LangChain SDK Patterns

Overview

Production-grade patterns every LangChain application should use: type-safe structured output, provider fallbacks, async batch processing, streaming, caching, and retry logic.

Pattern 1: Structured Output with Zod

import { ChatOpenAI } from "@langchain/openai";
import { ChatPromptTemplate } from "@langchain/core/prompts";
import { z } from "zod";