# HALOWERK Land Compare – Water & Wetland Change (WorldCover 2020→2021)

> HALOWERK Land Compare – Water & Wetland Change (WorldCover 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 water and wetland land-cover share at a given European location by comparing ESA WorldCover 2020 v100 and 2021 v200 within a 250-metre analysis area.

## Facts

- Endpoint: POST https://landvergleich.halowerk.com/v1/worldcover-2020-2021-water-wetland-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-water-wetland-change-worldcover-2020-2021-c33fa026
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_0GUw7mDOQ9j79ZmVXuMCk

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-water-wetland-change-worldcover-2020-2021-c33fa026 -d '<json body>'
```

Example prompt: Using ESA WorldCover data, what was the change in water and wetland coverage between 2020 and 2021 at latitude 52.3 and longitude 4.9 in the Netherlands?

## When to prefer this

Use this endpoint when you need a precise, consistent, single-method comparison of water and wetland land-cover share change at a specific European point between 2020 and 2021, sourced from ESA WorldCover. Prefer it over general GIS tools when you want a pay-per-call, lightweight lookup without needing to manage raster data yourself. It is ideal for environmental monitoring, due diligence, or land-change analytics scoped to European geographies.

## Known failure modes

- Coordinates outside European coverage bounds (lat 34–72.5, lon -31.5–40.5) will be rejected
- Non-numeric or missing latitude/longitude values result in validation errors
- No change detected if both years show identical land-cover classification in the area
- Service may return error if the ESA WorldCover tile for the location has missing data

## How this service works

Water and wetland-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

Returns the observed change in water and wetland land-cover share (as a signed numeric value) between ESA WorldCover 2020 v100 and 2021 v200 for the 250-metre area around the provided European coordinate. This is a map-class observation, not a causal interpretation.

## 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-water-wetland-change-worldcover-2020-2021-c33fa026/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)