langchain-fundamentals

Build LangChain agents with create_agent(), middleware, and tool definitions.

7|1|Updated Mar 15, 2026
One-click install
npx skills add https://github.com/Harmeet10000/skills --skill langchain-fundamentals-harmeet10000
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: langchain-fundamentals
Source: https://github.com/Harmeet10000/skills/tree/main/skills/ai-ml/langchain-fundamentals
Command: npx skills add https://github.com/Harmeet10000/skills --skill langchain-fundamentals-harmeet10000

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

This skill helps developers rapidly assemble production-ready LangChain agents using create_agent(), define tools, and apply middleware for human-in-the-loop and error handling.

Core Features & Use Cases

  • Agent creation: Use create_agent() to manage the agent loop, tool execution, and state.
  • Tool definitions: Define tools with the @tool decorator (Python) or tool() (TypeScript) and expose clear descriptions for proper tool use.
  • Middleware patterns: Implement human-in-the-loop approvals, error handling, and custom hooks to control agent behavior.

Quick Start

Create an agent using create_agent() with a simple tool and a middleware setup to begin testing.

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 middleware for production workflows?

Build LangChain agents by using create_agent() to manage the agent loop and state, then apply middleware patterns for human-in-the-loop approvals and error handling to control automated workflows.

How does middleware work with LangChain agents for human-in-the-loop approvals?

Middleware intercepts the LangChain agent loop to enable human-in-the-loop approvals, error handling, and custom hooks, allowing developers to control tool execution and decision support flows before proceeding.

What is the best way to define tools for LangChain agents?

Define tools using the @tool decorator in Python or tool() in TypeScript, ensuring you provide clear descriptions for proper tool use by the agent during data retrieval and decision support tasks.

Can I use create_agent() for orchestrated data retrieval and automated workflows?

Yes, create_agent() manages the agent loop, tool execution, and state, making it suitable for teams needing orchestrated agents for data retrieval, decision support, and automated workflows.

Do I need external dependencies to implement error handling in LangChain agents?

No external dependencies are required; you implement error handling and custom hooks directly through middleware integration within the LangChain agent loop to control agent behavior.