Publicdata Kr MCP server

FieldCure MCP PublicData.Kr

Korean public data API gateway. A Model Context Protocol (MCP) server that lets any MCP client discover, inspect, and call 80,000+ APIs on data.go.kr — weather, real estate, business registration, air quality, transit, and more. Built with C# and the official MCP C# SDK.

Features

• 3 tools — search APIs by keyword, inspect parameters/response fields, call any data.go.kr API
• Automatic serviceKey injection — the API key is added to every request; never leaked to the LLM
• Lazy key resolution — env var → MCP Elicitation → soft-fail chain (no hard-fail on startup). Hosts that support MCP Elicitation can prompt the user for the key on first use; on upstream 401/403 or SERVICEKEYISNOTREGISTERED the cached key is invalidated and a re-elicit is attempted (session cap: 2 re-elicits)
• XML → JSON normalization — strips the response/header/body/items wrapper, returns clean JSON
• Error code mapping — translates data.go.kr error codes into Korean guidance messages the LLM can relay directly
• SSRF protection — domain whitelist limits calls to approved government hosts
• EUC-KR support — legacy encoding from older government APIs is auto-detected and converted
• Stateless — no cache, no database, no local files; every call is independent
• Stdio transport — standard MCP subprocess model via JSON-RPC over stdin/stdout

Installation

dotnet tool (recommended)

dotnet tool install -g FieldCure.Mcp.PublicData.Kr

After installation, the fieldcure-mcp-publicdata-kr command is available globally.

From source

git clone https://github.com/fieldcure/fieldcure-mcp-publicdata.git
cd fieldcure-mcp-publicdata
dotnet build

Prerequisites

(data.go.kr 회원가입 후 인증키 발급)

1. Sign up at data.go.kr and get your API key

— discoverapi and describeapi depend on this API (discoverapi, describeapi 도구가 이 API를 사용합니다)

1. Subscribe to 목록조회서비스 (Required)

(조회하려는 개별 API도 각각 활용신청 필요)

1. Subscribe to each individual API you want to query

Requirements

• .NET 8.0 Runtime or later

Authentication

This server requires a data.go.kr API key (공공데이터포털 인증키). Key resolution is lazy (on first tool call) and follows the FieldCure MCP Credential ADR:

on the first tool call (requires a client that supports MCP Elicitation — e.g. Claude Code ≥ 2.1.76, AssistStudio). The resolved key is cached in process memory for the session lifetime and is never written to disk by the server.

1. Environment variable — DATAGOKRAPIKEY (canonical) or PUBLICDATAAPIKEY (legacy alias)
2. MCP Elicitation — if no env var is found, the server requests the key interactively

structured error message asking the user to set the env var.

1. Soft-fail — if both paths fail, tools/list still works and tool calls return a

--api-key is also accepted as a CLI arg but is intended for manual testing only, not as a supported configuration path.

Setup by host

Claude Code / Claude Desktop — add the key to your MCP config:

{
  "mcpServers": {
    "publicdata-kr": {
      "command": "fieldcure-mcp-publicdata-kr",
      "env": {
        "DATA_GO_KR_API_KEY": "<your-key>"
      }
    }
  }
}

Shortened. The full README is on GitHub.