What is the correct JSON schema format for Claude tool definitions?

JSON Tool Definition Template

{
  "name": "get_stock_price",
  "description": "Retrieves the current trading stock price for a symbol.",
  "input_schema": {
    "type": "object",
    "properties": {
      "ticker": {
        "type": "string",
        "description": "The stock ticker symbol (e.g. AAPL)."
      }
    },
    "required": ["ticker"]
  }
}