# HALOWERK Central Land – Slovakia Mean Slope

> HALOWERK Central Land – Slovakia Mean Slope is a paid API for AI agents from mitteleuropa.halowerk.com, paid per call via x402, $0.003/call, status unknown (last checked 2026-09-13).

Returns the mean first-order surface gradient (slope) computed across a local analysis grid for a given WGS84 coordinate within Slovakia.

## Facts

- Endpoint: POST https://mitteleuropa.halowerk.com/v1/sk-mean-slope
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/halowerk-central-land-slovakia-mean-slope-61f9c33f
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_U0s3Iy3tELPMGiTmy2rKc

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-central-land-slovakia-mean-slope-61f9c33f -d '<json body>'
```

Example prompt: What's the mean surface slope at latitude 48.7, longitude 19.1 in Slovakia? I need the first-order terrain gradient for that location.

## When to prefer this

Choose this endpoint when you need mean surface slope (terrain gradient) specifically for a point within Slovakia. It validates coordinates against the Natural Earth Slovakia boundary before processing, ensuring accurate regional scoping. Prefer it over generic DEM tools when you need a ready-computed gradient statistic rather than raw elevation data, and when Slovakia is the area of interest.

## Known failure modes

- Coordinate outside Slovakia boundary — request rejected before payment with a validation error
- Coordinate outside European coverage range (lat 34–72.5, lon -31.5–40.5) — rejected as out of bounds
- Invalid or missing latitude/longitude fields — schema validation error
- Service unavailability — HTTP 5xx error

## How this service works

Mean first-order surface gradient across the analysis grid. The coordinate is validated against the Natural Earth boundary for Slovakia; results outside it are rejected before payment.

## Output

A numeric value representing the mean first-order surface gradient (slope) across the analysis grid centered on the provided coordinate. Coordinates outside the Slovakia boundary are rejected before any computation or payment is processed.

## 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-central-land-slovakia-mean-slope-61f9c33f/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from mitteleuropa.halowerk.com](https://www.zero.xyz/host/mitteleuropa.halowerk.com/llms.txt)