• Create an agent that uses ReAct prompting.

    Parameters

    Returns Promise<AgentRunnableSequence<any, any>>

    A runnable sequence representing an agent. It takes as input all the same input variables as the prompt passed in does. It returns as output either an AgentAction or AgentFinish.

    import { AgentExecutor, createReactAgent } from "langchain/agents";
    import { pull } from "langchain/hub";
    import type { PromptTemplate } from "@langchain/core/prompts";

    import { OpenAI } from "@langchain/openai";

    // Define the tools the agent will have access to.
    const tools = [...];

    // Get the prompt to use - you can modify this!
    // If you want to see the prompt in full, you can at:
    // https://smith.langchain.com/hub/hwchase17/react
    const prompt = await pull<PromptTemplate>("hwchase17/react");

    const llm = new OpenAI({
    temperature: 0,
    });

    const agent = await createReactAgent({
    llm,
    tools,
    prompt,
    });

    const agentExecutor = new AgentExecutor({
    agent,
    tools,
    });

    const result = await agentExecutor.invoke({
    input: "what is LangChain?",
    });