langchain

Orchestrate LLM applications with LCEL chains, LangGraph agents, and RAG pipelines.

40|6|Updated Jul 11, 2026
One-click install
npx skills add https://github.com/magnus919/agent-skills --skill langchain-magnus919
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: langchain
Source: https://github.com/magnus919/agent-skills/tree/main/langchain
Command: npx skills add https://github.com/magnus919/agent-skills --skill langchain-magnus919

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill requires langchain, langchain-core, langchain-openai, langchain-community, langserve, fastapi, uvicorn, and includes scripts (resource) and references (resource) components.

What problem does it solve?

This skill addresses the complexity of orchestrating LLM applications by providing a standardized, modular framework for building chains, agents, and RAG pipelines that are observable and production-ready.

Core Features & Use Cases

  • LCEL Composition: Build complex LLM workflows using the pipe operator for clean, readable, and modular code.
  • Agent Orchestration: Create tool-using agents powered by the LangGraph runtime for streaming, persistence, and state management.
  • Production Observability: Integrate LangSmith tracing to debug agent behavior, monitor latency, and evaluate performance in real-time.
  • Use Case: Quickly prototype a RAG-based customer support bot that retrieves documentation, uses tools to check order status, and logs all interactions for quality assurance.

Quick Start

Use the langchain skill to initialize a basic LCEL chain that prompts a model to answer a specific question.

Frequently Asked Questions about langchain

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I build production-ready LLM apps with LangChain?

Build production-ready LLM apps with LangChain by orchestrating modular components through LCEL chain composition, LangGraph agent creation, and RAG pipeline implementation for enterprise-grade AI scenarios.

What is the best way to create tool-using agents using LangGraph?

Create tool-using agents with LangGraph by leveraging its runtime for state management, streaming event handling, and persistent memory, enabling complex multi-step reasoning workflows.

How do I implement a RAG pipeline for an LLM application?

Implement a RAG pipeline using LCEL composition to connect retrieval components with language models, enabling applications like customer support bots to retrieve documentation and use external tools.

Can I integrate LangSmith tracing for LLM observability?

Integrate LangSmith tracing to achieve production observability, allowing you to debug agent behavior, monitor latency, and evaluate LLM performance in real-time.

Does LangChain support streaming event handling in FastAPI?

LangChain supports streaming event handling through LangServe and FastAPI integration, allowing you to deploy modular LCEL chains and LangGraph agents as production-ready APIs.

Why use LCEL composition for complex LLM workflows?

Use LCEL composition to build complex LLM workflows with the pipe operator, resulting in clean, readable, and modular code that supports framework-neutral evaluation and standardized integration.