# HALOWERK Eastern Land Bulgaria Soil Nitrogen

> HALOWERK Eastern Land Bulgaria Soil Nitrogen 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 total nitrogen content for the 0-5 cm soil layer at a given coordinate within Bulgaria.

## Facts

- Endpoint: POST https://ostland.halowerk.com/v1/bg-soil-nitrogen
- 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-nitrogen-05fccf9b
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_CmWCz8CPBKZRl2z0qPEiK

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-nitrogen-05fccf9b -d '<json body>'
```

Example prompt: What's the mean total nitrogen in the top 0-5 cm of soil at latitude 42.6977 and longitude 23.3219 in Bulgaria? I need the SoilGrids value for that surface layer.

## When to prefer this

Choose this endpoint when you need surface-layer (0-5 cm) total nitrogen data specifically for a coordinate within Bulgaria, backed by SoilGrids. It is ideal for agricultural assessment, environmental monitoring, or land suitability analysis within Bulgaria. The built-in boundary validation ensures you only pay for valid Bulgarian coordinates. Prefer alternatives if you need nitrogen data for other countries, deeper soil horizons, or other soil properties.

## Known failure modes

- Coordinate outside Bulgaria boundary — request rejected with boundary validation error before payment
- Latitude or longitude out of the stated European coverage range (lat 34–72.5, lon -31.5–40.5) — schema validation error
- Missing latitude or longitude parameters — request rejected with input validation error
- SoilGrids data unavailable for the given coordinate — no data returned
- Network timeout or service unavailability — HTTP 5xx error

## How this service works

Mean SoilGrids total nitrogen 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

Returns the mean total nitrogen value (from SoilGrids) for the 0-5 cm soil depth layer at the queried coordinate. The coordinate is validated against the Natural Earth boundary for Bulgaria; if the point falls outside Bulgaria, 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-bulgaria-soil-nitrogen-05fccf9b/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)