# HALOWERK Land Compare – Local Relief Comparison (Two Points)

> HALOWERK Land Compare – Local Relief Comparison (Two Points) is a paid API for AI agents from landvergleich.halowerk.com, paid per call via x402, $0.006/call, status unknown (last checked 2026-09-15).

Measures local relief for exactly two European coordinates and returns the signed difference and winner between the two locations.

## Facts

- Endpoint: POST https://landvergleich.halowerk.com/v1/compare-two-local-relief
- Price: $0.006/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/halowerk-land-compare-local-relief-comparison-two-points-f6b0bbec
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_B6Aicgy95wi-2159cMfF2

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability halowerk-land-compare-local-relief-comparison-two-points-f6b0bbec -d '<json body>'
```

Example prompt: Compare the local relief between Vienna, Austria (48.2082° N, 16.3738° E) and Zurich, Switzerland (47.3769° N, 8.5417° E) — which one has higher local terrain roughness and by how much?

## When to prefer this

Use this endpoint when you need a direct pairwise comparison of local relief (terrain roughness/variability) for exactly two European locations expressed as WGS84 coordinates. Prefer this over ranking endpoints when you only have two sites and want a clean signed difference and winner, rather than a multi-site ranked list.

## Known failure modes

- Coordinates outside European coverage bounds (lat 34–72.5, lon -31.5–40.5) return a validation error
- Fewer or more than exactly two locations in the array returns a schema validation error
- Invalid or malformed coordinate values (non-numeric) cause a 400 error
- Missing required longitude or latitude fields result in a validation error

## How this service works

Measures local relief for exactly two European coordinates with one method and reports the signed difference and winner where meaningful.

## Output

Returns the local relief measurements for both input coordinates, the signed numerical difference between them, and identifies which location has the higher local relief value where meaningful.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "locations": {
   "type": "array",
   "items": {
    "type": "object",
    "required": [
     "longitude",
     "latitude"
    ],
    "properties": {
     "name": {
      "type": "string",
      "maxLength": 60,
      "minLength": 1
     },
     "latitude": {
      "type": "number",
      "maximum": 72.5,
      "minimum": 34,
      "description": "WGS84 latitude inside the published European coverage."
     },
     "longitude": {
      "type": "number",
      "maximum": 40.5,
      "minimum": -31.5,
      "description": "WGS84 longitude inside the published European coverage."
     }
    },
    "additionalProperties": false
   },
   "maxItems": 2,
   "minItems": 2
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/halowerk-land-compare-local-relief-comparison-two-points-f6b0bbec/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from landvergleich.halowerk.com](https://www.zero.xyz/host/landvergleich.halowerk.com/llms.txt)