Aseprite MCP Tools

Instructions

Implementation Reference

• aseprite_mcp/tools/palette.py:69-133 (handler)

  The main handler function for creating/replacing a palette in an Aseprite file using Lua script generation.

  async def create_palette(
      filename: str,
      colors: List[str],
      palette_name: Optional[str] = None
  ) -> str:
      """Create or replace a palette in an Aseprite file.
  
      Args:
          filename: Name of the Aseprite file to modify
          colors: List of hex color codes (e.g., ["FF0000", "00FF00", "0000FF"])
          palette_name: Optional name for the palette
      """
      try:
          # Validate inputs
          file_path = validate_file_path(filename, must_exist=True)
          
          if not colors:
              raise ValidationError("colors", colors, "Color list cannot be empty")
          
          if len(colors) > 256:
              raise ValidationError("colors", len(colors), "Palette cannot have more than 256 colors")
          
          # Validate all colors
          validated_colors = [validate_color(color) for color in colors]
          
          # Build Lua script
          builder = LuaBuilder()
          builder.open_sprite(str(file_path))
          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()
          
          # Create new palette
          builder.add_line('local palette = Palette(#spr.palettes > 0 and spr.palettes[1] or ' + str(len(validated_colors)) + ')')
          
          # Set colors
          for i, color in enumerate(validated_colors):
              r = int(color[0:2], 16)
              g = int(color[2:4], 16)
              b = int(color[4:6], 16)
              builder.add_line(f'palette:setColor({i}, Color{{r={r}, g={g}, b={b}, a=255}})')
          
          # Resize palette if needed
          builder.if_condition(f'#palette < {len(validated_colors)}')
          builder.add_line(f'palette:resize({len(validated_colors)})')
          builder.end_if()
          
          # Set palette
          builder.add_line('spr:setPalette(palette)')
          
          builder.save_sprite()
          
          # Execute script
          cmd = get_command()
          success, output = cmd.execute_lua_script(builder.build())
          
          return f"Palette with {len(validated_colors)} colors created successfully in {file_path}"
          
      except (ValidationError, AsepriteError) as e:
          return f"Failed to create palette: {e}"
      except Exception as e:
          return f"Unexpected error: {e}"