{
  "context": "Evaluates how well the solution leverages the h3 vertex APIs to enumerate vertex identifiers from cells, convert them to coordinates, and deduplicate shared vertices when combining adjacent cells. Focuses on correct use of the package helpers rather than custom geometric calculations or generic control-flow checks.",
  "type": "weighted_checklist",
  "checklist": [
    {
      "name": "Vertex listing",
      "description": "Uses h3.cell_to_vertexes (string API) to return boundary-ordered vertex identifiers with the correct count for hexagon or pentagon cells, matching the stable order expected for the resolution-9 cases.",
      "max_score": 35
    },
    {
      "name": "Input validation",
      "description": "Rejects malformed inputs by checking cells with h3.is_valid_cell and, where applicable, vertex ids with h3.is_valid_vertex before processing, raising ValueError for bad inputs as specified.",
      "max_score": 20
    },
    {
      "name": "LatLng conversion",
      "description": "Converts each vertex identifier to coordinates via h3.vertex_to_latlng, preserves input order, and applies the required six-decimal rounding instead of reconstructing positions from cell boundaries.",
      "max_score": 30
    },
    {
      "name": "Shared vertex map",
      "description": "Builds the multi-cell mapping by deduplicating using the package-provided vertex identifiers (e.g., shared edge yields two shared ids) rather than custom geometric heuristics, keeping each id mapped once to its coordinates.",
      "max_score": 15
    }
  ]
}