@braintrust/langchain-js

[!WARNING] This package and all of its exports are deprecated and will stop being published after the next release. Use the LangChain integration in braintrust instead.

Installation

npm install braintrust
# or
yarn add braintrust
# or
pnpm add braintrust

Automatic instrumentation

For application-wide instrumentation, use the Braintrust runtime hook:

node --import braintrust/hook.mjs app.js

Braintrust also supports Vite, Webpack, esbuild, and Rollup. See the Braintrust SDK documentation for bundler setup.

Manual instrumentation

For scoped instrumentation, pass BraintrustLangChainCallbackHandler from braintrust through LangChain's callbacks option:

import { ChatOpenAI } from "@langchain/openai";
import { BraintrustLangChainCallbackHandler } from "braintrust";

const handler = new BraintrustLangChainCallbackHandler();

const model = new ChatOpenAI({
  callbacks: [handler],
});

const response = await model.invoke("Tell me a joke about bears", {
  callbacks: [handler],
});

setGlobalHandler does not have a direct replacement in braintrust. Use automatic instrumentation for application-wide coverage, or pass the handler explicitly for scoped instrumentation.

Documentation

• Braintrust docs: https://www.braintrust.dev/docs
• LangChain callback docs: https://js.langchain.com/docs/how_to/#callbacks