# HALOWERK Land Compare – Topsoil pH Two-Point Comparison

> HALOWERK Land Compare – Topsoil pH Two-Point Comparison is a paid API for AI agents from landvergleich.halowerk.com, paid per call via x402, $0.006/call, status unknown (last checked 2026-09-15).

Measures and compares topsoil pH at exactly two European coordinates, returning the signed difference and identifying which location has higher or lower pH.

## Facts

- Endpoint: POST https://landvergleich.halowerk.com/v1/compare-two-soil-ph
- Price: $0.006/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/halowerk-land-compare-topsoil-ph-two-point-comparison-e2a1099a
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_2y_DYyVkPtStsDfKWFqNR

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-land-compare-topsoil-ph-two-point-comparison-e2a1099a -d '<json body>'
```

Example prompt: Compare the topsoil pH between my two farm plots — one at latitude 51.5, longitude 4.3 and the other at latitude 48.8, longitude 2.35 — and tell me which has more acidic soil and by how much.

## When to prefer this

Use this endpoint when you need a direct head-to-head topsoil pH comparison between exactly two European geographic points. It is ideal for agricultural site selection, land due diligence, or soil condition benchmarking where a single consistent measurement method and signed difference are required. Prefer this over general soil APIs when the European coverage area is sufficient and you want a structured comparison result rather than raw per-point data.

## Known failure modes

- Coordinates outside European coverage bounds (latitude 34–72.5, longitude -31.5–40.5) return a validation error
- Fewer or more than exactly two location objects in the array are rejected
- Invalid or missing latitude/longitude values cause a schema validation error
- Payment failure via x402 protocol prevents the call from completing

## How this service works

Measures topsoil ph for exactly two European coordinates with one method and reports the signed difference and winner where meaningful.

## Output

Returns the topsoil pH value measured at each of the two provided European coordinates, the signed numerical difference between them (location A minus location B), and an indication of which location has the higher or lower pH where the difference is meaningful.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "locations": {
   "type": "array",
   "items": {
    "type": "object",
    "required": [
     "longitude",
     "latitude"
    ],
    "properties": {
     "name": {
      "type": "string",
      "maxLength": 60,
      "minLength": 1
     },
     "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."
     }
    },
    "additionalProperties": false
   },
   "maxItems": 2,
   "minItems": 2
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/halowerk-land-compare-topsoil-ph-two-point-comparison-e2a1099a/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from landvergleich.halowerk.com](https://www.zero.xyz/host/landvergleich.halowerk.com/llms.txt)