MCP Python Interpreter

Instructions

Write content to a file.

Args:
    file_path: Path to the file to write
    content: Content to write
    overwrite: Whether to overwrite if exists

Implementation Reference

• mcp_python_interpreter/server.py:767-803 (handler)

  The main handler function for the 'write_file' tool, decorated with @mcp.tool() for registration in the MCP framework. It handles writing string content to a file path relative to the working directory, with security checks, overwrite option, directory creation, and detailed success/error responses.

  @mcp.tool()
  def write_file(
      file_path: str,
      content: str,
      overwrite: bool = False
  ) -> str:
      """
      Write content to a file.
      
      Args:
          file_path: Path to the file to write
          content: Content to write
          overwrite: Whether to overwrite if exists
      """
      path = Path(file_path)
      if path.is_absolute():
          if not is_path_allowed(path):
              return f"Access denied: Can only write files in working directory: {WORKING_DIR}"
      else:
          path = WORKING_DIR / path
      
      try:
          if path.exists() and not overwrite:
              return f"File '{path}' exists. Use overwrite=True to replace."
          
          path.parent.mkdir(parents=True, exist_ok=True)
          
          with open(path, 'w', encoding='utf-8') as f:
              f.write(content)
              f.flush()
              os.fsync(f.fileno())
          
          file_size_kb = path.stat().st_size / 1024
          return f"Successfully wrote to {path}. Size: {file_size_kb:.2f} KB"
      
      except Exception as e:
          return f"Error writing file: {str(e)}"