langgraph-python-quickstart
About langgraph-python-quickstart
A quickstart skill for new LangGraph Python projects. It directs implementation to the current official docs and a calculator agent example, with minimal local setup and a model chosen by the user.
Key features
- 01Ask for a model provider and model
- 02Prefer the Graph API
- 03Create the project in a new directory
- 04Configure only the model API key
- 05Run the example and show its output
Use cases
- 01Start a LangGraph Python agent project
- 02Configure a chat model chosen by the user
- 03Check that a calculator agent handles a request
Install
Copy the command and run it in a terminal.
npx skills add https:/ / github.com/ langchain-ai/ langchain-skills --skill langgraph-python-quickstartAfter installing, type/langgraph-python-quickstartin Claude Code to confirm it loaded.
Details
From the project READMELangGraph Python quickstart
Follow the live docs — do not invent an alternate API from memory:
https://docs.langchain.com/oss/python/langgraph/quickstart
Fetch that page (Docs MCP or HTTP) and implement what it shows (calculator / math agent with the Graph API). Prefer the Graph API path over the Functional API unless the user asks otherwise. Skip IPython graph visualization.
Local setup constraints
Apply these on top of the quickstart (they keep setup minimal and model-agnostic):
-
Ask which provider/model to use. Showcase that LangGraph works with any LangChain chat model. Suggested prompt:
Which model should this agent use? Pass a
provider:modelstring — e.g.openai:gpt-5.5,anthropic:claude-sonnet-5,google_genai:gemini-2.5-flash-lite. Default if you're unsure:anthropic:claude-sonnet-5.The docs often hardcode Anthropic — replace with
init_chat_model("<MODEL>")(or equivalent) using their choice. If using Claude Sonnet 5+, omittemperature/top_p/top_k(unsupported). -
Create a new directory (e.g.
langgraph-agent/) and do all work there — do not pollute the open project. -
Only secret: the provider API key in
.env(gitignored). No LangSmith / Tavily unless they ask. Prefer they edit.envthemselves — don't paste keys into chat. -
Install packages from the quickstart plus the provider package for their model.
-
Run the example (e.g. “Add 3 and 4.”), show output, then stop. Point to
langgraph-fundamentalsfor next steps. For a higher-level agent API, use LangChaincreate_agentinstead.