapter extension (these steps match version 2.34.0) loads remote servers and keeps their schemas out of the prompt until you ask. Install it once, then restart Pi:
pi install npm:pi-mcp-adapterAdd the server to a shared MCP file. Use .mcp.json in the project if only that project needs Startup Name Check, or ~/.config/mcp/mcp.json if you want it in every project. Pi also reads ~/.agents/mcp.json. A Pi-only override lives in ~/.pi/agent/mcp.json or .pi/mcp.json and wins over the shared file.
{
"mcpServers": {
"names": {
"url": "https://names.openkrill.app/mcp",
"lifecycle": "eager"
}
}
}The url is enough. Do not set command: that field is for a local process. No API key header. lifecycle is eager so Pi connects at startup and can search tool names before the first call. A config that omits it still works: the first call connects. After restart, run /mcp and confirm the server is listed. Ask: Is acme.com available? The adapter should offer check_domain_availability.
Leave directTools off unless you want those schemas in every turn. With a handful of tools the cost is small. The default proxy is the better fit: search for the tool, then call it. /mcp disable names writes a project override in .pi/mcp.json without editing the shared file. Run /reload after that change.
Pi will not find this server by scanning Cursor or Claude config unless you run /mcp setup and import it. Putting the url in .mcp.json is the direct path and the one this page tests against. The server is the same public endpoint the other clients use, with the same limits and the same privacy rules.
If it does not work
The tool does not show up
Run /mcp to see the servers the adapter loaded. If it is missing, check the url entry in .mcp.json, then run /reload or restart Pi.
429 or rate_limited
Each server takes 60 calls a minute from one network, and some tools take fewer. Past that the call comes back as a tool error that starts with rate_limited: wait a minute and ask again. daily_limit means the server reached its shared daily cap, which resets at 00:00 UTC. A limit is not an answer, so do not read it as no results. For higher limits, ask support@openkrill.app for a key.
A call checked on 2026-10-17
example.com is a reserved public name, so the check is repeatable and does not probe a private brand. The request below was posted to https://names.openkrill.app/mcp as tools/call. HTTP 200. Source: the Startup Name Check server, read 2026-10-17.
{
"method": "tools/call",
"params": {
"name": "check_domain_availability",
"arguments": {
"names": [
"example.com"
]
}
}
}
- asOf. 2026-10-17
- notice. Indicative only: this is the status right now, it does not reserve anything, and premium or reserved names can be taken or cost more. A registration cost, when shown, is Cloudflare Registrar's figure and is not a charge.
- names. 1 returned
Repeat the call yourself if you need a newer reading. Cached answers expire. A rate limit is not a result: wait and try again. Nothing in the call is a ranking, a filing, or advice.
Using it in production
Nothing to install and nothing to run: no package, no Python or Node.js version and no environment variable. Startup Name Check runs on our servers, and your client only needs the URL https://names.openkrill.app/mcp.
| Rate limit | 60 tool calls a minute from one network. initialize and tools/list do not count. |
|---|---|
| Daily cap | 25000 tool calls a day per server, shared by every caller. It resets at 00:00 UTC. |
| At a limit | The call comes back as a tool error that starts with rate_limited (wait a minute) or daily_limit (try after 00:00 UTC), never as a partial answer. |
| Key | None. Do not add an Authorization header or a key field. |
| Higher limits | Email support@openkrill.app with the server name, the calls a day you expect and what they are for. We answer within 1 business day. |
| Freshness | Some answers come from a short cache. Each guide shows the date of its checked call; repeat a call when you need a newer reading. |
| Uptime | Scheduled test calls check the servers through the same endpoint. There is no SLA yet. |
| Data | What each server receives and keeps is on the privacy page. |
Use it in other apps
- Startup Name Check in ChatGPT
- Startup Name Check in Claude
- Startup Name Check in Cursor
- Startup Name Check in VS Code
Roles that use Startup Name Check
Frequently asked questions
How do I install the Startup Name Check MCP server in Pi?
Run pi install npm:pi-mcp-adapter once, add names with the url https://names.openkrill.app/mcp to .mcp.json, then restart Pi and run /mcp to see it.
Do I need an API key to run Startup Name Check in Pi?
No. This server takes no API key. For higher limits, email support@openkrill.app with the server name (Startup Name Check), the calls a day you expect and what they are for. We answer within 1 business day.
What should I do if Startup Name Check does not connect in Pi?
Check that the entry has a url and no command field, then run /reload or restart Pi and run /mcp.