Cryptocurrency Market Data MCP Server

Instructions

Implementation Reference

• src/server.py:105-119 (registration)

  Registration of the 'get-price' tool in the handle_list_tools function, defining its name, description, and input schema.

  types.Tool(
      name="get-price",
      description="Get current price of a cryptocurrency pair from a specific exchange",
      inputSchema={
          "type": "object",
          "properties": {
              "symbol": {
                  "type": "string",
                  "description": "Trading pair symbol (e.g., BTC/USDT, ETH/USDT)",
              },
              "exchange": get_exchange_schema()
          },
          "required": ["symbol"],
      },
  ),

• src/server.py:242-251 (handler)

  The core handler logic for the 'get-price' tool within the handle_call_tool function. It retrieves the ticker data using ccxt and returns the current last price.

  if name == "get-price":
      symbol = arguments.get("symbol", "").upper()
      ticker = await exchange.fetch_ticker(symbol)
  
      return [
          types.TextContent(
              type="text",
              text=f"Current price of {symbol} on {exchange_id.upper()}: {ticker['last']} {symbol.split('/')[1]}"
          )
      ]

• src/server.py:108-118 (schema)

  Input schema definition for the 'get-price' tool, specifying required 'symbol' parameter and optional 'exchange'.

  inputSchema={
      "type": "object",
      "properties": {
          "symbol": {
              "type": "string",
              "description": "Trading pair symbol (e.g., BTC/USDT, ETH/USDT)",
          },
          "exchange": get_exchange_schema()
      },
      "required": ["symbol"],
  },

• src/server.py:59-66 (helper)

  Helper function that generates the JSON schema for selecting supported exchanges, referenced in the 'get-price' tool's input schema.

  def get_exchange_schema() -> Dict[str, Any]:
      """Get the JSON schema for exchange selection."""
      return {
          "type": "string",
          "description": f"Exchange to use (supported: {', '.join(SUPPORTED_EXCHANGES.keys())})",
          "enum": list(SUPPORTED_EXCHANGES.keys()),
          "default": "binance"
      }

• src/server.py:31-41 (helper)

  Helper function to retrieve or initialize a CCXT exchange instance, used by the 'get-price' handler.

  async def get_exchange(exchange_id: str) -> ccxt.Exchange:
      """Get or create an exchange instance."""
      exchange_id = exchange_id.lower()
      if exchange_id not in SUPPORTED_EXCHANGES:
          raise ValueError(f"Unsupported exchange: {exchange_id}")
  
      if exchange_id not in exchange_instances:
          exchange_class = SUPPORTED_EXCHANGES[exchange_id]
          exchange_instances[exchange_id] = exchange_class()
  
      return exchange_instances[exchange_id]