Aseprite MCP Tools

Instructions

Implementation Reference

• aseprite_mcp/tools/drawing.py:112-145 (handler)

  The draw_rectangle tool handler function in drawing.py. It validates inputs, constructs a Lua script using LuaBuilder, and executes it via Aseprite.

  async def draw_rectangle(filename: str, x: int, y: int, width: int, height: int, color: str = "#000000", fill: bool = False) -> str:
      """Draw a rectangle on the canvas.
  
      Args:
          filename: Name of the Aseprite file to modify
          x: Top-left x coordinate
          y: Top-left y coordinate
          width: Width of the rectangle
          height: Height of the rectangle
          color: Hex color code (default: "#000000")
          fill: Whether to fill the rectangle (default: False)
      """
      try:
          # Validate inputs
          file_path = validate_file_path(filename, must_exist=True)
          color = validate_color(color)
          
          if width < 1:
              raise ValidationError("width", width, "Width must be at least 1")
          if height < 1:
              raise ValidationError("height", height, "Height must be at least 1")
          
          # Build Lua script
          builder = LuaBuilder()
          builder.add_line('local spr = app.activeSprite')
          builder.if_condition('not spr')
          builder.add_line('error("No active sprite")')
          builder.end_if()
          builder.add_line()
          
          builder.begin_transaction()
          builder.draw_rectangle(x, y, width, height, color, fill)
          builder.end_transaction()
          builder.save_sprite()