# HALOWERK Southern Land – Greece Drainage Tendency

> HALOWERK Southern Land – Greece Drainage Tendency is a paid API for AI agents from suedland.halowerk.com, paid per call via x402, $0.003/call, status unknown (last checked 2026-09-15).

Returns a relative runoff/drainage tendency score for a coordinate in Greece, derived from terrain slope and ruggedness metrics.

## Facts

- Endpoint: POST https://suedland.halowerk.com/v1/gr-drainage-tendency
- 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-southern-land-greece-drainage-tendency-003cf02d
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_W1XsqlaaHUD-hW_CVAU_J

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-southern-land-greece-drainage-tendency-003cf02d -d '<json body>'
```

Example prompt: What's the drainage tendency score for the location at 37.9838° N, 23.7275° E in Greece — I want to understand how prone this site is to surface runoff based on slope and terrain ruggedness.

## When to prefer this

Use this endpoint when you need a terrain-derived drainage or runoff tendency index specifically for a location in Greece and want automatic boundary validation before payment. Prefer it over generic elevation APIs when the downstream use case requires hydrological context (runoff risk, land drainage suitability) rather than raw elevation data.

## Known failure modes

- Coordinate outside Greece boundary — request rejected before payment, returns validation error
- Latitude or longitude out of allowed range (lat 34–72.5, lon -31.5–40.5) — schema validation error
- Invalid or missing coordinate fields — returns 400-level error
- Service unavailable or timeout — returns 5xx error

## How this service works

Relative runoff tendency derived from slope and ruggedness. The coordinate is validated against the Natural Earth boundary for Greece; results outside it are rejected before payment.

## Output

A numeric score representing the relative runoff/drainage tendency at the queried coordinate, derived from slope steepness and terrain ruggedness. Coordinates outside the validated Natural Earth boundary for Greece 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-southern-land-greece-drainage-tendency-003cf02d/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from suedland.halowerk.com](https://www.zero.xyz/host/suedland.halowerk.com/llms.txt)