AWS Nova Canvas MCP Server

Instructions

Expand the image to create an outpainting.

Args:
    image_path: File path of the original image
    mask_image_path: File path of the mask image
    prompt: Text describing the content to be generated in the outpainting area
    negative_prompt: Text specifying attributes to exclude from generation
    outpainting_mode: Outpainting mode (DEFAULT or PRECISE)
    height: Output image height (pixels)
    width: Output image width (pixels)
    cfg_scale: Prompt matching degree (1-20)
    
Returns:
    Dict: Dictionary containing the file path of the outpainted image

Implementation Reference

• aws_nova_canvas_mcp/tools/outpainting.py:12-84 (handler)

  The main handler function for the 'outpainting' tool. It validates inputs, encodes images to base64, constructs a JSON payload for the Bedrock API (taskType: OUTPAINTING), calls generate_image, saves the result, and returns the image path.

  async def outpainting(
          image_path: str,
          mask_image_path: str,
          prompt: str,
          negative_prompt: str = "",
          outpainting_mode: str = "DEFAULT",
          height: int = 512,
          width: int = 512,
          cfg_scale: float = 8.0,
          output_path: str = None,
  ) -> Dict[str, Any]:
      """
      Expand the image to create an outpainting.
      
      Args:
          image_path: File path of the original image
          mask_image_path: File path of the mask image
          prompt: Text describing the content to be generated in the outpainting area
          negative_prompt: Text specifying attributes to exclude from generation
          outpainting_mode: Outpainting mode (DEFAULT or PRECISE)
          height: Output image height (pixels)
          width: Output image width (pixels)
          cfg_scale: Prompt matching degree (1-20)
          output_path: Absolute path to save the image
          
      Returns:
          Dict: Dictionary containing the file path of the outpainted image
      """
      try:
          # Validate outpainting mode
          if outpainting_mode not in ["DEFAULT", "PRECISE"]:
              raise ImageError("outpainting_mode must be 'DEFAULT' or 'PRECISE'.")
  
          # Read image file and encode to base64
          with open(image_path, "rb") as image_file:
              input_image = base64.b64encode(image_file.read()).decode('utf8')
  
          with open(mask_image_path, "rb") as mask_file:
              input_mask_image = base64.b64encode(mask_file.read()).decode('utf8')
  
          body = json.dumps({
              "taskType": "OUTPAINTING",
              "outPaintingParams": {
                  "text": prompt,
                  "negativeText": negative_prompt,
                  "image": input_image,
                  "maskImage": input_mask_image,
                  "outPaintingMode": outpainting_mode
              },
              "imageGenerationConfig": {
                  "numberOfImages": 1,
                  "height": height,
                  "width": width,
                  "cfgScale": cfg_scale
              }
          })
  
          # Generate image
          image_bytes = generate_image(body)
  
          # Save image
          image_info = save_image(image_bytes, output_path=output_path)
  
          # Generate result
          result = {
              "image_path": image_info["image_path"],
              "message": f"Outpainting completed successfully. Saved location: {image_info['image_path']}"
          }
  
          return result
  
      except Exception as e:
          raise McpError(f"Error occurred while outpainting: {str(e)}")

• aws_nova_canvas_mcp/server.py:33-33 (registration)

  Registration of the outpainting tool in the MCP server (currently commented out).

  # mcp.add_tool(outpainting)

• aws_nova_canvas_mcp/server.py:12-12 (registration)

  Import of the outpainting handler function into the server module.

  from .tools.outpainting import outpainting

• aws_nova_canvas_mcp/tools/outpainting.py:41-43 (schema)

  Input validation for the outpainting_mode parameter, enforcing 'DEFAULT' or 'PRECISE'.

  # Validate outpainting mode
  if outpainting_mode not in ["DEFAULT", "PRECISE"]:
      raise ImageError("outpainting_mode must be 'DEFAULT' or 'PRECISE'.")