Agent Observability Demo

Simple LangGraph agent (Gemini + a mock weather tool), traced to LangSmith.

Setup

1. Copy .env.example to .env and fill in your keys.
2. python3 -m venv .venv
3. .venv/bin/pip install -r requirements.txt

Run the UI

.venv/bin/streamlit run app.py

Enter a query in the text box and click "Run agent".

Run in terminal

Case 1 — success (clean run, correct output):

.venv/bin/python agent.py

Case 2 — failure (tool raises an exception, visible as a failed trace in LangSmith):

.venv/bin/python agent.py --break

All runs appear in your LangSmith project (LANGCHAIN_PROJECT in .env).