Google Maps Route Planning

Plan multi-stop driving/walking routes for field prospecting visits. Optimizes stop order to minimize travel time so the founder covers more ground per session.

Authentication

• Google Cloud project with Routes API enabled
• API key: GOOGLE_MAPS_API_KEY
• Billing account linked

Compute Routes (point-to-point)

Endpoint: POST https://routes.googleapis.com/directions/v2:computeRoutes

Headers:

Content-Type: application/json
X-Goog-Api-Key: {GOOGLE_MAPS_API_KEY}
X-Goog-FieldMask: routes.duration,routes.distanceMeters,routes.legs,routes.optimizedIntermediateWaypointIndex

Request body (multi-stop with optimization):

{
  "origin": {
    "location": {
      "latLng": { "latitude": 37.7749, "longitude": -122.4194 }
    }
  },
  "destination": {
    "location": {
      "latLng": { "latitude": 37.7849, "longitude": -122.4094 }
    }
  },
  "intermediates": [
    {
      "location": {
        "latLng": { "latitude": 37.7800, "longitude": -122.4150 }
      }
    },
    {
      "location": {
        "latLng": { "latitude": 37.7820, "longitude": -122.4120 }
      }
    }
  ],
  "travelMode": "DRIVE",
  "optimizeWaypointOrder": true,
  "departureTime": "2024-03-15T09:00:00Z"
}

Key parameters:

• optimizeWaypointOrder: true — reorders intermediate stops for shortest total travel time
• travelMode: DRIVE, WALK, BICYCLE, TRANSIT
• departureTime — set to planned visit time for traffic-aware estimates

Response parsing

The response includes optimizedIntermediateWaypointIndex — an array giving the optimal order to visit stops. Use this to reorder the founder's visit schedule.

Each leg contains:

• duration — travel time between stops
• distanceMeters — distance between stops
• startLocation / endLocation — coordinates

Sum all leg durations plus estimated time per visit (e.g., 30 minutes per coworking space) to get total session time.

Building a visit schedule

1. Query google-maps-place-search for venues in the target area
2. Filter to venues open during planned visit window
3. Feed venue coordinates as intermediates to this API with optimizeWaypointOrder: true
4. Parse the optimized order
5. Generate a schedule: arrival time at each stop = departure from previous + leg duration + visit duration

Alternatives

| Tool | API/Method | Notes | |------|-----------|-------| | Google Maps | Routes API | Best for driving, traffic-aware | | Mapbox | Optimization API | Good multi-stop optimization | | HERE | Routing API | Strong commercial vehicle routing | | OSRM | Open Source | Free, self-hosted, no traffic data | | Routific | Route Optimization API | Purpose-built for multi-stop optimization |

Pricing

• Google Maps Routes: $0 for first $200/month credit; ~$5 per 1000 route computations
• Mapbox: 100K free requests/month
• Routific: $0.05/stop for optimization

Error Handling

• MAX_WAYPOINTS_EXCEEDED: Routes API supports up to 25 intermediates. Split into multiple routes if needed.
• NOT_FOUND: One or more locations could not be geocoded. Verify coordinates.
• ZERO_RESULTS: No route exists between the points (e.g., ocean between them).