# HALOWERK Southern Land – Portugal Terrain Ruggedness (Elevation Std Dev)

> HALOWERK Southern Land – Portugal Terrain Ruggedness (Elevation Std Dev) 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).

Returns the standard deviation of sampled surface elevations for a given WGS84 coordinate in Portugal, quantifying terrain ruggedness at that location.

## Facts

- Endpoint: POST https://suedland.halowerk.com/v1/pt-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-portugal-terrain-ruggedness-elevation-std-dev-614a5bf9
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_grrNBZyhVY9NklJ0_ybmW

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-portugal-terrain-ruggedness-elevation-std-dev-614a5bf9 -d '<json body>'
```

Example prompt: What's the terrain ruggedness score — the standard deviation of surface elevations — for the coordinate 37.8° latitude, -8.5° longitude in Portugal?

## When to prefer this

Choose this endpoint when you need a point-specific terrain ruggedness metric for a location in Portugal, particularly for land assessment, agricultural suitability, infrastructure planning, or ecological analysis. It is pre-validated against Portugal's official boundary, reducing the need for client-side geographic filtering. Prefer it over generic elevation APIs when you specifically need variability/ruggedness rather than raw elevation, and when your workflow is scoped to Portuguese territory.

## Known failure modes

- Coordinate outside Portugal's Natural Earth boundary — request rejected before payment is processed
- Latitude or longitude out of the published European coverage range (lat 34–72.5, lon -31.5–40.5) — validation error
- Malformed or missing coordinate fields — schema validation error
- Payment failure via x402 protocol — request not fulfilled

## How this service works

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

## Output

A numeric value representing the standard deviation of sampled surface elevations at the specified coordinate within Portugal. Higher values indicate more rugged, heterogeneous terrain; lower values indicate flat or uniform terrain. Returns an error or rejection if the coordinate falls outside the Natural Earth boundary for Portugal.

## 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-portugal-terrain-ruggedness-elevation-std-dev-614a5bf9/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)