# HALOWERK Nordic Land — Denmark Depression Depth

> HALOWERK Nordic Land — Denmark Depression Depth is a paid API for AI agents from nordland.halowerk.com, paid per call via x402, $0.003/call, status unknown (last checked 2026-09-15).

Returns the positive elevation difference between a neighborhood mean and the center cell elevation, quantifying topographic depression depth at a given coordinate in Denmark.

## Facts

- Endpoint: POST https://nordland.halowerk.com/v1/dk-depression-depth
- 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-nordic-land-denmark-depression-depth-faebd0b9
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_kL2LeYeHDcbwVI_hHbzM4

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-denmark-depression-depth-faebd0b9 -d '<json body>'
```

Example prompt: What's the depression depth at latitude 55.676 and longitude 12.568 in Denmark — how much lower is that point compared to its surrounding neighborhood elevation?

## When to prefer this

Choose this endpoint when you need a precise, per-point topographic depression depth metric specifically for locations within Denmark, particularly for hydrology, flood-risk, drainage, or land-use applications. It is preferable over general elevation APIs because it computes the neighborhood-mean-minus-center-elevation metric directly, saving local raster processing. The pre-payment boundary validation means you won't be charged for out-of-scope coordinates.

## Known failure modes

- Coordinate outside Denmark's Natural Earth boundary — request rejected before payment, no result returned
- Latitude or longitude outside the published European coverage range (lat 34–72.5, lon -31.5–40.5) — validation error
- Malformed or missing coordinate parameters — input schema validation failure
- Point within European bounds but outside Denmark polygon — boundary rejection
- Service unavailability or timeout — HTTP 5xx error

## How this service works

Positive difference between the neighborhood mean and center elevation. The coordinate is validated against the Natural Earth boundary for Denmark; results outside it are rejected before payment.

## Output

A numeric value representing the positive elevation difference (in meters) between the neighborhood mean surface elevation and the center cell elevation, indicating how much of a topographic depression exists at the queried point. Coordinates outside Denmark'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-denmark-depression-depth-faebd0b9/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)