# HALOWERK Southern Land – Greece Surface Soil Nitrogen

> HALOWERK Southern Land – Greece Surface Soil Nitrogen is a paid API for AI agents from suedland.halowerk.com, paid per call via x402, $0.004/call, status unknown (last checked 2026-09-15).

Returns the mean total nitrogen content (SoilGrids) for the 0–5 cm topsoil layer at a given coordinate within Greece, validated against the Natural Earth boundary.

## Facts

- Endpoint: POST https://suedland.halowerk.com/v1/gr-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-southern-land-greece-surface-soil-nitrogen-419e809c
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_RwCnuTaomwmqABQk11MuR

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-southern-land-greece-surface-soil-nitrogen-419e809c -d '<json body>'
```

Example prompt: What is the mean total nitrogen in the top 5 cm of soil at latitude 37.98, longitude 23.73 in Greece?

## When to prefer this

Choose this endpoint when you need SoilGrids-derived mean total nitrogen specifically for a surface (0–5 cm) soil layer at a point location within Greece. It is ideal for precision agriculture, land valuation, environmental assessments, and site suitability analyses in Greece. Prefer it over generic soil APIs when you need a Greece-validated, pay-per-call micro-service with guaranteed boundary enforcement.

## Known failure modes

- Coordinate outside Greece boundary — request rejected before payment, no result returned
- Latitude or longitude outside the published European coverage range (lat 34–72.5, lon -31.5–40.5) — validation error
- Missing latitude or longitude parameter — schema validation error
- Service unavailable or upstream SoilGrids data not accessible — API 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 Greece; results outside it are rejected before payment.

## Output

Returns the mean total nitrogen value from the SoilGrids dataset for the 0–5 cm surface soil layer at the queried coordinate. The response is only provided for points that fall within the Natural Earth boundary of Greece; out-of-boundary requests are 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-southern-land-greece-surface-soil-nitrogen-419e809c/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from suedland.halowerk.com](https://www.zero.xyz/host/suedland.halowerk.com/llms.txt)