# HALOWERK Atlantic Land – France Drainage Tendency

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

Returns a relative runoff tendency score derived from terrain slope and surface ruggedness for a given coordinate within France.

## Facts

- Endpoint: POST https://atlantikland.halowerk.com/v1/fr-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-atlantic-land-france-drainage-tendency-b2f9f687
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_2occ3YulAr7ha1dF-daT8

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-atlantic-land-france-drainage-tendency-b2f9f687 -d '<json body>'
```

Example prompt: What's the relative runoff tendency for the terrain at latitude 45.76, longitude 4.83 in France — I need to understand how prone that slope is to surface drainage.

## When to prefer this

Choose this endpoint when you need a terrain-derived runoff or drainage tendency metric specifically for locations within France, particularly when slope and ruggedness are the relevant hydrological signals. It is well-suited for land assessment, agricultural planning, environmental screening, or flood risk workflows where a lightweight per-coordinate score is needed rather than a full hydrological model. The pre-payment boundary validation makes it cost-efficient by rejecting out-of-bounds coordinates before charging.

## Known failure modes

- Coordinate outside France boundary → request rejected before payment, error response indicating invalid location
- Latitude or longitude outside published European coverage range → validation error
- Malformed input JSON or missing required fields → 400-level error
- Service unavailability or upstream terrain data issues → 5xx error

## How this service works

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

## Output

A numeric relative runoff tendency value derived from terrain slope and ruggedness, indicating how strongly a location within France favors surface water drainage; coordinates outside the Natural Earth France boundary 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-atlantic-land-france-drainage-tendency-b2f9f687/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from atlantikland.halowerk.com](https://www.zero.xyz/host/atlantikland.halowerk.com/llms.txt)