Image Processing MCP Server

Instructions

Implementation Reference

• tools/color_adjust.py:209-281 (handler)

  Core asynchronous handler function that implements the opacity adjustment logic by modifying the alpha channel of each pixel in the image.
  async def adjust_opacity(image_source: str, opacity: float) -> list[TextContent]: """ 调整图片不透明度 Args: image_source: 图片数据（base64编码）或文件路径 opacity: 不透明度值（0.0-1.0） Returns: 调整后的图片数据 """ try: # 验证参数 if not image_source: raise ValidationError("图片数据不能为空") if not validate_numeric_range(opacity, 0.0, 1.0): raise ValidationError(f"不透明度值必须在0.0-1.0范围内: {opacity}") # 加载图片 image = processor.load_image(image_source) original_mode = image.mode # 确保图片有alpha通道 if image.mode != 'RGBA': image = image.convert('RGBA') # 获取图片数据 data = image.getdata() # 调整alpha通道 new_data = [] for item in data: # item是(R, G, B, A)元组 r, g, b, a = item # 计算新的alpha值 new_alpha = int(a * opacity) new_data.append((r, g, b, new_alpha)) # 创建新图片 opacity_image = Image.new('RGBA', image.size) opacity_image.putdata(new_data) # 输出处理后的图片 output_info = processor.output_image(opacity_image, "opacity") result = { "success": True, "message": f"不透明度调整成功: {opacity}", "data": { **output_info, "opacity_value": opacity, "original_mode": original_mode, "new_mode": opacity_image.mode, "size": image.size } } return [TextContent(type="text", text=json.dumps(result, ensure_ascii=False))] except ValidationError as e: error_result = { "success": False, "error": f"参数验证失败: {str(e)}" } return [TextContent(type="text", text=json.dumps(error_result, ensure_ascii=False))] except Exception as e: error_result = { "success": False, "error": f"不透明度调整失败: {str(e)}" } return [TextContent(type="text", text=json.dumps(error_result, ensure_ascii=False))]
• main.py:473-487 (registration)

  MCP tool registration using FastMCP's @mcp.tool() decorator. Defines input schema via Annotated fields and delegates execution to the core handler.
  @mcp.tool() def adjust_opacity( image_source: Annotated[str, Field(description="图片源，可以是文件路径或base64编码的图片数据")], opacity: Annotated[float, Field(description="不透明度，范围 0.0-1.0，0.0为完全透明，1.0为完全不透明", ge=0.0, le=1.0)] ) -> str: """调整图片不透明度""" try: result = safe_run_async(color_adjust_opacity(image_source, opacity)) return result[0].text except Exception as e: return json.dumps({ "success": False, "error": f"调整不透明度失败: {str(e)}" }, ensure_ascii=False, indent=2)
• tools/color_adjust.py:139-158 (schema)

  JSON schema definition for the adjust_opacity tool input, used within get_color_adjust_tools() function (though registration uses pydantic schema).
  Tool( name="adjust_opacity", description="调整图片不透明度", inputSchema={ "type": "object", "properties": { "image_source": { "type": "string", "description": "图片数据（base64编码）或文件路径" }, "opacity": { "type": "number", "description": "不透明度值（0.0-1.0，0.0为完全透明，1.0为完全不透明）", "minimum": 0.0, "maximum": 1.0 } }, "required": ["image_source", "opacity"] } )