Stuff

The stuff documents chain ("stuff" as in "to stuff" or "to fill") is the most straightforward of the document chains. It takes a list of documents, inserts them all into a prompt and passes that prompt to an LLM.

This chain is well-suited for applications where documents are small and only a few are passed in for most calls.

Here's how it looks in practice:

tip

See this section for general instructions on installing integration packages.

npm

npm install @langchain/openai

Yarn

yarn add @langchain/openai

pnpm

pnpm add @langchain/openai

import { OpenAI } from "@langchain/openai";
import { loadQAStuffChain } from "langchain/chains";
import { Document } from "@langchain/core/documents";

// This first example uses the `StuffDocumentsChain`.
const llmA = new OpenAI({});
const chainA = loadQAStuffChain(llmA);
const docs = [
  new Document({ pageContent: "Harrison went to Harvard." }),
  new Document({ pageContent: "Ankush went to Princeton." }),
];
const resA = await chainA.invoke({
  input_documents: docs,
  question: "Where did Harrison go to college?",
});
console.log({ resA });
// { resA: { text: ' Harrison went to Harvard.' } }

API Reference:

• OpenAI from @langchain/openai
• loadQAStuffChain from langchain/chains
• Document from @langchain/core/documents