# HALOWERK Nordic Land – Depression Depth (No-Depression Depth)

> HALOWERK Nordic Land – Depression Depth (No-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 difference between neighborhood mean elevation and center-point elevation (depression depth) for a coordinate in Norway.

## Facts

- Endpoint: POST https://nordland.halowerk.com/v1/no-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-depression-depth-no-depression-depth-faf8c2e0
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_mnE6pz-Xd4bNEes_7GB0v

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-depression-depth-no-depression-depth-faf8c2e0 -d '<json body>'
```

Example prompt: What's the topographic depression depth at latitude 59.91 and longitude 10.75 in Norway — specifically how much lower that point is compared to its surrounding neighborhood elevation?

## When to prefer this

Use this endpoint when you need a precise terrain depression metric (neighborhood mean minus center elevation) for a specific point in Norway. It is especially useful for hydrology, drainage analysis, flood risk modeling, or agricultural/infrastructure siting where low-lying terrain pockets matter. Prefer this over generic DEM lookup endpoints when you specifically need the depression depth (not raw elevation or slope) and your target is within Norway.

## Known failure modes

- Coordinate outside Norway boundary: request rejected before payment, error indicating coordinate is outside valid coverage area
- Coordinate within European coverage bounding box but outside Norway polygon: validation failure returned
- Latitude or longitude out of the published European bounding box range: schema validation error
- Location in Norway but with no available elevation data: may return null or error
- Network timeout or service unavailability: 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 Norway; results outside it are rejected before payment.

## Output

A numeric value representing the positive difference (in meters or terrain units) between the mean elevation of the surrounding neighborhood and the center-point elevation at the queried coordinate. If the center is higher than or equal to the neighborhood mean, the depth is zero. Coordinates outside the Norway 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-nordic-land-depression-depth-no-depression-depth-faf8c2e0/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)