Add 8 offline geospatial tools using Turf.js

[mattpodwysocki]

Summary

Adds 8 fundamental geospatial calculation tools that work completely offline without requiring Mapbox API calls. These tools provide AI agents with essential spatial reasoning capabilities.

New Tools

All tools use Turf.js for accurate geospatial calculations:

1. distance_tool - Calculate distance between coordinates using Haversine formula

   • Supports: kilometers, miles, meters, feet, nautical miles

2. point_in_polygon_tool - Test if a point is inside a polygon

   • Useful for: "Is this delivery address in our service area?"

3. bearing_tool - Calculate compass direction between coordinates

   • Returns: bearing in degrees (0-360°) plus cardinal direction (N, NE, E, etc.)

4. midpoint_tool - Find geographic midpoint along great circle path

   • Useful for: "What's halfway between San Francisco and New York?"

5. centroid_tool - Calculate center point of polygons/multipolygons

   • Returns: geometric center of any shape

6. area_tool - Calculate polygon area

   • Supports: square meters, kilometers, acres, hectares, miles, feet

7. bbox_tool - Calculate bounding box of any geometry

   • Works with: points, lines, polygons, multipolygons
   • Returns: [minLon, minLat, maxLon, maxLat]

8. buffer_tool - Create buffer zones around geometries

   • Useful for: "Show me all locations within 5km of this point"

9. simplify_tool - Reduce vertex count using Douglas-Peucker algorithm

   • Useful for: reducing file sizes, improving rendering performance

Implementation Details

• All tools extend BaseTool (not MapboxApiBasedTool) for offline operation
• Set openWorldHint: false to indicate no external API calls
• Coordinate inputs use objects {longitude, latitude} instead of tuples to avoid JSON schema issues
• OpenTelemetry tracing integrated for all tools
• Proper error handling and structured output

SDK Update

Also updates @modelcontextprotocol/sdk from 1.25.1 → 1.25.2 to fix CVE. Updated patch file removes icons support (that belongs in #93) and keeps only output validation fixes.

Testing

✅ All 457 tests passing
✅ Build successful
✅ Input schema validation (no z.tuple() usage)
✅ Annotations tests updated for offline tools

Example Usage

// Calculate distance
await distance_tool.run({
  from: { longitude: -122.4194, latitude: 37.7749 }, // SF
  to: { longitude: -118.2437, latitude: 34.0522 },   // LA
  units: "miles"
});
// Returns: ~347 miles

// Check if point is in polygon
await point_in_polygon_tool.run({
  point: { longitude: -122.4, latitude: 37.8 },
  polygon: [[[/* SF Bay Area polygon */]]]
});
// Returns: { inside: true }

// Create 5km buffer zone
await buffer_tool.run({
  geometry: [-122.4194, 37.7749], // Point
  distance: 5,
  units: "kilometers"
});
// Returns: Polygon representing 5km buffer

🤖 Generated with Claude Code

[mattpodwysocki]

Closing to recreate with offline-only tools (splitting API tools into separate PR)