Reference Data MCP Server runs on your own machine — the client starts it, so there is no endpoint to ping. 104 installs a week from npm. Last commit 25 Aug 2026.
Countries, timezones, elements, constants, HTTP status codes, unit conversion, and MIME type lookup.
Nothing serious here today
Today is the operative word: we check Reference Data MCP Server every 15 minutes and re-read its code on every release. Watch it and you find out the day that stops being true.
Connect this server
This server runs on your own machine — install it with the package manager and the client starts it for you. Package name taken from the official registry entry.
claude mcp add reference-data-mcp-server -- npx -y @cyanheads/reference-data-mcp-server{
"mcpServers": {
"reference-data-mcp-server": {
"args": [
"-y",
"@cyanheads/reference-data-mcp-server"
],
"command": "npx"
}
}
}[mcp_servers.reference-data-mcp-server]
command = "npx"
args = ["-y", "@cyanheads/reference-data-mcp-server"]{
"mcpServers": {
"reference-data-mcp-server": {
"args": [
"-y",
"@cyanheads/reference-data-mcp-server"
],
"command": "npx"
}
}
}{
"mcpServers": {
"reference-data-mcp-server": {
"args": [
"-y",
"@cyanheads/reference-data-mcp-server"
],
"command": "npx"
}
}
}This one needs environment variables set before it will start:
MCP_HTTP_HOST (The hostname for the HTTP server.), MCP_HTTP_PORT (The port to run the HTTP server on.), MCP_HTTP_ENDPOINT_PATH (The endpoint path for the MCP server.), MCP_AUTH_MODE (Authentication mode to use: 'none', 'jwt', or 'oauth'.), MCP_LOG_LEVEL (Sets the minimum log level for output (e.g., 'debug', 'info', 'warn').).
The author declared them in the registry entry; get the values from the project itself.
Alternatives to Reference Data MCP Server
same job, measured the same wayPostal code lookup with place names and coordinates for 60+ countries. Via Zippopotam.us.
Chữ Nôm lookup, search and Vietnamese ↔ Nôm conversion, incl. 2,422 unmapped PUA codepoints.
Short catalog of common HTTP status codes.
Timen time tracking — timers, time entries, reports, projects, and clients.
Real-time codebase graph for AI assistants: call graphs, dependencies, symbol lookup.
Create choropleth, category and pin maps of countries, states, counties and ZIP codes as images.
Free, keyless postal/ZIP code lookup: place name(s), state/region, and coordinates.
MCP server for Twilio — global SMS, WhatsApp, Voice, Verify, and Lookup across 180+ countries
Reference Data MCP Server — questions
Answers built from our own checks of this server.