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Zeitgeist — a spike by Chris Gathercole
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  2. Simon Willison — Creator of Datasette; co-creator of Django/

Generating running routes with GPT-6 Astra and ChatGPT Work

Blog · Watch/Read · (gathered 2026-09-13)

  • Simon successfully used ChatGPT Work with GPT-6 Astra to generate complex, looping 5K and 10K running routes from his address, leveraging OpenStreetMap data via Nominatim and Overpass, and producing embedded visualizations, GPX, and GeoJSON files.
  • The visualization was rendered using D3.js within an embedded HTML file, demonstrating the “visualize skill” and its adherence to a Content Security Policy (CSP) that restricts external resources to specific CDNs.
  • A critical “anti-feature” identified is the lack of transparency regarding the actual code executed by the LLM, further exacerbated by “thread compaction” which caused the loss of the generated Python code. Simon suggests LLM systems should preserve pre-compacted text and make it accessible via agent tool calls.