japan-data-mcp — Claude Code MCP server: what it does, how to install
Connects AI assistants to official Japanese open data, covering e-Stat metrics, corporate registries, and property sales. Useful for regional comparisons across municipalities.
claude mcp add japan-data-mcp -e ESTAT_APP_ID=<ESTAT_APP_ID> -e CORP_APP_ID=<CORP_APP_ID> -e REALESTATE_API_KEY=<REALESTATE_API_KEY> -- uvx japan-data-mcpWhat japan-data-mcp does
The server queries four official public sources in Japan: e-Stat, the Corporate Number system, invoice registration records, and property market datasets. It automatically resolves numeric administrative codes such as 13000 into readable names for Tokyo and surrounding areas. Coverage spans 47 prefectures and roughly 1,700 cities and towns.
Without the ESTAT_APP_ID environment variable, the server will not launch at all. That single credential is required, though registration is free. Corporate API access takes two to four weeks to obtain, but statistical tools work without it. Pre-built functions like get_population and compare_regions return pivot-ready tables with explicit source timestamps.
What it helps with
- compare population statistics across multiple Japanese municipalities
- look up corporate numbers and registered details by company name
- check invoice registration validity on a specific date
- retrieve residential transaction prices and market summaries
Example prompts for the agent
- Compare the population of Sapporo, Sendai, and Fukuoka using
compare_regions - Look up corporate details for Toyota in Aichi prefecture with
search_corporations - Verify invoice registration status using
check_invoice_registration
How to install japan-data-mcp
Platform CLI
claude mcp add japan-data-mcp -e ESTAT_APP_ID=<ESTAT_APP_ID> -e CORP_APP_ID=<CORP_APP_ID> -e REALESTATE_API_KEY=<REALESTATE_API_KEY> -- uvx japan-data-mcpReplace <…> with your own values. uvx runs the command named after the package; if the README names another one, use uvx --from japan-data-mcp <command>
Platform CLI
codex mcp add japan-data-mcp --env ESTAT_APP_ID=<ESTAT_APP_ID> --env CORP_APP_ID=<CORP_APP_ID> --env REALESTATE_API_KEY=<REALESTATE_API_KEY> -- uvx japan-data-mcpReplace <…> with your own values. uvx runs the command named after the package; if the README names another one, use uvx --from japan-data-mcp <command>
Config file
{
"mcpServers": {
"japan-data-mcp": {
"command": "uvx",
"args": [
"japan-data-mcp"
],
"env": {
"ESTAT_APP_ID": "<ESTAT_APP_ID>",
"CORP_APP_ID": "<CORP_APP_ID>",
"REALESTATE_API_KEY": "<REALESTATE_API_KEY>"
}
}
}
}Replace <…> with your own values. uvx runs the command named after the package; if the README names another one, use uvx --from japan-data-mcp <command>
Config file
{
"servers": {
"japan-data-mcp": {
"type": "stdio",
"command": "uvx",
"args": [
"japan-data-mcp"
],
"env": {
"ESTAT_APP_ID": "<ESTAT_APP_ID>",
"CORP_APP_ID": "<CORP_APP_ID>",
"REALESTATE_API_KEY": "<REALESTATE_API_KEY>"
}
}
}
}Replace <…> with your own values. uvx runs the command named after the package; if the README names another one, use uvx --from japan-data-mcp <command>
Platform CLI
gemini mcp add -e ESTAT_APP_ID=<ESTAT_APP_ID> -e CORP_APP_ID=<CORP_APP_ID> -e REALESTATE_API_KEY=<REALESTATE_API_KEY> japan-data-mcp uvx japan-data-mcpReplace <…> with your own values. uvx runs the command named after the package; if the README names another one, use uvx --from japan-data-mcp <command>
Step by step, with commands for each platform: How to add an MCP server to Claude Code, Codex, Cursor, VS Code, Gemini CLI and more
Questions about japan-data-mcp
How do I install japan-data-mcp in Claude Code?
Run `claude mcp add japan-data-mcp -e ESTAT_APP_ID=<ESTAT_APP_ID> -e CORP_APP_ID=<CORP_APP_ID> -e REALESTATE_API_KEY=<REALESTATE_API_KEY> -- uvx japan-data-mcp. Only ESTAT_APP_ID` is strictly required to start the server.
What does japan-data-mcp do?
It queries Japanese open statistical data, corporate registry listings, and real estate sales directly from your coding assistant. Returned records include source references and retrieval dates.
Are all API credentials required before running the server?
No, only the ESTAT_APP_ID variable is mandatory. Corporate and real estate API credentials can remain unset if you only need demographic and regional statistics.
