Opik LangChain Integration

Seamlessly integrate Opik observability with your LangChain applications to trace, monitor, and debug your LLM chains, agents, and tools.

Features

• 🔍 Comprehensive Tracing: Automatically trace LLM calls, chains, tools, retrievers, and agents
• 📊 Hierarchical Visualization: View your LangChain execution as a structured trace with parent-child relationships
• 📝 Detailed Metadata Capture: Record model names, prompts, completions, usage statistics, and custom metadata
• 🚨 Error Handling: Capture and visualize errors at every step of your LangChain execution
• 🏷️ Custom Tagging: Add custom tags to organize and filter your traces

Installation

# npm
npm install opik-langchain

# yarn
yarn add opik-langchain

# pnpm
pnpm add opik-langchain

Requirements

• Node.js ≥ 18
• LangChain (@langchain/core ≥ 0.3.42)
• Opik SDK (automatically installed as a dependency)

Quick Start

import { OpikCallbackHandler } from "opik-langchain";
import { ChatOpenAI } from "@langchain/openai";

// Create the Opik callback handler
const opikHandler = new OpikCallbackHandler();

// Create your LangChain components with the handler
const llm = new ChatOpenAI({
  callbacks: [opikHandler],
});

// Run LLM
const response = await llm.invoke("Hello, how can you help me today?", {
  callbacks: [opikHandler],
});

// Optionally, ensure all traces are sent before your app terminates
await opikHandler.flushAsync();

Advanced Configuration

The OpikCallbackHandler constructor accepts the following options:

interface OpikCallbackHandlerOptions {
  // Optional array of tags to apply to all traces
  tags?: string[];

  // Optional metadata to include with all traces
  metadata?: Record<string, unknown>;

  // Optional project name for Opik
  projectName?: string;

  // Optional pre-configured Opik client
  client?: Opik;
}

Capturing Custom Metadata

You can pass custom metadata when invoking your chains:

const response = await chain.invoke(
  { input: "Tell me about AI" },
  {
    callbacks: [opikHandler],
    metadata: {
      userId: "user-123",
      sessionId: "session-456",
      requestId: "req-789",
    },
  }
);

Viewing Traces

To view your traces:

1. Sign in to your Comet account
2. Navigate to the Opik section
3. Select your project to view all traces
4. Click on a specific trace to see the detailed execution flow

Learn More

• Opik Documentation
• LangChain Documentation
• Opik TypeScript SDK

License

Apache 2.0