Lagent & AgentLego 智能体应用搭建

一、概述

Lagent 是一个轻量级开源智能体框架，旨在让用户可以高效地构建基于大语言模型的智能体。同时它也提供了一些典型工具以增强大语言模型的能力。

AgentLego 是一个提供了多种开源工具 API 的多模态工具包，旨在像是乐高积木一样，让用户可以快速简便地拓展自定义工具，从而组装出自己的智能体。

两者关系

安装环境：

Lagent：https://lagent.readthedocs.io/zh-cn/latest/get_started/install.html
AgentLego：https://agentlego.readthedocs.io/zh-cn/latest/get_started.html

二、Lagent

2.1 Lagent Web Demo

使用LMDeploy部署api_server，并启动Lagent Web Demo。映射到本地端口访问

使用arxiv插件搜索文章

2.2 使用Lagent自定义工具

https://lagent.readthedocs.io/zh-cn/latest/tutorials/action.html
步骤：

继承 BaseAction 类
实现简单工具的 run 方法；或者实现工具包内每个子工具的功能
简单工具的 run 方法可选被 tool_api 装饰；工具包内每个子工具的功能都需要被 tool_api 装饰

下面我们将实现一个调用和风天气 API 的工具以完成实时天气查询的功能。

import json
import os
import requests
from typing import Optional, Type

from lagent.actions.base_action import BaseAction, tool_api
from lagent.actions.parser import BaseParser, JsonParser
from lagent.schema import ActionReturn, ActionStatusCode

class WeatherQuery(BaseAction):
    """Weather plugin for querying weather information."""
    
    def __init__(self,
                 key: Optional[str] = None,
                 description: Optional[dict] = None,
                 parser: Type[BaseParser] = JsonParser,
                 enable: bool = True) -> None:
        super().__init__(description, parser, enable)
        key = os.environ.get('WEATHER_API_KEY', key)
        if key is None:
            raise ValueError(
                'Please set Weather API key either in the environment '
                'as WEATHER_API_KEY or pass it as `key`')
        self.key = key
        self.location_query_url = 'https://geoapi.qweather.com/v2/city/lookup'
        self.weather_query_url = 'https://devapi.qweather.com/v7/weather/now'

    @tool_api
    def run(self, query: str) -> ActionReturn:
        """一个天气查询API。可以根据城市名查询天气信息。
        
        Args:
            query (:class:`str`): The city name to query.
        """
        tool_return = ActionReturn(type=self.name)
        status_code, response = self._search(query)
        if status_code == -1:
            tool_return.errmsg = response
            tool_return.state = ActionStatusCode.HTTP_ERROR
        elif status_code == 200:
            parsed_res = self._parse_results(response)
            tool_return.result = [dict(type='text', content=str(parsed_res))]
            tool_return.state = ActionStatusCode.SUCCESS
        else:
            tool_return.errmsg = str(status_code)
            tool_return.state = ActionStatusCode.API_ERROR
        return tool_return
    
    def _parse_results(self, results: dict) -> str:
        """Parse the weather results from QWeather API.
        
        Args:
            results (dict): The weather content from QWeather API
                in json format.
        
        Returns:
            str: The parsed weather results.
        """
        now = results['now']
        data = [
            f'数据观测时间: {now["obsTime"]}',
            f'温度: {now["temp"]}°C',
            f'体感温度: {now["feelsLike"]}°C',
            f'天气: {now["text"]}',
            f'风向: {now["windDir"]}，角度为 {now["wind360"]}°',
            f'风力等级: {now["windScale"]}，风速为 {now["windSpeed"]} km/h',
            f'相对湿度: {now["humidity"]}',
            f'当前小时累计降水量: {now["precip"]} mm',
            f'大气压强: {now["pressure"]} 百帕',
            f'能见度: {now["vis"]} km',
        ]
        return '\n'.join(data)

    def _search(self, query: str):
        # get city_code
        try:
            city_code_response = requests.get(
                self.location_query_url,
                params={'key': self.key, 'location': query}
            )
        except Exception as e:
            return -1, str(e)
        if city_code_response.status_code != 200:
            return city_code_response.status_code, city_code_response.json()
        city_code_response = city_code_response.json()
        if len(city_code_response['location']) == 0:
            return -1, '未查询到城市'
        city_code = city_code_response['location'][0]['id']
        # get weather
        try:
            weather_response = requests.get(
                self.weather_query_url,
                params={'key': self.key, 'location': city_code}
            )
        except Exception as e:
            return -1, str(e)
        return weather_response.status_code, weather_response.json()

获取和风天气API_KEY
https://dev.qweather.com/docs/api/
同样地开启api_server和lagent

天气助手

三、AgentLego

使用mmdet算法库中的RTMDet-Large模型
目标检测工具脚本：

import re

import cv2
from agentlego.apis import load_tool

# load tool
tool = load_tool('ObjectDetection', device='cuda')

# apply tool
visualization = tool('/root/agent/road.jpg')
print(visualization)

# visualize
image = cv2.imread('/root/agent/road.jpg')

preds = visualization.split('\n')
pattern = r'(\w+) \((\d+), (\d+), (\d+), (\d+)\), score (\d+)'

for pred in preds:
    name, x1, y1, x2, y2, score = re.match(pattern, pred).groups()
    x1, y1, x2, y2, score = int(x1), int(y1), int(x2), int(y2), int(score)
    cv2.rectangle(image, (x1, y1), (x2, y2), (0, 255, 0), 1)
    cv2.putText(image, f'{name} {score}', (x1, y1), cv2.FONT_HERSHEY_SIMPLEX, 0.8, (0, 255, 0), 1)

cv2.imwrite('/root/agent/road_detection_direct.jpg', image)

demo

部署在应用中

3.3 自定义工具

使用MagicMakerImageGeneration 工具

油画

第六节 Agent