check_domainsLABSCO SUMMARY
One tool, a hard cap of 50 domains, and a plain boolean per name.
The output is deliberately thin — registered or not, nothing about who owns it — which is what makes a brainstorm of fifty candidates readable in one response. Checks run sequentially at roughly 0.3 to 1 second per domain, with the WHOIS query timing out at 10 seconds, so a full batch takes a moment rather than being instant.
What it is
A single-purpose server that takes a list of domains and returns, for each one, whether it is registered.
What you get
- check_domains takes an array of domain names and returns a registered true/false per domain
- Two-way verification — WHOIS first, DNS as the fallback when the WHOIS query fails
- Internationalized domain names supported
- Input validated up front: no empty names, nothing over 255 characters, at most 50 domains per request
- Errors returned as messages you can act on rather than empty results
Requirements
A prebuilt binary from the releases page — chmod +x on Mac or Linux — and one entry in the client config pointing at it. No account, no key; it needs outbound network access for the WHOIS and DNS queries. A Python build is published separately as fastdomaincheck-mcp-server and runs under uvx.
Setup effort
Follow the published steps — chmod +x FastDomainCheck-MCP-Server
USE CASES
01
Filtering a brainstormed name list down to what is free
Send up to 50 candidates in one call and get a registered flag for each.
02
Checking one name across several extensions
Put every variant in the same request rather than looking them up one by one.
03
Trusting the result when WHOIS is being awkward
A failed WHOIS query falls through to DNS instead of returning nothing.
04
Checking a non-Latin domain
Internationalized names are handled directly, no punycode conversion on your side.
1 tool
Listed in project docs. Your client may show a different list.
BEFORE YOU INSTALL
What to know first
Tools you get
1 tool named in the project's documentation.
Requires
Network access for WHOIS and DNS queries
Where it runs
Both documented setups run the server on your machine.
INSTALLATION
Connect your client
Server setup
Download the archive for your platform from https://github.com/bingal/FastDomainCheck-MCP-Server/releases (for example FastDomainCheck-MCP-Server_1.0.4_darwin_arm64.tar.gz) and extract it
On Mac/Linux, make the binary executable:
TERMINAL
chmod +x FastDomainCheck-MCP-ServerMCP Clients
Claude Desktop — macOS, Linux
CLAUDE DESKTOP — MACOS, LINUX · JSON
{
"mcpServers": {
"fastdomaincheck": {
"command": "<YOUR_PATH_TO_FAST_DOMAIN_CHECK_MCP>",
"args": []
}
}
}<YOUR_PATH_TO_FAST_DOMAIN_CHECK_MCP> is the absolute path to the extracted binary.
Claude Desktop — Windows
CLAUDE DESKTOP — WINDOWS · JSON
{
"mcpServers": {
"fastdomaincheck": {
"command": "<YOUR_PATH_TO_FAST_DOMAIN_CHECK_MCP>",
"args": []
}
}
}<YOUR_PATH_TO_FAST_DOMAIN_CHECK_MCP> is the full path to the extracted .exe.
