langgraph-python-quickstart

Scaffolds a minimal local LangGraph agent in Python following the official quickstart.

1.2k|90|Updated Jan 22, 2026
One-click install
npx skills add https://github.com/langchain-ai/langchain-skills --skill langgraph-python-quickstart
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: langgraph-python-quickstart
Source: https://github.com/langchain-ai/langchain-skills/tree/main/config/skills/langgraph-python-quickstart
Command: npx skills add https://github.com/langchain-ai/langchain-skills --skill langgraph-python-quickstart

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

Setting up a first LangGraph agent often involves guessing at APIs, hardcoded model choices, and cluttered project directories. This Skill walks through the official LangGraph Python quickstart so you get a working local agent with the correct current API and your preferred model provider.

Core Features & Use Cases

  • Official quickstart alignment: Fetches the live LangGraph quickstart docs and implements the calculator/math agent using the Graph API rather than relying on memorized APIs.
  • Model-agnostic setup: Prompts for a provider:model string (e.g. openai, anthropic, google_genai) and wires it via init_chat_model, with provider-specific constraints handled.
  • Clean local environment: Creates a dedicated directory, keeps the API key in a gitignored .env file, and installs only the required packages.
  • Use Case: You want to try LangGraph locally for the first time — the Skill scaffolds a new langgraph-agent directory, configures your chosen model, runs the example "Add 3 and 4.", and shows the output.

Quick Start

Ask your agent to scaffold a minimal local LangGraph agent in Python using the official quickstart with your preferred model provider.

Frequently Asked Questions about langgraph-python-quickstart

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

FAQPage Schema
How do I build a LangGraph agent in Python locally?

Follow the official LangGraph Python quickstart, which builds a calculator/math agent using the Graph API. Create a new directory, install the quickstart packages plus your model provider package, set the API key in a .env file, and run the example.

Which models can I use with a LangGraph agent?

LangGraph works with any LangChain chat model via init_chat_model using a provider:model string, such as openai:gpt-5.5, anthropic:claude-sonnet-5, or google_genai:gemini-2.5-flash-lite. For Claude Sonnet 5+, omit temperature, top_p, and top_k parameters.

Should I use the Graph API or Functional API in LangGraph?

The quickstart prefers the Graph API path over the Functional API unless you specifically ask otherwise. For a higher-level agent interface, use LangChain's create_agent instead of building the graph directly.

Do I need LangSmith or Tavily keys for the LangGraph quickstart?

No. The only secret required is your model provider's API key stored in a gitignored .env file. LangSmith and Tavily are optional and only added if you explicitly request them.

What are the next steps after the LangGraph quickstart?

After running the example successfully, move on to the langgraph-fundamentals material for deeper concepts. If you want a higher-level abstraction, switch to LangChain's create_agent API.