# HALOWERK Baltic Land – Poland Soil Clay Fraction (0-5 cm)

> HALOWERK Baltic Land – Poland Soil Clay Fraction (0-5 cm) is a paid API for AI agents from baltikum.halowerk.com, paid per call via x402, $0.004/call, status unknown (last checked 2026-09-15).

Returns the mean SoilGrids clay fraction for the 0–5 cm topsoil layer at a given coordinate within Poland, validated against the Natural Earth Poland boundary.

## Facts

- Endpoint: POST https://baltikum.halowerk.com/v1/pl-soil-clay
- Price: $0.004/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-poland-soil-clay-fraction-0-5-cm-e1ffe6bd
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_67lK2u5mHoeVURg-vo-UY

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-poland-soil-clay-fraction-0-5-cm-e1ffe6bd -d '<json body>'
```

Example prompt: What's the SoilGrids clay fraction in the top 5 cm of soil at latitude 52.2297 and longitude 21.0122 in Poland?

## When to prefer this

Use this endpoint when you need point-level clay fraction data specifically for Poland from the SoilGrids dataset, especially in workflows involving soil texture classification, agricultural planning, environmental assessment, or construction ground surveys. Prefer this over general geospatial APIs when you need a pre-validated, pay-per-call, boundary-checked soil property lookup with no authentication setup required.

## Known failure modes

- Coordinate outside Poland's Natural Earth boundary — request rejected before payment, returns a boundary validation error
- Latitude or longitude out of the published European coverage range (lat 34–72.5, lon -31.5–40.5) — schema validation error
- Invalid or missing coordinate values — request rejected with input validation error
- Service unavailable or upstream SoilGrids data unreachable — returns a server error

## How this service works

Mean SoilGrids clay fraction for the 0-5 cm layer. The coordinate is validated against the Natural Earth boundary for Poland; results outside it are rejected before payment.

## Output

A numeric value representing the mean clay fraction (likely as a percentage or volumetric fraction) in the 0–5 cm soil layer at the specified coordinate, sourced from SoilGrids. Coordinates outside Poland's Natural Earth boundary are rejected before the 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-baltic-land-poland-soil-clay-fraction-0-5-cm-e1ffe6bd/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)