Mapbox Location Grounding

Mapbox Location Grounding Skill

Teaches AI assistants how to ground location-aware responses in live Mapbox data by composing MCP tools into a structured, cited answer. Use this instead of relying on training data for place names, POIs, ratings, or travel times — which are stale and prone to hallucination.

When to Use Grounding

Ground responses when the user asks about:

• "What's near [location]?" or "What's around [coordinate]?"
• "Describe this neighborhood / area"
• "Find [category] within walking/driving distance"
• "What can I do near [address]?"
• "How long does it take to get from A to B?"
• "What's within a 10-minute walk of here?"
• "How far is it between these locations?"
• Real estate, travel, mobility, or local discovery use cases
• Any question where place accuracy, recency, or travel time matters

Never answer location questions from training data alone. Always retrieve live data.

Grounding Tool Composition

Preferred: single tool call

If ground_location_tool is available, use it — it handles reverse geocoding, POI search, place details enrichment, isochrone, and a static map image in one call:

ground_location_tool(
  longitude, latitude,
  query: "restaurant",   // optional — category or subcategory of nearby places to find
  profile: "mapbox/walking",    // optional — travel profile for isochrone
  contours_minutes: [5, 10, 15]
)

Returns:

• Neighborhood/place name from reverse geocoding
• Nearby POIs with distances, ratings, price levels, and popularity (when available)
• Travel-time reachability from isochrone
• A static map image for visual context
• Citations for all data sources

Do not call reverse_geocode_tool, category_search_tool, place_details_tool, or isochrone_tool separately — they are already composed inside this tool.

Query parameter

The query parameter accepts category or subcategory terms — not attribute preferences:

• Supported: "restaurant", "coffee", "park", "Italian restaurant", "EV charging station"
• Not supported: "family-friendly", "fast charging", "outdoor seating" — these are not filterable attributes in Mapbox data

To help users find places matching a preference (e.g. "family-friendly"), search by category ("restaurant") and use the returned rating and price data to inform the recommendation.

Fallback: manual composition

If ground_location_tool is not available, build the grounded response by composing these tools in order:

Step 1 — Establish place context

reverse_geocode_tool(longitude, latitude, types: "neighborhood,locality,place")

Returns: neighborhood, city, region, country. This is the anchor for the response.

Step 2 — Retrieve nearby POIs

For specific names or brands:

search_and_geocode_tool(query, proximity: {longitude, latitude}, limit: 10)

For generic categories:

category_search_tool(category, proximity: {longitude, latitude}, limit: 10)

Step 3 — Enrich POIs with ratings and price (optional but high-value)

For each POI with a mapbox_id, call in parallel:

place_details_tool(mapbox_id, attribute_sets: ["visit"])

Returns: rating, price level, popularity, and opening hours per place.

Step 4 — Add travel-time context (optional but high-value)

isochrone_tool(
  coordinates: {longitude, latitude},
  profile: "mapbox/walking",    // or "mapbox/driving", "mapbox/cycling", "mapbox/driving-traffic"
  contours_minutes: [5, 10, 15]
)

Returns a polygon showing what's reachable within each time threshold.

Step 5 — Visual grounding (optional)

static_map_image_tool(longitude, latitude, zoom: 14)

Returns a map image that can be included in the response for visual context.

Grounded Response Structure

Always structure grounded responses with explicit citations:

Place: [neighborhood, city from reverse_geocode]
Nearby [category]: [list from search/category tool, with names, ratings, prices, and distances]
Travel context: [X min walk / Y min drive from isochrone]
Sources: Mapbox Search, Mapbox Directions (live data)

Example grounded response:

> SoMa, San Francisco, CA (live Mapbox data)

>

> Restaurants within walking distance:

>

> - Bix Restaurant $$ ★8.4 — 56 Gold St (180m)

> - The Bird $ ★7.9 — 115 New Montgomery St (320m)

> - Oren's Hummus $$ ★8.1 — 131 Townsend St (510m)

>

> Reachable by walking: 5 min, 10 min, 15 min

>

> _Sources: Mapbox Geocoding API, Mapbox Search API, Mapbox Place Details API, Mapbox Isochrone API, Mapbox Static Images API_

Routing Grounding

For questions about travel between two locations, use directions_tool. For questions about reachable area, use isochrone_tool. For comparing travel times across multiple locations, use matrix_tool.

Point-to-point travel time and distance

> "How long does it take to drive from Pike Place Market to Capitol Hill?"

> "What's the fastest route from the hotel to the airport?"

directions_tool(
  waypoints: [{longitude, latitude}, {longitude, latitude}],
  profile: "mapbox/driving-traffic"   // live traffic; or "mapbox/walking", "mapbox/cycling", "mapbox/driving"
)

Returns: duration (with live traffic), distance, turn-by-turn steps, and an encoded polyline for map rendering. Supports up to 25 waypoints for multi-stop routes.

Area reachability ("within X minutes")

> "What's reachable within a 10-minute walk?"

> "Show me what I can reach in 15 minutes by car from here"

isochrone_tool(
  coordinates: {longitude, latitude},
  profile: "mapbox/walking",
  contours_minutes: [5, 10, 15]
)

Returns a polygon showing the area reachable within each time threshold. Combine with category_search_tool or ground_location_tool to answer "what restaurants are within a 10-minute walk?" — use the isochrone to define the boundary, then search within it.

Multi-location travel time matrix

> "Which of these three offices is closest to my location?"

> "What are travel times from this warehouse to each of our delivery zones?"

> "Compare commute times to multiple locations"

Use matrix_tool — do NOT call directions_tool separately for each pair. Matrix batches all pairs in a single API call.

matrix_tool(
  sources: [{longitude, latitude}, ...],
  destinations: [{longitude, latitude}, ...],
  profile: "mapbox/driving-traffic"
)

Returns a matrix of durations and distances between every source/destination pair. Rank results by duration to find the nearest location. One matrix_tool call replaces N separate directions_tool calls.

Proximity search with routing context

For "find [category] within X minutes of [location]":

• Geocode the origin if needed: search_and_geocode_tool(address)
• Get the reachable area: isochrone_tool(coordinates, profile, contours_minutes)
• Search for POIs: ground_location_tool(longitude, latitude, query: "category") — the isochrone

contours tell the user what's within each time band

Or more directly: ground_location_tool returns both nearby POIs and isochrone reachability in one

call, which covers most proximity + routing use cases without additional composition.

Example routing response

> Pike Place Market → Capitol Hill, Seattle

>

> By car (with traffic): 12 min, 3.2 km via Pine St

> By walking: 28 min, 2.1 km

> By cycling: 14 min, 2.3 km

>

> _Source: Mapbox Directions API (live traffic)_

What Mapbox Grounding Offers vs. Training Data

| | Training Data | Mapbox Grounding |

| ------------------ | ------------------- | --------------------------- |

| POI accuracy | Stale, hallucinated | Live, verified |

| Ratings/price | Often wrong | Live via Place Details |

| Business hours | Often wrong | Live via Place Details |

| Travel times | Estimated | Live traffic via Directions |

| Reachable area | Not available | Isochrone polygons |

| Multi-stop routing | Not available | Up to 25 waypoints |

| New places | Missing | Indexed |

| Map image | None | Inline static map |

| Citations | None | Tool + API source |

Important Limitations

• Attribute filtering (family-friendly, outdoor seating, fast charging) is not supported by the category search API. Use category terms and let rating/price data inform preference-based recommendations.
• POI coverage varies by region. If search returns few results, say so rather than padding with guesses.
• Coordinates required for proximity search — if the user provides an address, geocode it first with search_and_geocode_tool before running category search.

Anti-Patterns to Avoid

• Answering "what's near X?" from training data without calling search tools
• Estimating travel times without calling directions_tool or isochrone_tool
• Hallucinating business names, hours, or ratings
• Calling reverse_geocode_tool + category_search_tool + place_details_tool separately when ground_location_tool is available
• Using attribute terms like "family-friendly" as the query parameter — use the category instead
• Returning raw tool output without synthesizing into a readable response
• Omitting citations — always indicate the response is grounded in live Mapbox data