# HALOWERK Eastern Land – Bulgaria Soil CEC (0-5 cm)

> HALOWERK Eastern Land – Bulgaria Soil CEC (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 cation exchange capacity (CEC) for the 0–5 cm soil layer at a given coordinate within Bulgaria.

## Facts

- Endpoint: POST https://ostland.halowerk.com/v1/bg-soil-cec
- 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-bulgaria-soil-cec-0-5-cm-4c98a963
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_suXC5KQYeK3y7yk4qEPYz

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-bulgaria-soil-cec-0-5-cm-4c98a963 -d '<json body>'
```

Example prompt: What is the mean cation exchange capacity of the topsoil at latitude 42.15, longitude 24.75 in Bulgaria?

## When to prefer this

Use this endpoint when you need SoilGrids-derived topsoil cation exchange capacity specifically for a point location in Bulgaria and want a low-cost, per-call microservice with boundary pre-validation. Prefer it over general SoilGrids API access when you need guaranteed Bulgaria-scope filtering and x402 micropayment compatibility.

## Known failure modes

- Coordinate outside Bulgaria boundary — request rejected with a validation error before payment
- Latitude or longitude outside published European coverage range — schema validation failure
- SoilGrids data unavailable for the exact cell — may return null or no-data indicator
- Malformed request body — HTTP 400 bad request

## How this service works

Mean SoilGrids cation exchange capacity for the 0-5 cm layer. The coordinate is validated against the Natural Earth boundary for Bulgaria; results outside it are rejected before payment.

## Output

A numeric mean cation exchange capacity value (cmolc/kg) from SoilGrids for the 0–5 cm depth layer at the requested Bulgarian coordinate. Coordinates outside the Bulgaria boundary (validated against Natural Earth) are rejected before any charge is applied.

## 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-bulgaria-soil-cec-0-5-cm-4c98a963/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)