# HALOWERK Southern Land – Spain Terrain Ruggedness Index

> HALOWERK Southern Land – Spain Terrain Ruggedness Index is a paid API for AI agents from suedland.halowerk.com, paid per call via x402, $0.003/call, status unknown (last checked 2026-09-15).

Computes the standard deviation of sampled surface elevations (terrain ruggedness) for a given WGS84 coordinate within Spain, validated against Natural Earth boundaries.

## Facts

- Endpoint: POST https://suedland.halowerk.com/v1/es-ruggedness
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/halowerk-southern-land-spain-terrain-ruggedness-index-2be284a6
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_RGagInvK6aTU5U9VuYoHe

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-southern-land-spain-terrain-ruggedness-index-2be284a6 -d '<json body>'
```

Example prompt: What's the terrain ruggedness at latitude 40.4168, longitude -3.7038 in Spain — give me the standard deviation of surface elevations for that spot.

## When to prefer this

Choose this endpoint when you need a quantitative measure of terrain roughness or surface elevation variability for a specific point in Spain, especially for applications like land suitability analysis, infrastructure planning, agricultural screening, or ecological modeling. It is preferred over generic elevation lookup endpoints because it returns a statistical variability metric (standard deviation) rather than a single elevation value, and it strictly validates inputs against Spain's boundary before charging.

## Known failure modes

- Coordinate outside Spain boundary — request rejected before payment with a validation error
- Latitude or longitude out of published European coverage range (34–72.5°N, -31.5–40.5°E) — schema validation failure
- Malformed or missing latitude/longitude fields — input validation error
- Service unavailable or upstream elevation data temporarily inaccessible — HTTP 5xx error

## How this service works

Standard deviation of sampled surface elevations. The coordinate is validated against the Natural Earth boundary for Spain; results outside it are rejected before payment.

## Output

Returns a numeric value representing the standard deviation of sampled surface elevations at the requested coordinate, indicating how rugged or variable the terrain is. Coordinates outside the Natural Earth boundary for Spain are rejected before processing or payment is charged.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "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."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/halowerk-southern-land-spain-terrain-ruggedness-index-2be284a6/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from suedland.halowerk.com](https://www.zero.xyz/host/suedland.halowerk.com/llms.txt)