e-Stat API Search MCP Server

This is a Model Context Protocol (MCP) server that runs on Cloudflare Workers and provides an interface to the e-Stat API (Official Statistics of Japan).

It allows AI agents (like Claude Desktop) to search for Japanese government statistical tables, inspect metadata, and retrieve statistical data for analysis.

Features

• Search Tables (get_tables): Find statistical tables by keywords, ministry code, or category.
• Search Surveys (get_surveys): Find available surveys if you are unsure about specific tables.
• Get Metadata (get_metadata): Retrieve detailed metadata (classifications, area codes, time periods) for a specific table.
• Get Data (get_data): Fetch the actual statistical data values based on the table ID and optional filters.

Prerequisites

• Node.js: (v18 or later recommended)
• Cloudflare Wrangler: CLI tool for Cloudflare Workers.
• e-Stat API Key: You must register to get an "Application ID" (appId).
  • Register for e-Stat API

Setup

1. Clone the repository

2. Install dependencies

   npm install

3. Configure Environment Variables This server requires the ESTAT_API_KEY environment variable.

   For Local Development: Create a .dev.vars file in the project root:

   ESTAT_API_KEY=your_app_id_here
   

   For Production (Cloudflare Deployment): Set the secret using Wrangler:

   npx wrangler secret put ESTAT_API_KEY
   # Enter your App ID when prompted

Usage

Local Development

To run the MCP server locally for testing:

npm run dev

This will start the server at http://localhost:8787.

Deployment

To deploy to your Cloudflare Workers account:

npm run deploy

Connecting to Claude Desktop

To use this MCP server with Claude Desktop, add the following configuration to your Claude Desktop config file:

• macOS: ~/Library/Application Support/Claude/claude_desktop_config.json
• Windows: %APPDATA%\Claude\claude_desktop_config.json

Configuration:

{
  "mcpServers": {
    "e-stat-search": {
      "command": "npx",
      "args": [
        "-y",
        "@modelcontextprotocol/server-cloudflare",
        "start",
        "https://<your-worker-name>.<your-subdomain>.workers.dev"
      ]
    }
  }
}

Note: Replace the URL with your deployed Cloudflare Worker URL, or use http://localhost:8787 if running locally along with mcp-remote.

Alternatively, if you are running locally and want to connect directly:

{
  "mcpServers": {
    "e-stat-local": {
      "command": "npx",
      "args": [
        "mcp-remote",
        "http://localhost:8787/sse"
      ]
    }
  }
}

Tools Available

get_tables

Searches for statistical tables.

• Parameters: searchWord, statsCode, limit, etc.

get_surveys

Searches for surveys. Useful for data discovery.

• Parameters: searchWord, limit, etc.

get_metadata

Retrieves structure and classification information for a table.

• Parameters: statsDataId (Required).

get_data

Fetches the actual data records.

• Parameters: statsDataId (Required), and optional filters like cdCat01, cdTime, cdArea.