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

> HALOWERK Eastern Land – Bulgaria 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 2026-09-13).

Returns the mean SoilGrids clay fraction for the 0-5 cm topsoil layer at a given coordinate within Bulgaria's boundary.

## Facts

- Endpoint: POST https://ostland.halowerk.com/v1/bg-soil-clay
- Price: $0.004/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/halowerk-eastern-land-bulgaria-soil-clay-fraction-0-5-cm-50669a27
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_3gjJSKbkB4RcN2n9raEaU

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-clay-fraction-0-5-cm-50669a27 -d '<json body>'
```

Example prompt: What's the mean clay fraction in the top 0-5 cm of soil at latitude 42.6977, longitude 23.3219 in Bulgaria?

## When to prefer this

Choose this endpoint when you need point-level SoilGrids clay fraction data specifically within Bulgaria's national boundary at the 0-5 cm depth. It is preferable to a generic SoilGrids API wrapper when you need built-in boundary validation for Bulgaria, pay-per-call pricing via x402, and the convenience of a single-purpose endpoint without managing authentication or large dataset downloads.

## Known failure modes

- Coordinate outside Bulgaria's Natural Earth boundary — request rejected, no charge applied
- Latitude or longitude outside the declared European coverage range (lat 34–72.5, lon -31.5–40.5) — validation error
- Missing or malformed latitude/longitude parameters — schema validation error
- Payment failure or insufficient USDC balance — 402 response
- No SoilGrids data available for the requested coordinate — null or error response

## How this service works

Mean SoilGrids clay fraction 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 value representing the mean clay fraction (as a percentage or volume fraction) in the 0-5 cm topsoil layer at the specified Bulgarian coordinate, derived from SoilGrids data. Coordinates outside Bulgaria's Natural Earth boundary 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-clay-fraction-0-5-cm-50669a27/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)