# HALOWERK Eastern Land – Croatia Soil Organic Carbon (0-5 cm)

> HALOWERK Eastern Land – Croatia Soil Organic Carbon (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 mean SoilGrids organic carbon content for the 0-5 cm soil layer at a given WGS84 coordinate within Croatia's boundaries.

## Facts

- Endpoint: POST https://ostland.halowerk.com/v1/hr-soil-organic-carbon
- 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-organic-carbon-0-5-cm-a8599f4e
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_1I727xH7OueoUtMn6BY-X

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-organic-carbon-0-5-cm-a8599f4e -d '<json body>'
```

Example prompt: What's the mean soil organic carbon content in the top 5 cm of soil at latitude 45.3 and longitude 16.8 in Croatia?

## When to prefer this

Choose this endpoint when you need point-level SoilGrids organic carbon data specifically for locations within Croatia and want built-in boundary validation to avoid charges for out-of-area coordinates. Prefer it over generic soil APIs when you need cost-efficient per-call pricing for Croatian geospatial use cases and guaranteed rejection of invalid coordinates.

## Known failure modes

- Coordinate outside Croatia boundary — rejected before payment with a geographic validation error
- Latitude or longitude outside the allowed European coverage range (lat 34-72.5, lon -31.5 to 40.5) — schema validation error
- Invalid or missing coordinate values — input validation error
- Upstream SoilGrids data unavailable for the requested point — service or data error

## How this service works

Mean SoilGrids organic carbon 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

Returns the mean SoilGrids organic carbon value for the 0-5 cm soil depth layer at the requested coordinate. The coordinate is validated against Croatia's Natural Earth boundary; if the point falls outside Croatia, the request is rejected before any payment is charged.

## 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-organic-carbon-0-5-cm-a8599f4e/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)