# HALOWERK Southern Land – Spain Soil Nitrogen (0-5 cm)

> HALOWERK Southern Land – Spain Soil Nitrogen (0-5 cm) 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 SoilGrids total nitrogen concentration for the 0–5 cm topsoil layer at a given coordinate within Spain.

## Facts

- Endpoint: POST https://suedland.halowerk.com/v1/es-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-spain-soil-nitrogen-0-5-cm-bd514033
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_uANxjvFk-JymtGRwxYAws

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-spain-soil-nitrogen-0-5-cm-bd514033 -d '<json body>'
```

Example prompt: What's the mean total nitrogen in the top 0–5 cm of soil at latitude 40.4168 and longitude -3.7038 in Spain? I need the SoilGrids figure for that surface layer.

## When to prefer this

Choose this endpoint when you need point-specific SoilGrids total nitrogen data for a location confirmed to be within Spain and want a single authoritative topsoil (0–5 cm) reading. Prefer it over generic soil APIs when Spain-scoped validation, micro-payment per-call pricing, and SoilGrids provenance are required. It is part of a suite of sibling endpoints covering other soil and land-cover metrics for the same region.

## Known failure modes

- Coordinate outside Spain boundary – request rejected before charge; returns an error indicating the point is out of coverage
- Latitude or longitude outside the accepted European range (34–72.5°N, -31.5–40.5°E) – schema validation failure
- Missing required latitude or longitude parameter – request rejected with validation error
- SoilGrids data unavailable for the specific pixel – may return null or data gap error
- Network timeout or upstream SoilGrids service unavailability

## How this service works

Mean SoilGrids total nitrogen for the 0-5 cm layer. The coordinate is validated against the Natural Earth boundary for Spain; results outside it are rejected before payment.

## Output

A single numeric value representing the mean SoilGrids total nitrogen concentration (likely in g/kg or cg/kg) for the 0–5 cm soil layer at the queried coordinate within Spain. Coordinates outside the Spain boundary are rejected before payment is processed.

## 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-spain-soil-nitrogen-0-5-cm-bd514033/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)