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Dynamically selecting from multiple prompts

This notebook demonstrates how to use the RouterChain paradigm to create a chain that dynamically selects the prompt to use for a given input. Specifically we show how to use the MultiPromptChain to create a question-answering chain that selects the prompt which is most relevant for a given question, and then answers the question using that prompt.

import { MultiPromptChain } from "langchain/chains";
import { OpenAIChat } from "langchain/llms/openai";

const llm = new OpenAIChat();
const promptNames = ["physics", "math", "history"];
const promptDescriptions = [
  "Good for answering questions about physics",
  "Good for answering math questions",
  "Good for answering questions about history",
];
const physicsTemplate = `You are a very smart physics professor. You are great at answering questions about physics in a concise and easy to understand manner. When you don't know the answer to a question you admit that you don't know.

Here is a question:
{input}
`;
const mathTemplate = `You are a very good mathematician. You are great at answering math questions. You are so good because you are able to break down hard problems into their component parts, answer the component parts, and then put them together to answer the broader question.

Here is a question:
{input}`;

const historyTemplate = `You are a very smart history professor. You are great at answering questions about history in a concise and easy to understand manner. When you don't know the answer to a question you admit that you don't know.

Here is a question:
{input}`;

const promptTemplates = [physicsTemplate, mathTemplate, historyTemplate];

const multiPromptChain = MultiPromptChain.fromLLMAndPrompts(llm, {
  promptNames,
  promptDescriptions,
  promptTemplates,
});

const testPromise1 = multiPromptChain.call({
  input: "What is the speed of light?",
});

const testPromise2 = multiPromptChain.call({
  input: "What is the derivative of x^2?",
});

const testPromise3 = multiPromptChain.call({
  input: "Who was the first president of the United States?",
});

const [{ text: result1 }, { text: result2 }, { text: result3 }] =
  await Promise.all([testPromise1, testPromise2, testPromise3]);

console.log(result1, result2, result3);

API Reference: