langchain-fundamentals

Implement create_agent patterns with middleware for human-in-the-loop control.

8|Updated Jul 26, 2026
One-click install
npx skills add https://github.com/joonlab/joonlab-claudecode-setting-for-share --skill langchain-fundamentals-joonlab
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: langchain-fundamentals
Source: https://github.com/joonlab/joonlab-claudecode-setting-for-share/tree/main/claude/skills/langchain-fundamentals
Command: npx skills add https://github.com/joonlab/joonlab-claudecode-setting-for-share --skill langchain-fundamentals-joonlab

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill requires langchain, @langchain/core, @langchain/langgraph, zod.

What problem does it solve?

This skill addresses the complexity of building reliable AI agents by providing standardized patterns for tool definition, state management, and human-in-the-loop control.

Core Features & Use Cases

  • Standardized Agent Creation: Uses the recommended create_agent pattern for consistent loop and tool execution.
  • Persistence & Memory: Implements MemorySaver checkpointers to maintain conversation state across multiple invocations.
  • Middleware Control: Provides patterns for human-in-the-loop approval and custom error handling to ensure production safety.

Quick Start

Use the langchain-fundamentals skill to initialize a new agent with a memory checkpointer and a custom tool for your specific task.

Frequently Asked Questions about langchain-fundamentals

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

FAQPage Schema
How do I build LangChain agents with persistent memory across multiple invocations?

Build LangChain agents with persistent memory by implementing MemorySaver checkpointers to maintain conversation state across multiple invocations. This approach ensures robust stateful AI agents retain context reliably throughout continuous interactions.

What is the best way to add human-in-the-loop approval to LangGraph agent workflows?

Add human-in-the-loop approval to LangGraph workflows by applying middleware control patterns for custom error handling and production safety. This middleware intercepts agent execution to enforce human approval before critical tool execution.

How do I enforce structured output validation and recursion limits in LangChain agents?

Enforce structured output validation and recursion limits in LangChain agents by using the standardized create_agent pattern. This pattern applies Zod schema validation and sets recursion boundaries to prevent infinite agent loops during tool execution.

Does LangChain work with Zod for structured output validation in production agents?

LangChain works with Zod to provide structured output validation in production agents. This integration ensures reliable tool execution by validating agent responses against defined schemas before returning results to the user.

Why does my LangChain agent loop infinitely during tool execution?

LangChain agents loop infinitely during tool execution when recursion limits are not configured. Prevent this by implementing the create_agent pattern with built-in recursion boundaries and custom error handling middleware for production safety.