# HALOWERK Eastern Land – Croatia Grassland Share

> HALOWERK Eastern Land – Croatia Grassland Share is a paid API for AI agents from ostland.halowerk.com, paid per call via x402, $0.003/call, status unknown (last checked 2026-09-15).

Returns the share of ESA WorldCover 2021 pixels classified as grassland for a given coordinate within Croatia.

## Facts

- Endpoint: POST https://ostland.halowerk.com/v1/hr-grassland-share
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/halowerk-eastern-land-croatia-grassland-share-9664bf34
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_8t12s-StNiunUbRiHWlcU

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-eastern-land-croatia-grassland-share-9664bf34 -d '<json body>'
```

Example prompt: What share of the land around 45.4°N, 16.2°E in Croatia is classified as grassland according to ESA WorldCover 2021?

## When to prefer this

Choose this endpoint when you need a satellite-derived, pixel-level grassland land cover fraction specifically for a coordinate within Croatia. It is ideal for land suitability analysis, ecological assessments, agricultural surveys, or carbon baseline studies where ESA WorldCover 2021 classification is the required data source. Prefer it over generic land cover APIs when Croatian boundary validation and per-call micropayment pricing are acceptable.

## Known failure modes

- Coordinate outside Croatia boundary – rejected before payment with a validation error
- Latitude or longitude out of the published European coverage range (lat 34–72.5, lon -31.5–40.5) – schema validation failure
- Malformed request body – missing latitude or longitude fields returns a 400-level error
- Service unavailability – upstream ESA WorldCover data layer temporarily unreachable

## How this service works

Share of ESA WorldCover 2021 pixels classified as grassland. The coordinate is validated against the Natural Earth boundary for Croatia; results outside it are rejected before payment.

## Output

A numeric value representing the share (fraction or percentage) of ESA WorldCover 2021 pixels classified as grassland within the analysis area centered on the provided coordinate. The coordinate must fall within the Croatian boundary as validated against Natural Earth; requests outside this boundary 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-eastern-land-croatia-grassland-share-9664bf34/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from ostland.halowerk.com](https://www.zero.xyz/host/ostland.halowerk.com/llms.txt)