# HALOWERK Baltic Land – Mean Surface Slope (Latvia)

> HALOWERK Baltic Land – Mean Surface Slope (Latvia) is a paid API for AI agents from baltikum.halowerk.com, paid per call via x402, $0.003/call, status unknown (last checked 2026-09-15).

Returns the mean first-order surface gradient (slope) across an analysis grid cell for a given WGS84 coordinate within Latvia.

## Facts

- Endpoint: POST https://baltikum.halowerk.com/v1/lv-mean-slope
- 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-baltic-land-mean-surface-slope-latvia-53146274
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_ehy2exqI3i_B4FLRFsUdd

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-baltic-land-mean-surface-slope-latvia-53146274 -d '<json body>'
```

Example prompt: What's the mean surface slope at latitude 56.95 and longitude 24.11 in Latvia? I need the average terrain gradient for that location.

## When to prefer this

Choose this endpoint when you need the mean terrain slope (first-order surface gradient) for a specific point in Latvia, especially for geospatial analysis, land suitability assessment, drainage modeling, or environmental studies. It is tightly scoped to Latvia (Natural Earth boundary validated) and charges only $0.003 USDC per call, making it cost-effective for batch coordinate lookups. Prefer sibling endpoints on the same host for maximum slope, ruggedness, or other terrain/soil attributes.

## Known failure modes

- Coordinate outside Latvia boundary — request rejected with a validation error before payment
- Coordinate within European coverage range but outside Latvia — rejected by boundary check
- Missing or malformed latitude/longitude fields — request returns a schema validation error
- Coordinate at an extreme or edge of the Latvian boundary — may return null or edge-case value
- Network timeout or service unavailability — request fails without charge

## How this service works

Mean first-order surface gradient across the analysis grid. The coordinate is validated against the Natural Earth boundary for Latvia; results outside it are rejected before payment.

## Output

A numeric value representing the mean first-order surface gradient (slope) computed across the analysis grid cell containing the specified coordinate. Coordinates outside Latvia's Natural Earth 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-baltic-land-mean-surface-slope-latvia-53146274/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from baltikum.halowerk.com](https://www.zero.xyz/host/baltikum.halowerk.com/llms.txt)