# HALOWERK Baltic Land – Depression Depth

> HALOWERK Baltic Land – Depression Depth is a paid API for AI agents from baltikum.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, indicating topographic depression depth at a given coordinate in Germany.

## Facts

- Endpoint: POST https://baltikum.halowerk.com/v1/de-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-baltic-land-depression-depth-3c627f15
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Cs_Rt4zURC3lhemojQb2k

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-baltic-land-depression-depth-3c627f15 -d '<json body>'
```

Example prompt: What's the topographic depression depth at latitude 51.34, longitude 9.87 in Germany — how much lower is that point compared to its surrounding neighborhood elevation?

## When to prefer this

Choose this endpoint when you need a precise, point-level measure of topographic depression depth (neighborhood mean minus center elevation) for a specific coordinate within Germany. It is ideal for hydrology, flood risk, drainage analysis, and terrain characterization workflows where understanding local surface lows matters. It differs from general elevation lookup (which returns absolute height) or slope/gradient endpoints (which measure steepness rather than sinks).

## Known failure modes

- Coordinate outside Germany boundary returns a rejection error before payment is processed
- Latitude or longitude outside the published European coverage range (lat 34–72.5, lon -31.5–40.5) is rejected at input validation
- Invalid or missing coordinate fields return a schema validation error
- Ambiguous coordinates on the boundary may be rejected due to strict Natural Earth polygon matching

## How this service works

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

## Output

A numeric value representing the positive elevation difference (in meters) between the mean elevation of the surrounding neighborhood cells and the center cell elevation, indicating how deep a topographic depression is at the queried point. Returns an error if the coordinate falls outside the validated Germany boundary.

## 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-baltic-land-depression-depth-3c627f15/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from baltikum.halowerk.com](https://www.zero.xyz/host/baltikum.halowerk.com/llms.txt)