langchain-fundamentals

Guide developers in building LangChain agents with create_agent, tools, and middleware.

Updated Aug 27, 2026
One-click install
npx skills add https://github.com/HyunjunJeon/SDS-AX-Advanced-2026-1 --skill langchain-fundamentals-hyunjunjeon
Or copy as Structured Prompt for Agent▼
Please help me install this Agent Skill.
Skill: langchain-fundamentals
Source: https://github.com/HyunjunJeon/SDS-AX-Advanced-2026-1/tree/main/Day-01/.agents/skills/langchain-fundamentals
Command: npx skills add https://github.com/HyunjunJeon/SDS-AX-Advanced-2026-1 --skill langchain-fundamentals-hyunjunjeon

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

Streamlines building robust LangChain agents by guiding how to use create_agent(), integrate tools, and apply middleware for human-in-the-loop and error handling.

Core Features & Use Cases

  • Guides how to create agents with create_agent(), configure tools, and manage state.
  • Demonstrates middleware patterns for human-in-the-loop approval and error handling.
  • Shows how to define tools with @tool and tool() for Python and TypeScript.
  • Provides practical examples for production-grade agent workflows.

Quick Start

Create a LangChain agent using create_agent(), wire a simple tool, and apply human-in-the-loop middleware.

Frequently Asked Questions about langchain-fundamentals

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

FAQPage Schema
How do I create a LangChain agent with create_agent?▼

To create a LangChain agent, use the create_agent() function to configure agent state, wire tools using @tool or tool() decorators, and apply middleware for production-ready workflows. It guides setup across Python and TypeScript.

Does this guide show how to add human-in-the-loop approval for LangChain agents?▼

Yes, it demonstrates middleware patterns specifically for human-in-the-loop approval. You configure middleware within the create_agent() setup to intercept agent actions and handle HITL workflows safely across Python and TypeScript environments.

Can I use create_agent to manage state and define tools in both Python and TypeScript?▼

Yes, create_agent supports state management and tool definitions in both Python and TypeScript. You define tools using @tool or tool() syntax, allowing you to configure production-grade agent workflows consistently across both languages.

What is the best way to handle errors in LangChain agent workflows?▼

The best way to handle errors in LangChain agent workflows is by applying middleware patterns. These patterns enforce safe usage by providing clear structures for error handling alongside human-in-the-loop logic within your create_agent() configuration.

Why use middleware patterns when building LangChain agents?▼

You use middleware patterns to build robust LangChain agents because they enforce safe usage with clear structures for human-in-the-loop approval, error handling, and memory management. This streamlines production-grade agent configuration.