Mode Manager MCP

Instructions

Implementation Reference

• src/mode_manager_mcp/tools/chatmode_tools.py:137-158 (handler)

  The MCP tool handler function that executes the 'update_chatmode' logic. It constructs frontmatter from optional inputs and calls the ChatModeManager's update method.

  def update_chatmode(
      filename: Annotated[str, "The filename of the chatmode to update (with or without extension)"],
      description: Annotated[Optional[str], "Optional new description for the chatmode"] = None,
      content: Annotated[Optional[str], "Optional new content for the chatmode"] = None,
      tools: Annotated[Optional[str], "Optional new comma-separated list of tool names"] = None,
  ) -> str:
      """Update an existing VS Code .chatmode.md file with new description, content, or tools."""
      if read_only:
          return "Error: Server is running in read-only mode"
      try:
          frontmatter = {}
          if description is not None:
              frontmatter["description"] = description
          if isinstance(tools, str):
              frontmatter["tools"] = tools
          success = chatmode_manager.update_chatmode(filename, frontmatter if frontmatter else None, content)
          if success:
              return f"Successfully updated VS Code chatmode: {filename}"
          else:
              return f"Failed to update VS Code chatmode: {filename}"
      except Exception as e:
          return f"Error updating VS Code chatmode '{filename}': {str(e)}"

• src/mode_manager_mcp/chatmode_manager.py:202-246 (helper)

  Core helper method in ChatModeManager that performs the actual file update by merging new frontmatter/content with existing and writing with backup.

  def update_chatmode(
      self,
      filename: str,
      frontmatter: Optional[Dict[str, Any]] = None,
      content: Optional[str] = None,
  ) -> bool:
      """
      Update an existing chatmode file.
  
      Args:
          filename: Name of the .chatmode.md file
          frontmatter: New frontmatter (optional)
          content: New content (optional)
  
      Returns:
          True if successful
  
      Raises:
          FileOperationError: If file cannot be updated
      """
      # Ensure filename has correct extension
      if not filename.endswith(".chatmode.md"):
          filename += ".chatmode.md"
  
      file_path = self.prompts_dir / filename
  
      if not file_path.exists():
          raise FileOperationError(f"Chatmode file not found: {filename}")
  
      try:
          # Read current content
          current_frontmatter, current_content = parse_frontmatter_file(file_path)
  
          # Use provided values or keep current ones
          new_frontmatter = frontmatter if frontmatter is not None else current_frontmatter
          new_content = content if content is not None else current_content
  
          success = write_frontmatter_file(file_path, new_frontmatter, new_content, create_backup=True)
          if success:
              logger.info(f"Updated chatmode file with backup: {filename}")
          return success
  
      except Exception as e:
          raise FileOperationError(f"Error updating chatmode file {filename}: {e}")

• src/mode_manager_mcp/tools/chatmode_tools.py:117-136 (schema)

  The @app.tool decorator defining the tool schema, including input parameter descriptions and return description.

  @app.tool(
      name="update_chatmode",
      description="Update an existing VS Code .chatmode.md file with new description, content, or tools.",
      tags={"public", "chatmode"},
      annotations={
          "idempotentHint": False,
          "readOnlyHint": False,
          "title": "Update Chatmode",
          "parameters": {
              "filename": "The filename of the chatmode to update. If .chatmode.md extension is not provided, it will be added automatically.",
              "description": "Optional new description for the chatmode. If not provided, the existing description will be kept.",
              "content": "Optional new content for the chatmode. If not provided, the existing content will be kept.",
              "tools": "Optional new comma-separated list of tool names. If not provided, the existing tools will be kept.",
          },
          "returns": "Returns a success message if the chatmode was updated, or an error message if the operation failed.",
      },
      meta={
          "category": "chatmode",
      },
  )

• src/mode_manager_mcp/simple_server_new.py:102-102 (registration)

  Top-level registration call to register_all_tools(), which includes register_chatmode_tools() defining the update_chatmode tool.

  register_all_tools()