# HALOWERK Land Compare – Cropland Change 2020–2021

> HALOWERK Land Compare – Cropland Change 2020–2021 is a paid API for AI agents from landvergleich.halowerk.com, paid per call via x402, $0.008/call, status unknown (last checked 2026-09-15).

Returns the change in cropland share for a 250-metre area in Europe by comparing ESA WorldCover 2020 v100 and 2021 v200 map classifications.

## Facts

- Endpoint: POST https://landvergleich.halowerk.com/v1/worldcover-2020-2021-cropland-change
- Price: $0.008/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-cropland-change-2020-2021-c6a8d5c9
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_07GrO-FMgt1jIG8uapbeP

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-cropland-change-2020-2021-c6a8d5c9 -d '<json body>'
```

Example prompt: What was the change in cropland share between 2020 and 2021 for the 250-metre area around 48.8566° N, 2.3522° E in Europe?

## When to prefer this

Use this endpoint when you need a fast, low-cost satellite-derived signal of cropland change at a specific European location between the 2020 and 2021 ESA WorldCover releases. It is ideal for agricultural monitoring, land-use auditing, or environmental assessment workflows scoped to Europe. Prefer it over manual GIS workflows or full raster downloads when only point-level change is needed.

## Known failure modes

- Coordinates outside European coverage bounds (lat 34–72.5, lon -31.5–40.5) result in an error or empty response
- Invalid or non-numeric latitude/longitude values cause a validation error
- Location falls in an area with no ESA WorldCover data coverage
- Network or payment authorisation failure under x402 protocol

## How this service works

Cropland-share change measured from ESA WorldCover 2020 v100 and 2021 v200 for the same 250 metre analysis area. The result is observed map-class change, not a causal claim.

## Output

A signed numeric value (or structured object) representing the change in cropland share between ESA WorldCover 2020 v100 and 2021 v200 for the 250-metre analysis area centred on the provided coordinate. The result reflects observed map-class change only, not a causal or verified ground-truth finding.

## 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-land-compare-cropland-change-2020-2021-c6a8d5c9/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)