工具返回

def create_image_message(self, image: str) -> ToolInvokeMessage:
    """
    Return an image URL message
    
    Dify will automatically download the image from the provided URL
    and display it to the user.
    
    Args:
        image: URL to an image file
        
    Returns:
        ToolInvokeMessage: Message object for the tool response
    """
    pass

from typing import Any

def create_variable_message(self, variable_name: str, variable_value: Any) -> ToolInvokeMessage:
    """
    Create a named variable for workflow integration
    
    For non-streaming output variables. If multiple instances with the 
    same name are created, the latest one overrides previous values.
    
    Args:
        variable_name: Name of the variable to create
        variable_value: Value of the variable (any Python data type)
        
    Returns:
        ToolInvokeMessage: Message object for the tool response
    """
    pass

identity:
  author: example_author
  name: example_tool
  label:
    en_US: Example Tool
    zh_Hans: 示例工具
    ja_JP: ツール例
    pt_BR: Ferramenta de exemplo
description:
  human:
    en_US: A simple tool that returns a name
    zh_Hans: 返回名称的简单工具
    ja_JP: 名前を返す簡単なツール
    pt_BR: Uma ferramenta simples que retorna um nome
  llm: A simple tool that returns a name variable
output_schema:
  type: object
  properties:
    name:
      type: string
      description: "The name returned by the tool"
    age:
      type: integer
      description: "The age returned by the tool"
    profile:
      type: object
      properties:
        interests:
          type: array
          items:
            type: string
        location:
          type: string

def run(self, inputs):
    # Process inputs and generate a name
    generated_name = "Alice"
    
    # Return the name as a variable that matches the output_schema
    return self.create_variable_message("name", generated_name)

import requests
from typing import Any

class WeatherForecastTool:
    def run(self, inputs: dict) -> Any:
        # Get location from inputs
        location = inputs.get("location", "London")
        
        try:
            # Call weather API (example only)
            weather_data = self._get_weather_data(location)
            
            # Create variables for workflow use
            self.create_variable_message("temperature", weather_data["temperature"])
            self.create_variable_message("conditions", weather_data["conditions"])
            self.create_variable_message("forecast", weather_data["forecast"])
            
            # Create a JSON message for data transmission
            self.create_json_message(weather_data)
            
            # Create an image message for the weather map
            self.create_image_message(weather_data["map_url"])
            
            # Return a formatted text response
            return self.create_text_message(
                f"Weather in {location}: {weather_data['temperature']}°C, {weather_data['conditions']}. "
                f"Forecast: {weather_data['forecast']}"
            )
            
        except Exception as e:
            # Handle errors gracefully
            return self.create_text_message(f"Error retrieving weather data: {str(e)}")
    
    def _get_weather_data(self, location: str) -> dict:
        # Mock implementation - in a real tool, this would call a weather API
        return {
            "location": location,
            "temperature": 22,
            "conditions": "Partly Cloudy",
            "forecast": "Sunny with occasional showers tomorrow",
            "map_url": "https://example.com/weather-map.png"
        }