{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://raw.githubusercontent.com/api-evangelist/valhalla/main/json-schema/isochrone-request.json",
  "title": "IsochroneRequest",
  "description": "Request body for the Valhalla /isochrone endpoint. Returns GeoJSON polygons or lines representing reachable areas within given time or distance limits.",
  "type": "object",
  "required": ["locations", "costing", "contours"],
  "properties": {
    "locations": {
      "type": "array",
      "minItems": 1,
      "maxItems": 3,
      "description": "Origin locations for the isochrone computation.",
      "items": { "$ref": "location.json" }
    },
    "costing": {
      "type": "string",
      "enum": ["auto", "bicycle", "pedestrian", "truck", "bus", "taxi", "motor_scooter", "motorcycle", "multimodal", "bikeshare", "auto_pedestrian"],
      "description": "Travel mode costing model."
    },
    "contours": {
      "type": "array",
      "minItems": 1,
      "maxItems": 5,
      "description": "Contour limits defining the isochrone rings.",
      "items": {
        "type": "object",
        "description": "A single contour. Specify either time or distance, not both.",
        "properties": {
          "time": {
            "type": "number",
            "minimum": 1,
            "maximum": 100,
            "description": "Travel time limit in minutes."
          },
          "distance": {
            "type": "number",
            "minimum": 1,
            "maximum": 100,
            "description": "Distance limit in kilometers."
          },
          "color": {
            "type": "string",
            "description": "Hex color without '#' for rendering (e.g. 'ff0000')."
          }
        }
      }
    },
    "id": {
      "type": "string",
      "description": "Arbitrary request identifier echoed in the response."
    },
    "polygons": {
      "type": "boolean",
      "default": false,
      "description": "Return polygon geometries instead of linestrings."
    },
    "denoise": {
      "type": "number",
      "minimum": 0,
      "maximum": 1,
      "default": 1.0,
      "description": "Factor to remove smaller contours relative to the largest contour's area."
    },
    "generalize": {
      "type": "number",
      "minimum": 0,
      "description": "Douglas-Peucker generalization tolerance in meters."
    },
    "show_locations": {
      "type": "boolean",
      "default": false,
      "description": "Include input and snapped locations as MultiPoint features in the GeoJSON output."
    },
    "reverse": {
      "type": "boolean",
      "default": false,
      "description": "Compute inbound (reverse) isochrone — areas that can reach the location within the time/distance limit."
    },
    "units": {
      "type": "string",
      "enum": ["km", "miles", "mi"],
      "default": "km"
    },
    "date_time": {
      "type": "object",
      "properties": {
        "type": {
          "type": "integer",
          "enum": [0, 1, 2, 3],
          "description": "0=current, 1=depart_at, 2=arrive_by, 3=invariant"
        },
        "value": {
          "type": "string",
          "description": "ISO 8601 datetime string (YYYY-MM-DDTHH:MM)."
        }
      }
    }
  }
}