CSV MCP Server

Instructions

Add a new row to the CSV file.

Args:
    filename: Name of the CSV file
    row_data: Dictionary mapping column names to values

Returns:
    Dictionary with addition results

Implementation Reference

• csv_mcp_server/server.py:110-125 (handler)

  MCP tool handler for 'add_row': decorated with @mcp.tool(), defines input schema via type hints and docstring, delegates execution to CSVManager.add_row with error handling.

  @mcp.tool()
  def add_row(filename: str, row_data: Dict[str, Any]) -> Dict[str, Any]:
      """
      Add a new row to the CSV file.
      
      Args:
          filename: Name of the CSV file
          row_data: Dictionary mapping column names to values
      
      Returns:
          Dictionary with addition results
      """
      try:
          return csv_manager.add_row(filename, row_data)
      except Exception as e:
          return {"success": False, "error": str(e)}

• csv_mcp_server/csv_manager.py:227-258 (helper)

  Core logic implementation in CSVManager.add_row: loads CSV with pandas, creates new row from dict, appends it, saves with backup and size validation.

  def add_row(self, filename: str, row_data: Dict[str, Any]) -> Dict[str, Any]:
      """Add a new row to the CSV file."""
      filepath = self._get_file_path(filename)
      
      if not filepath.exists():
          raise FileNotFoundError(f"CSV file '{filename}' not found")
      
      # Create backup
      self._create_backup(filepath)
      
      try:
          df = pd.read_csv(filepath)
          
          # Create new row DataFrame
          new_row = pd.DataFrame([row_data])
          
          # Append the new row
          df = pd.concat([df, new_row], ignore_index=True)
          
          df.to_csv(filepath, index=False)
          self._validate_file_size(filepath)
          
          logger.info(f"Added row to CSV file: {filepath}")
          return {
              "success": True,
              "filename": filename,
              "row_added": row_data,
              "new_total_rows": len(df)
          }
      except Exception as e:
          logger.error(f"Failed to add row: {e}")
          raise

• csv_mcp_server/server.py:110-110 (registration)

  Registration of the 'add_row' tool via FastMCP @mcp.tool() decorator.

  @mcp.tool()

• csv_mcp_server/server.py:111-111 (schema)

  Input schema defined by function signature: filename (str), row_data (Dict[str, Any]); output Dict[str, Any].

  def add_row(filename: str, row_data: Dict[str, Any]) -> Dict[str, Any]: