HALOWERK Land Compare – Maximum Slope Comparison

Use this endpoint when you need a direct pairwise comparison of maximum terrain slope between exactly two European locations, with a clear signed difference and winner — rather than ranking multiple sites or retrieving raw slope data without comparison. Prefer this over generic elevation APIs when you specifically need slope steepness (not just altitude) and want a structured comparative result for European coordinates.

• Coordinates outside European coverage bounds (lat 34–72.5, lon -31.5–40.5) return a coverage error
• Fewer or more than exactly two locations in the input array returns a validation error
• Malformed coordinate values (non-numeric, out-of-range) return a schema validation error
• Payment failure or insufficient funds returns a 402 Payment Required error
• Unavailable elevation/slope data for a specific coordinate may return a data gap error