Geocode Supabase queued addresses with Nominatim & Claude

Geocode your queued Supabase addresses daily—using Nominatim first, Claude fallback

This n8n workflow automatically geocodes up to 100 pending place records in your Supabase table every day. It queries OpenStreetMap Nominatim for precise matches, and if that fails, it uses Claude to derive district-level centroid coordinates—then writes latitude/longitude and a precision/source label back to Supabase.

What this workflow does

• Runs daily at 07:00 on a schedule.
• Loads up to 100 rows from a specified Supabase table where status is set to your configured pending value.
• Iterates each place, waits 2.1 seconds between requests to respect Nominatim rate limits, then searches using district + city + country.
• If Nominatim returns coordinates, the workflow updates Supabase with geo_lat, geo_lon, and tags the record as coming from a precise Nominatim lookup.
• If Nominatim has no precise hit, it asks Anthropic Claude for the district centroid and parses a JSON-only response.
• If Claude provides coordinates, it updates Supabase with geo_lat/geo_lon and labels the result as coming from the LLM.
• If Claude declines, it retries Nominatim at the city level and stores fallback coordinates (or leaves the row pending to retry next run).

Use cases

• Geocoding “address/place” data for mapping, proximity searches, and analytics.
• Keeping a Supabase-backed dataset continuously enriched with latitude/longitude without manual work.
• Handling messy or inconsistent place names where street-level geocoding often fails—by falling back to district centroids.

Technical details

• n8n schedule (daily at 07:00)
• Supabase node for reading/updating the geocode queue table
• Nominatim (OpenStreetMap) lookups with district + city + country, then city-level fallback
• Anthropic Claude fallback for district-level centroid coordinates (expects JSON-only output)
• Uses n8n logic nodes such as if, set, code, wait, no op, and supabase