Danish addresses in Claude, Cursor and other AI tools with MCP

The Model Context Protocol (MCP) is a standard that lets an AI assistant call tools. With @danadresse/mcp-server, Claude, Cursor and other MCP clients can look up Danish addresses, clean them, find the nearest address to a coordinate, and fetch administrative areas and property data.

The server runs locally on your machine through npx and calls our API with your key. You need Node 18.17 or newer. If you would rather not install anything, use the hosted server at https://api.danadresse.dk/mcp (see below).

1. Create and test a key#

Create a live key under Keys. Do not use a test key or a domain-locked browser key. Both work for address lookups, but the tools for DAGI, property data, distance and quality score call /api/v1/enrich/…, and there they answer 403 (sandbox_scope or browser_key_scope).

Check the key before you configure the client:

curl -s "https://api.danadresse.dk/autocomplete?q=R%C3%A5dhuspladsen%201&per_side=1" \
  -H "X-Api-Key: $DANADRESSE_API_KEY"

2. Add the server to your client#

The server reads three environment variables:

Claude Desktop#

Edit claude_desktop_config.json. On macOS it is in ~/Library/Application Support/Claude/, on Windows in %APPDATA%\Claude\:

{
  "mcpServers": {
    "danadresse": {
      "command": "npx",
      "args": ["-y", "@danadresse/mcp-server"],
      "env": {
        "DANADRESSE_API_KEY": "dawa_live_your_key"
      }
    }
  }
}

Restart Claude Desktop. danadresse should now be listed among the tools.

Claude Code#

Add the server from the terminal:

claude mcp add danadresse \
  --env DANADRESSE_API_KEY=dawa_live_your_key \
  -- npx -y @danadresse/mcp-server

To share the setup with your team through the repository, put a .mcp.json in the project root. Claude Code fills in ${DANADRESSE_API_KEY} from the environment, so the key does not end up in Git:

{
  "mcpServers": {
    "danadresse": {
      "command": "npx",
      "args": ["-y", "@danadresse/mcp-server"],
      "env": {
        "DANADRESSE_API_KEY": "${DANADRESSE_API_KEY}"
      }
    }
  }
}

Cursor#

Put the configuration in ~/.cursor/mcp.json (for every project) or .cursor/mcp.json in a project:

{
  "mcpServers": {
    "danadresse": {
      "command": "npx",
      "args": ["-y", "@danadresse/mcp-server"],
      "env": {
        "DANADRESSE_API_KEY": "dawa_live_your_key"
      }
    }
  }
}

Other clients that support MCP over stdio work the same way: the command is npx -y @danadresse/mcp-server, and the key is passed as an environment variable.

Hosted server without installing anything#

If you do not have Node, or you use Claude.ai, ChatGPT or n8n, connect the client directly to our hosted MCP server at https://api.danadresse.dk/mcp. It uses Streamable HTTP and only answers POST. Sign in with your own key in X-Api-Key or Authorization: Bearer. Clients that cannot set headers (the connector screens in Claude.ai and ChatGPT) can put the key in the URL as ?api_key=. Create a separate key for that, so you can revoke it on its own.

In Claude Code:

claude mcp add --transport http danadresse https://api.danadresse.dk/mcp \
  --header "X-Api-Key: $DANADRESSE_API_KEY"

Check that the server answers with your key. tools/list does not count as a call:

curl -s -X POST "https://api.danadresse.dk/mcp" \
  -H "X-Api-Key: $DANADRESSE_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","id":1,"method":"tools/list"}'

The setup for Claude.ai, ChatGPT, Cursor, VS Code and n8n is on the AI page.

3. Know the tools#

The server gives the assistant eleven tools. The hosted server has the same ones plus a twelfth, quota_status, which shows the key's MCP and API usage this month:

enrich_with_dagi, property_data and distance_between need adgangsadresse ids. A suggestion from autocomplete_address is usually an adresse (with floor and door), and its adgangsadresse id is in data.adgangsadresseid. The assistant normally works this out, but mentioning it helps if it gets 404.

4. Know the MCP quota#

Calls from the MCP server have their own monthly quota, separate from the API quota. The server sends a User-Agent starting with danadresse-mcp, and that is what we count on. Calls through the hosted server count in the same quota:

On Hobby the MCP quota is a ceiling. After the quota and a grace buffer of 20 %, the API answers 429 quota_exceeded until next month, while your ordinary API calls carry on. One message to the assistant can lead to several tool calls, because it often searches first and then looks up or enriches.

The server retries 429, 502, 503 and 504 itself with backoff. If you still get errors, check usage in the dashboard.

5. Try it#

Example messages that use the tools:

Find the address Rådhuspladsen 1 in Copenhagen, and tell me which parish and police district it belongs to.

What is the nearest address to the GPS point 55.6761, 12.5683?

Clean this address from a CRM: "Raadhuspladsn 1, 1550 Kbh V". Is it safe enough to store?

How far is it in a straight line between Strandvejen 100, 2900 Hellerup and Rådhuspladsen 1, 1550 København V?

Which town has postcode 8000, and which municipality has code 0751?

The assistant picks the tools itself. In Claude Desktop and Claude Code you can see each call and its result before it is used in the answer.

Next steps#

• The MCP platform page: /integrationer/mcp.
• Keep an eye on the quota: Monitor usage.
• Change the key without downtime: Rotate API keys.