LangChain Security Basics

Overview

Essential security practices for LangChain applications: secrets management, prompt injection defense, safe tool execution, output validation, and audit logging.

1. Secrets Management

// NEVER hardcode API keys
// BAD: const apiKey = "sk-abc123...";

// GOOD: Environment variables with validation
import "dotenv/config";

function requireEnv(name: string): string {
  const value = process.env[name];
  if (!value) throw new Error(`Missing required env var: ${name}`);
  return value;
}