{
  "$schema": "http://json-schema.org/draft-07/schema#",
  "title": "Sovereign Chunk",
  "description": "A text chunk with immutable linkage to its source PDF location.",
  "type": "object",
  "required": ["chunk_id", "doc_id", "text", "spatial_context"],
  "properties": {
    "chunk_id": {"type": "string", "format": "uuid"},
    "doc_id": {"type": "string", "format": "uuid"},
    "text": {"type": "string"},
    "embedding_vector": {
      "type": "array",
      "items": {"type": "number"},
      "minItems": 1536
    },
    "spatial_context": {
      "type": "object",
      "properties": {
        "page_number": {"type": "integer"},
        "bounding_box": {
          "type": "array",
          "items": {"type": "number"},
          "description": "[x_min, y_min, x_max, y_max]"
        }
      }
    }
  }
}