/axiom-location

name: axiom-location
description: Use when implementing location services, maps, geofencing, or debugging location/MapKit issues. Covers Core Location, CLMonitor, MapKit, annotations, directions.
license: MIT

Location & Maps

**You MUST use this skill for ANY location services, mapping, geofencing, or Core Location / MapKit work.**

Quick Reference

| Symptom / Task | Reference | |----------------|-----------| | Authorization strategy (When In Use vs Always) | See `skills/core-location.md` | | Monitoring approach (continuous, significant-change, CLMonitor) | See `skills/core-location.md` | | Accuracy selection, background location | See `skills/core-location.md` | | CLLocationUpdate, CLMonitor, CLServiceSession APIs | See `skills/core-location-ref.md` | | Authorization API patterns, geofencing API | See `skills/core-location-ref.md` | | Compass heading, heading reference body (`headingBody`) | See `skills/core-location-ref.md` (Part 12) | | Location updates never arrive | See `skills/core-location-diag.md` | | Background location stops working | See `skills/core-location-diag.md` | | Authorization always denied, geofence failures | See `skills/core-location-diag.md` | | SwiftUI Map, annotations, markers, clustering | See `skills/mapkit.md` | | MKMapView vs SwiftUI Map decision | See `skills/mapkit.md` | | Search, directions, routing | See `skills/mapkit.md` | | MapKit API: Marker, Annotation, MKLocalSearch, MKDirections | See `skills/mapkit-ref.md` | | Look Around, MKMapSnapshotter, MKMapItem | See `skills/mapkit-ref.md` | | Annotations not appearing, region jumping | See `skills/mapkit-diag.md` | | Clustering not working, search failures | See `skills/mapkit-diag.md` | | Overlay rendering, user location not showing | See `skills/mapkit-diag.md` |

Decision Tree

digraph location {
    start [label="Location / Maps task" shape=ellipse];
    domain [label="Core Location or MapKit?" shape=diamond];
    cl_type [label="Need what?" shape=diamond];
    mk_type [label="Need what?" shape=diamond];

    start -> domain;

    domain -> cl_type [label="Core Location"];
    domain -> mk_type [label="MapKit / Maps"];

    cl_type -> "skills/core-location.md" [label="authorization, monitoring\nstrategy, accuracy,\nbackground location"];
    cl_type -> "skills/core-location-ref.md" [label="API syntax\n(CLLocationUpdate,\nCLMonitor, CLServiceSession)"];
    cl_type -> "skills/core-location-diag.md" [label="something broken\n(no updates, denied,\ngeofence not firing)"];

    mk_type -> "skills/mapkit.md" [label="patterns, decisions\n(SwiftUI Map vs MKMapView,\nannotations, search)"];
    mk_type -> "skills/mapkit-ref.md" [label="API syntax\n(Marker, Annotation,\nMKLocalSearch, MKDirections)"];
    mk_type -> "skills/mapkit-diag.md" [label="something broken\n(annotations missing,\nregion jumping, clustering)"];
}

1. Authorization strategy, monitoring approach, accuracy? → `skills/core-location.md` 1a. Need specific API syntax (CLLocationUpdate, CLMonitor, CLServiceSession)? → `skills/core-location-ref.md` 1b. Location not working? → `skills/core-location-diag.md` 2. Adding a map, annotations, search, directions? → `skills/mapkit.md` 2a. Need specific MapKit API syntax (Marker, MKLocalSearch, MKDirections)? → `skills/mapkit-ref.md` 2b. Map display broken? → `skills/mapkit-diag.md` 3. Location draining battery? → See axiom-performance (skills/energy.md) 4. Background task scheduling for location? → See axiom-integration 5. Privacy manifest for location? → See axiom-integration

Conflict Resolution

**location vs axiom-performance**: When location is draining battery: 1. **Try location FIRST** — Excessive accuracy or continuous updates are the #1 cause. `skills/core-location.md` covers accuracy selection and monitoring strategy. 2. **Only use axiom-performance** if location settings are already correct — Profile after ruling out obvious over-tracking.

**location vs axiom-integration**: When implementing background location:

• Background location configuration (Info.plist, capabilities, CLServiceSession) → **use location**
• BGTaskScheduler for periodic location processing → **use axiom-integration**

**location vs axiom-data**: When storing or syncing location data:

• Getting location updates, geofencing → **use location**
• Persisting location history, CloudKit sync → **use axiom-data**

**location vs axiom-build**: When location permissions fail in simulator:

• Authorization dialogs, Info.plist keys → **use location** (`skills/core-location-diag.md`)
• Simulator GPS simulation, `simctl location` → **use axiom-build**

Critical Patterns

**Core Location** (`skills/core-location.md`):

• Authorization escalation strategy (When In Use first, Always later)
• Monitoring decision tree (continuous vs significant-change vs CLMonitor)
• Accuracy selection with battery impact
• Background location configuration
• Anti-patterns with time costs (premature Always authorization, unnecessary continuous updates)

**Core Location API** (`skills/core-location-ref.md`):

• CLLocationUpdate AsyncSequence (iOS 17+)
• CLMonitor condition-based geofencing (iOS 17+)
• CLServiceSession declarative authorization (iOS 18+)
• Authorization API patterns, background mode configuration

**Core Location Diagnostics** (`skills/core-location-diag.md`):

• Location updates never arrive
• Background location stops working
• Authorization always denied
• Geofence events not triggering
• Location accuracy unexpectedly poor

**MapKit** (`skills/mapkit.md`):

• SwiftUI Map vs MKMapView decision tree
• Annotation patterns (Marker, custom Annotation)
• Search (MKLocalSearch, autocomplete)
• Directions and routing
• Anti-patterns (annotations in view body, no view reuse, setRegion loops)

**MapKit API** (`skills/mapkit-ref.md`):

• SwiftUI Map API (MapCameraPosition, content builders, controls)
• MKMapView delegate patterns
• MKLocalSearch, MKDirections
• Look Around, MKMapSnapshotter
• Clustering configuration

**Ma