# HALOWERK Southern Land – PT Depression Depth

> HALOWERK Southern Land – PT Depression Depth 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 positive difference between neighborhood mean elevation and center-point elevation for a given coordinate within Portugal, measuring topographic depression depth.

## Facts

- Endpoint: POST https://suedland.halowerk.com/v1/pt-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-southern-land-pt-depression-depth-dd498bd1
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_VeMbZ9ZeUp0lZn99jmwjL

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-pt-depression-depth-dd498bd1 -d '<json body>'
```

Example prompt: Can you get the topographic depression depth for the coordinates 38.7169° N, 9.1395° W in Portugal — I need to know how much lower that point is compared to its surrounding neighborhood elevation?

## When to prefer this

Use this endpoint when you need a precise, per-point measure of terrain concavity or hollow depth specifically within Portugal. It is ideal for agricultural site assessment, hydrological modelling, drainage analysis, or land evaluation tasks where knowing how depressed a point is relative to its neighbors matters. Prefer this over generic DEM APIs when you need boundary-validated, pay-per-query elevation depression data restricted to Portugal.

## Known failure modes

- Coordinate outside Portugal boundary — request rejected before payment, returns validation error
- Latitude or longitude outside the European coverage bounding box (lat 34–72.5, lon -31.5–40.5) — schema validation failure
- No elevation data available for the queried cell — returns data-not-found error
- Depression value is zero or negative (i.e. location is not a depression) — may return 0 or null
- Network or payment processing failure via x402 protocol

## How this service works

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

## Output

A numeric value representing the positive elevation difference (in metres) between the mean elevation of the surrounding neighborhood cells and the center-point elevation, indicating how depressed the location is relative to its local terrain. Coordinates outside the Portugal boundary are rejected before any charge is incurred.

## 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-pt-depression-depth-dd498bd1/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)