一个预构建的编译图。
import { ChatOpenAI } from "@langchain/openai";
import { tool } from "@langchain/core/tools";
import { z } from "zod";
import { createReactAgent } from "@langchain/langgraph/prebuilt";
const model = new ChatOpenAI({
model: "gpt-4o",
});
const getWeather = tool((input) => {
if (["sf", "san francisco"].includes(input.location.toLowerCase())) {
return "It's 60 degrees and foggy.";
} else {
return "It's 90 degrees and sunny.";
}
}, {
name: "get_weather",
description: "Call to get the current weather.",
schema: z.object({
location: z.string().describe("Location to get the weather for."),
})
})
const agent = createReactAgent({ llm: model, tools: [getWeather] });
const inputs = {
messages: [{ role: "user", content: "what is the weather in SF?" }],
};
const stream = await agent.stream(inputs, { streamMode: "values" });
for await (const { messages } of stream) {
console.log(messages);
}
// Returns the messages in the state at each step of execution
创建一个依赖于使用工具调用的聊天模型的状态图代理。