Add create_deep_agent option and LangSmith setup instructions

- Show both create_agent and create_deep_agent options in agent.py
- Add LangSmith signup link to README setup instructions

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

.env.example

@@ -1,7 +1,6 @@
 # API Keys
 OPENAI_API_KEY=your_openai_key_here
 
-# Optional: LangSmith tracing
 LANGSMITH_API_KEY=your_langsmith_key_here
 LANGCHAIN_TRACING_V2=true
 LANGCHAIN_PROJECT=music-support-bot

README.md

@@ -1,6 +1,6 @@
 # Music Store Customer Support Bot - Starter Code
 
-Simple starter code for building a customer support agent for the Chinook music store database using `create_agent()`.
+Simple starter code for building a customer support agent for the Chinook music store database using `create_agent()` or `create_deep_agent()`.
 
 ## Setup
 
@@ -9,8 +9,9 @@ Simple starter code for building a customer support agent for the Chinook music
 pip install -r requirements.txt
 pip install langgraph-cli
 
-# 2. Add your API key to .env
-# Edit OPENAI_API_KEY in the .env file
+# 2. Add your API keys to .env
+#    - OPENAI_API_KEY: https://platform.openai.com/api-keys
+#    - LANGSMITH_API_KEY: https://smith.langchain.com/ (sign up, then Settings > API Keys)
 
 # 3. Run Studio
 langgraph dev
@@ -29,7 +30,7 @@ take_home/
 ├── .env                   # Environment variables (add your API keys here)
 ├── .env.example           # Template
 └── src/
-    ├── agent.py           # Agent definition using create_agent()
+    ├── agent.py           # Agent definition
     ├── db.py              # Database connection (loads from GitHub)
     └── tools/
         ├── customer_tools.py # get_customer_orders tool

src/agent.py

@@ -1,19 +1,14 @@
-"""
-Music Store Customer Support Bot - Simple 2-Tool Agent
+"""Music Store Customer Support Bot"""
 
-Uses create_agent() with minimal tools for simplicity.
-"""
 import os
 from langchain_openai import ChatOpenAI
 from langchain.agents import create_agent
+from langchain.agents import create_deep_agent
 from src.tools.customer_tools import get_customer_orders
 from src.tools.music_tools import list_tracks_by_artist
 
-# Model configuration
 DEFAULT_MODEL = os.getenv("MODEL", "gpt-4o")
 
-
-# System prompt for the agent
 SYSTEM_PROMPT = """You are a helpful customer support agent for a music store.
 
 You can help customers with:
@@ -26,20 +21,16 @@ Important:
 - Be friendly, helpful, and professional
 - For questions outside these capabilities, politely explain what you can help with"""
 
+TOOLS = [get_customer_orders, list_tracks_by_artist]
+
 
 def build_agent():
-    """Build the customer support agent with 2 simple tools."""
+    """Build agent using create_agent."""
     model = ChatOpenAI(model=DEFAULT_MODEL, temperature=0)
+    return create_agent(model=model, tools=TOOLS, system_prompt=SYSTEM_PROMPT)
 
-    tools = [
-        get_customer_orders,    # View order history
-        list_tracks_by_artist   # Browse tracks by artist
-    ]
 
-    agent = create_agent(
-        model=model,
-        tools=tools,
-        system_prompt=SYSTEM_PROMPT
-    )
-
-    return agent
+# def build_agent():
+#     """Build agent using create_deep_agent."""
+#     model = ChatOpenAI(model=DEFAULT_MODEL, temperature=0)
+#     return create_deep_agent(model=model, tools=TOOLS, system_prompt=SYSTEM_PROMPT)