Banxico MCP Server

Instructions

Implementation Reference

• banxico_mcp_server.py:541-568 (handler)

  Handler function for get_banxico_reserves_data tool. Fetches reserve assets data (series SF308843) from Banxico API, applies optional limit to recent data points, and formats the output using format_financial_data.

  @mcp.tool()
  async def get_banxico_reserves_data(limit: Optional[int] = 30) -> str:
      """
      Get Banxico Reserve Assets data.
      
      Args:
          limit: Maximum number of recent data points (default: 30)
          
      Returns:
          Current and historical Banxico reserve assets data
      """
      if not BANXICO_TOKEN:
          return "Error: BANXICO_API_TOKEN environment variable not set. Please configure your API token."
      
      endpoint = "series/SF308843/datos"
      data = await make_banxico_request(endpoint, BANXICO_TOKEN)
      
      if not data:
          return "Failed to retrieve Banxico reserve assets data. Please check your API token and network connection."
      
      # Apply limit if specified
      if limit and data.get("bmx", {}).get("series"):
          for series in data["bmx"]["series"]:
              if "datos" in series and len(series["datos"]) > limit:
                  series["datos"] = series["datos"][-limit:]
      
      return format_financial_data(data)

• banxico_mcp_server.py:43-69 (helper)

  Helper function to make authenticated HTTP requests to the Banxico SIE API, used by get_banxico_reserves_data.

  async def make_banxico_request(endpoint: str, token: str) -> dict[str, Any] | None:
      """
      Make a request to the Banxico SIE API with proper error handling.
      
      Args:
          endpoint: The API endpoint to call (without base URL)
          token: The Banxico API token
          
      Returns:
          JSON response data or None if request failed
      """
      url = f"{BANXICO_API_BASE}/{endpoint}"
      headers = {"User-Agent": USER_AGENT}
      params = {"token": token}
      
      try:
          async with httpx.AsyncClient() as client:
              response = await client.get(url, headers=headers, params=params, timeout=30.0)
              response.raise_for_status()
              return response.json()
      except httpx.HTTPError as e:
          logger.error(f"HTTP error occurred: {e}")
          return None
      except Exception as e:
          logger.error(f"An error occurred: {e}")
          return None

• banxico_mcp_server.py:219-269 (helper)

  Helper function to format financial data (used for reserves), including units, recent data points with comma-formatted large numbers.

  def format_financial_data(data: dict[str, Any]) -> str:
      """
      Format financial data with appropriate units and formatting.
      
      Args:
          data: Raw JSON response from Banxico API
          
      Returns:
          Formatted string with financial data
      """
      if not data or "bmx" not in data:
          return "No financial data available"
      
      series_list = data["bmx"].get("series", [])
      if not series_list:
          return "No financial series found"
      
      result = []
      for series in series_list:
          title = series.get("titulo", "Unknown Series")
          series_id = series.get("idSerie", "Unknown ID")
          unit = series.get("unidad", "")
          result.append(f"💰 {title} (ID: {series_id})")
          if unit:
              result.append(f"  Unit: {unit}")
          
          datos = series.get("datos", [])
          if not datos:
              result.append("  No data points available")
          else:
              result.append(f"  Total data points: {len(datos)}")
              # Show recent data points with number formatting
              display_count = min(len(datos), 10)
              for dato in datos[-display_count:]:
                  fecha = dato.get("fecha", "Unknown date")
                  valor = dato.get("dato", "N/A")
                  # Format large numbers with commas
                  if valor != "N/A" and valor is not None:
                      try:
                          valor_num = float(valor)
                          if valor_num >= 1000:
                              valor = f"{valor_num:,.2f}"
                          else:
                              valor = f"{valor_num}"
                      except (ValueError, TypeError):
                          pass
                  result.append(f"  {fecha}: {valor}")
          
          result.append("")  # Empty line between series
      
      return "\n".join(result)

• banxico_mcp_server.py:541-541 (registration)

  FastMCP decorator that registers the get_banxico_reserves_data function as a tool.

  @mcp.tool()