# HALOWERK Nordic Land – Sweden Maximum Surface Slope

> HALOWERK Nordic Land – Sweden Maximum Surface Slope is a paid API for AI agents from nordland.halowerk.com, paid per call via x402, $0.003/call, status unknown (last checked 2026-09-14).

Returns the maximum adjacent-cell surface gradient (slope) for a given coordinate within Sweden's boundary, computed across an analysis grid.

## Facts

- Endpoint: POST https://nordland.halowerk.com/v1/se-max-slope
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/halowerk-nordic-land-sweden-maximum-surface-slope-bffa67b8
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Z8BEmuLEevxsup9OCbAm4

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-nordic-land-sweden-maximum-surface-slope-bffa67b8 -d '<json body>'
```

Example prompt: What's the maximum surface slope at latitude 59.33, longitude 18.07 in Sweden? I need the steepest adjacent-cell gradient across the analysis grid for that location.

## When to prefer this

Choose this endpoint when you need maximum surface slope (steepest adjacent-cell gradient) specifically for a coordinate within Sweden, validated against the Natural Earth Sweden boundary. Prefer it over generic elevation APIs when you need pre-computed terrain gradient rather than raw elevation, and when Sweden-specific boundary validation and pay-per-call pricing ($0.003 USDC) are acceptable.

## Known failure modes

- Coordinate outside Sweden's Natural Earth boundary — request rejected, no charge incurred
- Latitude or longitude out of the published European coverage range (lat 34–72.5, lon -31.5–40.5) — validation error
- Missing required latitude or longitude fields — schema validation error
- Payment failure via x402 protocol — request not processed

## How this service works

Maximum adjacent-cell surface gradient across the analysis grid. The coordinate is validated against the Natural Earth boundary for Sweden; results outside it are rejected before payment.

## Output

A numeric value representing the maximum adjacent-cell surface gradient (slope) computed across the analysis grid for the validated Swedish coordinate. Coordinates outside Sweden's Natural Earth boundary are rejected before any charge is applied.

## 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-nordic-land-sweden-maximum-surface-slope-bffa67b8/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from nordland.halowerk.com](https://www.zero.xyz/host/nordland.halowerk.com/llms.txt)