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Variable: isochrone

const isochrone: ExtendedTool<IsochroneFunctionArgs, IsochroneLlmResult, IsochroneAdditionalData, MapboxToolContext>

Defined in: packages/tools/osm/src/isochrone.ts:116

Isochrone Tool​

This tool generates isochrone polygons showing reachable areas within a given time or distance limit from a starting point using Mapbox's Isochrone API. It supports different transportation modes and can return either polygons or linestrings.

tip

If you don't know the coordinates of the origin point, you can use the geocoding tool to get it.

Example user prompts:

  • "Show me all areas reachable within 15 minutes of Times Square by car"
  • "What areas can I reach within 2km of the Eiffel Tower on foot?"
  • "Generate isochrones for a 30-minute cycling radius from Central Park"

Example​

import { isochrone, IsochroneTool } from "@openassistant/osm";
import { convertToVercelAiTool, ToolCache } from '@openassistant/utils';
import { generateText } from 'ai';

// you can use ToolCache to save the isochrone dataset for later use
const toolResultCache = ToolCache.getInstance();

const isochroneTool: IsochroneTool = {
  ...isochrone,
  toolContext: {
    getMapboxToken: () => process.env.MAPBOX_TOKEN!,
  },
  onToolCompleted: (toolCallId, additionalData) => {
    toolResultCache.addDataset(toolCallId, additionalData);
  },
};

generateText({
  model: openai('gpt-4o-mini', { apiKey: key }),
  prompt: 'What areas can I reach within 2km of the Eiffel Tower on foot?',
  tools: {
    isochrone: convertToVercelAiTool(isochroneTool),
  },
});

For a more complete example, see the OSM Tools Example using Next.js + Vercel AI SDK.