# zweitwohnungsteuer_changes

List German cities that changed (raised or newly introduced) their Zweitwohnungsteuer in a given year — the fresh-news angle. Defaults to 2026 (Stuttgart, Chemnitz, Heidelberg doubled to 20%, etc.).

Agent View of the PolicyLayer registry record for `zweitwohnungsteuer_changes`. HTML page: https://policylayer.com/tools/dev-crelvo-german-tax-data/zweitwohnungsteuer-changes

## Facts

- Tool: `zweitwohnungsteuer_changes`
- Server: German Tax Data (`https://data.crelvo.dev/mcp`) — https://policylayer.com/tools/dev-crelvo-german-tax-data.md
- Homepage: https://github.com/https://data.crelvo.dev/mcp
- Risk category: Read (Low risk)
- Registry record: grade C, identity unverified
- Server auth posture: open
- Server rate-limited: no
- Parameters: 1
- Recommended policy verdict: Allowed

## Parameters

| Parameter | Type | Required | Description |
| --- | --- | --- | --- |
| `year` | integer | no |  |

Parameters from the server's own tool schema.

## Example call (MCP tools/call, JSON-RPC 2.0)

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "zweitwohnungsteuer_changes",
    "arguments": {}
  }
}
```

## Why zweitwohnungsteuer_changes is rated Low

This tool queries and retrieves historical tax policy change data from a database. It performs a read-only lookup operation to surface information about municipal tax rate changes. There is no modification, deletion, execution of code, or financial operation involved. The tool simply surfaces publicly available tax policy information cited to source.

From the tool's own definition: "Tool name 'zweitwohnungsteuer_changes' and description 'List German cities that changed... their Zweitwohnungsteuer in a given year' — the verb 'List' indicates data retrieval with no side effects."

## Use case

AI agents call zweitwohnungsteuer_changes to retrieve information from German Tax Data without modifying anything. It is typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.

## Recommended policy (PolicyLayer)

Verdict: **Allowed**. Enforced by the PolicyLayer MCP gateway (https://policylayer.com/mcp-gateway) before a call reaches German Tax Data:

```json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "zweitwohnungsteuer_changes": {}
  }
}
```

## Other tools on German Tax Data (8)

- `hundesteuer_by_state` — Read — https://policylayer.com/tools/dev-crelvo-german-tax-data/hundesteuer-by-state.md
- `hundesteuer_lookup` — Read — https://policylayer.com/tools/dev-crelvo-german-tax-data/hundesteuer-lookup.md
- `hundesteuer_ranking` — Read — https://policylayer.com/tools/dev-crelvo-german-tax-data/hundesteuer-ranking.md
- `list_datasets` — Read — https://policylayer.com/tools/dev-crelvo-german-tax-data/list-datasets.md
- `pfaendung_calc` — Read — https://policylayer.com/tools/dev-crelvo-german-tax-data/pfaendung-calc.md
- `zweitwohnungsteuer_by_state` — Read — https://policylayer.com/tools/dev-crelvo-german-tax-data/zweitwohnungsteuer-by-state.md
- `zweitwohnungsteuer_lookup` — Read — https://policylayer.com/tools/dev-crelvo-german-tax-data/zweitwohnungsteuer-lookup.md
- `zweitwohnungsteuer_ranking` — Read — https://policylayer.com/tools/dev-crelvo-german-tax-data/zweitwohnungsteuer-ranking.md

## For agents

This record is a snapshot. Live verdicts and the full registry:

- Check every server in your MCP config at once: `npx -y policylayer stack`
- Vet a server before you add it: install the mcp-precheck skill — `npx skills add https://policylayer.com` (skill text: https://policylayer.com/skill.md)
- Query the registry over MCP: endpoint `https://api.policylayer.com/mcp` — tools `check_mcp_server`, `check_mcp_stack`, `check_tool`, `search_registry`, `get_change_events`

---

Source: the PolicyLayer MCP registry — one continuously verified record per MCP server. Full record: https://policylayer.com/registry?q=dev-crelvo-german-tax-data · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/dev-crelvo-german-tax-data