# HALOWERK Baltic Land – Local Relief (Poland)

> HALOWERK Baltic Land – Local Relief (Poland) 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 local surface relief (difference between maximum and minimum sampled elevation) for a coordinate point within Poland.

## Facts

- Endpoint: POST https://baltikum.halowerk.com/v1/pl-local-relief
- 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-local-relief-poland-9e9a44d4
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Zsx3bAp98sH9UCJbzz2h3

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-local-relief-poland-9e9a44d4 -d '<json body>'
```

Example prompt: What's the local surface relief — the difference between the highest and lowest nearby elevations — at 52.2297° N, 21.0122° E in Poland?

## When to prefer this

Use this endpoint when you need point-level local terrain relief specifically within Poland, validated against official boundaries. It is ideal for geospatial enrichment pipelines, land assessment tools, or any agent workflow that needs a quick, pay-per-call terrain roughness metric without standing up your own DEM analysis. Prefer it over general-purpose elevation APIs when you need the relief range (max minus min) rather than absolute elevation, and when your coordinates are confirmed to be within Poland.

## Known failure modes

- Coordinate outside Poland boundary: request rejected before payment with a validation error
- Coordinate within European coverage but outside Poland: rejected by Natural Earth boundary check
- Malformed latitude/longitude (out of range): 400-level validation error
- Latitude or longitude missing from request body: schema validation failure
- Service temporarily unavailable: 5xx error with no relief value returned

## How this service works

Difference between maximum and minimum sampled surface elevation. The coordinate is validated against the Natural Earth boundary for Poland; results outside it are rejected before payment.

## Output

A numeric value representing the local relief in meters — the difference between the maximum and minimum sampled surface elevation within the analysis grid centered on the queried coordinate. Coordinates outside Poland's boundary are rejected before processing.

## 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-local-relief-poland-9e9a44d4/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)