Deep Agents Code Review

When reviewing Deep Agents code, check for these categories of issues.

Critical Issues

1. Missing Checkpointer with interrupt_on

# BAD - interrupt_on without checkpointer
agent = create_deep_agent(
    tools=[send_email],
    interrupt_on={"send_email": True},
    # No checkpointer! Interrupts will fail
)

# GOOD - checkpointer required for interrupts
from langgraph.checkpoint.memory import InMemorySaver