editor-mcp

Instructions

Implementation Reference

• src/text_editor/server.py:455-499 (handler)

  Implementation of the 'read' tool handler. Reads a range of lines (start to end) from the currently set file, validates the range, formats lines with numbers, and returns them in a structured dictionary. Handles errors like no file set or invalid ranges.

  async def read(start: int, end: int) -> Dict[str, Any]:
      """
      Read lines from the current file from start line to end line, returning them in a dictionary
      like {"lines":[[1,"text on first line"],[2,"text on second line"]]}. This makes it easier to find the precise lines to select for editing.
  
      Args:
          start (int, optional): Start line number
          end (int, optional): End line number
  
      Returns:
          dict: lines, start_line, end_line
      """
      result = {}
  
      if self.current_file_path is None:
          return {"error": "No file path is set. Use set_file first."}
  
      try:
          with open(self.current_file_path, "r", encoding="utf-8") as file:
              lines = file.readlines()
  
          if start < 1:
              return {"error": "start must be at least 1"}
          if end > len(lines):
              end = len(lines)
          if start > end:
              return {
                  "error": f"{start=} cannot be greater than {end=}. {len(lines)=}"
              }
  
          selected_lines = lines[start - 1 : end]
  
          formatted_lines = []
          for i, line in enumerate(selected_lines, start):
              formatted_lines.append((i, line.rstrip()))
  
          result["lines"] = formatted_lines
          result["start_line"] = start
          result["end_line"] = end
  
          return result
  
      except Exception as e:
          return {"error": f"Error reading file: {str(e)}"}