---
title: "Using OpenRouter With LangChain: ChatOpenRouter Setup Guide"
source: "OpenRouter：Announcements（RSS）"
source_tier: "t1"
url: "https://openrouter.ai/blog/tutorials/langchain-chatopenrouter-setup/"
permalink: "https://feed.astralor.com/items/itm_043db935aff40b65a551fb16"
published: "2026-07-29T00:00:00.000Z"
score: 78
channel: "tech"
tags: ["ChatOpenRouter","LangChain","OpenRouter","Model Ensembles"]
---

# Using OpenRouter With LangChain: ChatOpenRouter Setup Guide

## AI commentary

> If you want to flexibly call multiple large models in your LangChain project without being tied to API keys and providers, this tutorial is for you. It encapsulates the most critical configuration and exception handling, and can switch models in seconds. Worth bookmarking for all AI app developers.

## At a glance

This guide details how to wire OpenRouter into LangChain using the ChatOpenRouter class, covering installation, model string configuration, streaming, structured output, and provider fallbacks. Complete code examples are included to help developers quickly call multiple models on OpenRouter within LangChain applications.

## Key points

- Install ChatOpenRouter and set up the LangChain environment
- Configure model strings (e.g., openai/gpt-4o, anthropic/claude-3) for multi-model calling
- Support streaming output and structured output (JSON mode)
- Built-in provider fallback to improve availability

## Full text

Wire OpenRouter into LangChain with ChatOpenRouter: install, model strings, streaming, structured output, and provider fallbacks. Code included.

---

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