Topic
LangChain + OpenAI-Compatible Gateway Integration
14 posts on langchain + openai-compatible gateway integration — part of api integration on the n4n AI blog.
Using LangChain's fallback chains with n4n.ai's model routing
Set up LangChain fallback chains model routing with an OpenAI-compatible gateway to keep LLM pipelines resilient when providers rate-limit or degrade.
LangChain vs raw HTTP calls to OpenAI-compatible APIs
A pragmatic head-to-head: LangChain vs raw HTTP calls to OpenAI-compatible APIs across cost, latency, ergonomics, and ecosystem to guide your stack decision.
LangChain token usage tracking with an OpenAI-compatible gateway
Practical steps for LangChain token usage tracking with an OpenAI-compatible gateway: capture usage metadata, build callbacks, and verify token counts.
LangChain streaming callbacks with OpenAI-compatible APIs
A step-by-step guide to building LangChain streaming callbacks with OpenAI-compatible APIs, covering custom handlers, async flows, and usage metering.
LangChain retry and timeout config for gateway-routed LLM calls
Practical guide to configuring LangChain retry and timeout settings for LLM calls routed through an OpenAI-compatible gateway, with code and pitfalls.
LangChain model_name overrides for OpenAI-compatible gateways
Learn how to correctly set and override LangChain's model_name when routing through OpenAI-compatible gateways, with runnable code and verification steps.
LangChain LCEL chains with multi-provider model routing
Learn how to implement langchain lcel multi-provider routing with a single OpenAI-compatible endpoint, including LCEL chains, fallback, and verification.
LangChain agents with tool calling on OpenAI-compatible models
Hands-on tutorial for building LangChain tool-calling agents against OpenAI-compatible endpoints, with runnable Python code and production resilience patterns.
Debugging LangChain 429 errors with gateway-level rate limits
Step-by-step guide to diagnosing and fixing LangChain 429 error rate limits gateway issues by configuring fallback and client-side throttling.
Switching LangChain from OpenAI to Claude 3.5 via a gateway
Step-by-step guide to the langchain openai to claude 3.5 switch using an OpenAI-compatible gateway, with runnable code and verification tips for engineers.
LangChain JS streaming chat with n4n.ai's chat completions API
Hands-on tutorial for building langchain js streaming chat completions against an OpenAI-compatible gateway, with runnable Node.js code and expected output.
LangChain ChatOpenAI with a custom base_url for gateway routing
Learn how to point LangChain ChatOpenAI at a custom base_url gateway for model routing, fallback, and unified API access with runnable Python code.
Configuring LangChain to use n4n.ai as an OpenAI-compatible endpoint
Step-by-step langchain openai-compatible endpoint config to route LangChain calls through n4n.ai's 240+ model gateway with fallback and metering.
Building a LangChain RAG pipeline with n4n.ai's chat completions
Hands-on tutorial: build a LangChain RAG pipeline using OpenAI-compatible chat completions, with runnable code for retrieval-augmented generation.
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- Python + OpenAI-Compatible SDK Integration14
- Rate Limits, Retries & Backoff Strategies14
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