LangChain JS Integration

@braintrust/langchain-js is deprecated as of v0.2.5 and will receive no further updates. Use auto-instrumentation to trace LangChain calls without changing your application code, or import BraintrustLangChainCallbackHandler from braintrust and attach it to each call yourself. See the LangChain integration guide for setup examples. setGlobalHandler has no direct replacement.

The @braintrust/langchain-js package provides integration between Braintrust and LangChain.js.

Installation

npm install @braintrust/langchain-js

pnpm add @braintrust/langchain-js

Quick start

import { BraintrustCallbackHandler } from "@braintrust/langchain-js";
import { ChatOpenAI } from "@langchain/openai";

// Create a callback handler
const handler = new BraintrustCallbackHandler();

// Use with any LangChain model
const llm = new ChatOpenAI({ callbacks: [handler] });

API Reference

Functions

setGlobalHandler

setGlobalHandler function. Deprecated, with no direct replacement. Use auto-instrumentation or pass the callback handler explicitly.

Classes

BraintrustCallbackHandler

A Braintrust tracer for LangChain.js that logs LLM calls, chains, and tools.

Source Code

For the complete source code and additional examples, visit the Braintrust JavaScript SDK repository.

Use the SDK

Reference

Related packages

LangChain JS Integration

Installation

Quick start

API Reference

Functions

setGlobalHandler

Classes

BraintrustCallbackHandler

Source Code

​Installation

​Quick start

​API Reference

​Functions

​setGlobalHandler

​Classes

​BraintrustCallbackHandler

​Source Code

Installation

Quick start

API Reference

Functions

setGlobalHandler

Classes

BraintrustCallbackHandler

Source Code