# HALOWERK Eastern Land – Croatia Soil Clay Fraction (0–5 cm)

> HALOWERK Eastern Land – Croatia Soil Clay Fraction (0–5 cm) is a paid API for AI agents from ostland.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 soil layer at a given coordinate, validated to fall within Croatia's boundary.

## Facts

- Endpoint: POST https://ostland.halowerk.com/v1/hr-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-eastern-land-croatia-soil-clay-fraction-0-5-cm-24fceff4
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_WDRlEyp6GU-aoaOh5vf4W

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-eastern-land-croatia-soil-clay-fraction-0-5-cm-24fceff4 -d '<json body>'
```

Example prompt: What's the mean clay fraction in the top 0–5 cm of soil at latitude 45.815, longitude 15.982 in Croatia?

## When to prefer this

Choose this endpoint when you need SoilGrids clay fraction data specifically for a point within Croatia and want geographic boundary validation enforced server-side. It is ideal for Croatian agricultural, environmental, or land-use applications where only Croatia-scoped data is relevant. If you need clay data for other European countries, look for sibling endpoints covering those boundaries.

## Known failure modes

- Coordinate outside Croatia's Natural Earth boundary — request rejected with a geographic validation error before any charge is incurred
- Latitude or longitude outside the European coverage range (lat 34–72.5, lon -31.5–40.5) — schema validation failure
- Missing latitude or longitude in request body — validation error
- Network or upstream SoilGrids data unavailability — service error response
- Malformed JSON payload — parse 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 Croatia; results outside it are rejected before payment.

## Output

A numeric value representing the mean clay fraction (typically expressed as g/kg or percentage) for the 0–5 cm topsoil layer at the queried coordinate, sourced from SoilGrids. Coordinates outside Croatia's boundary are rejected before the response is returned.

## 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-eastern-land-croatia-soil-clay-fraction-0-5-cm-24fceff4/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from ostland.halowerk.com](https://www.zero.xyz/host/ostland.halowerk.com/llms.txt)