# HALOWERK Eastern Land — Croatia Built-Up Share

> HALOWERK Eastern Land — Croatia Built-Up 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 built-up (urban/impervious surface) for a given coordinate within Croatia.

## Facts

- Endpoint: POST https://ostland.halowerk.com/v1/hr-built-up-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-built-up-share-9aa2a5e5
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Jl8P0DU5SAqTV0XpGm6xi

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-built-up-share-9aa2a5e5 -d '<json body>'
```

Example prompt: What share of ESA WorldCover 2021 pixels around latitude 45.8150, longitude 15.9819 in Zagreb, Croatia are classified as built-up?

## When to prefer this

Choose this endpoint when you need pixel-level built-up land cover statistics for a specific point in Croatia using the authoritative ESA WorldCover 2021 dataset. It is ideal for urban density analysis, site assessments, environmental reporting, or any geospatial pipeline that requires quantified impervious-surface fractions validated against official Croatian boundaries. It is not suitable for coordinates outside Croatia or for other land cover classes such as tree cover (use the sibling tree-cover endpoint instead).

## Known failure modes

- Coordinate outside Croatia boundary — rejected before payment with a validation error
- Latitude or longitude outside European coverage range (lat 34–72.5, lon -31.5–40.5) — schema validation failure
- Malformed request body or missing required parameters — HTTP 400
- Service unavailability or upstream ESA data access failure — HTTP 500
- Payment failure or insufficient USDC balance — HTTP 402

## How this service works

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

## Output

A numeric value representing the fraction (share) of ESA WorldCover 2021 raster pixels classified as built-up within the analysis area surrounding the given coordinate inside Croatia. The response covers only coordinates validated against the Natural Earth boundary for Croatia; out-of-bounds coordinates are rejected before any charge is applied.

## 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-built-up-share-9aa2a5e5/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)