Session State Advanced

1"""
2Session State Advanced
3=============================
4
5Session State Advanced.
6"""
7
8from textwrap import dedent
9
10from kern.agent import Agent
11from kern.db.sqlite import SqliteDb
12from kern.models.openai import OpenAIResponses
13from kern.run import RunContext
14
15
16# Define tools to manage our shopping list
17def add_item(run_context: RunContext, item: str) -> str:
18    """Add an item to the shopping list and return confirmation."""
19    # Add the item if it's not already in the list
20    if run_context.session_state is None:
21        run_context.session_state = {}
22
23    if item.lower() not in [
24        i.lower() for i in run_context.session_state["shopping_list"]
25    ]:
26        run_context.session_state["shopping_list"].append(item)  # type: ignore
27        return f"Added '{item}' to the shopping list"
28    else:
29        return f"'{item}' is already in the shopping list"
30
31
32def remove_item(run_context: RunContext, item: str) -> str:
33    """Remove an item from the shopping list by name."""
34    if run_context.session_state is None:
35        run_context.session_state = {}
36
37    # Case-insensitive search
38    for i, list_item in enumerate(run_context.session_state["shopping_list"]):
39        if list_item.lower() == item.lower():
40            run_context.session_state["shopping_list"].pop(i)
41            return f"Removed '{list_item}' from the shopping list"
42
43    return f"'{item}' was not found in the shopping list"
44
45
46def list_items(run_context: RunContext) -> str:
47    """List all items in the shopping list."""
48    if run_context.session_state is None:
49        run_context.session_state = {}
50
51    shopping_list = run_context.session_state["shopping_list"]
52
53    if not shopping_list:
54        return "The shopping list is empty."
55
56    items_text = "\n".join([f"- {item}" for item in shopping_list])
57    return f"Current shopping list:\n{items_text}"
58
59
60# Create a Shopping List Manager Agent that maintains state
61# ---------------------------------------------------------------------------
62# Create Agent
63# ---------------------------------------------------------------------------
64agent = Agent(
65    model=OpenAIResponses(id="gpt-5-mini"),
66    # Initialize the session state with an empty shopping list (default session state for all sessions)
67    session_state={"shopping_list": []},
68    db=SqliteDb(db_file="tmp/example.db"),
69    tools=[add_item, remove_item, list_items],
70    # You can use variables from the session state in the instructions
71    instructions=dedent("""\
72        Your job is to manage a shopping list.
73
74        The shopping list starts empty. You can add items, remove items by name, and list all items.
75
76        Current shopping list: {shopping_list}
77    """),
78    markdown=True,
79)
80
81# ---------------------------------------------------------------------------
82# Run Agent
83# ---------------------------------------------------------------------------
84if __name__ == "__main__":
85    # Example usage
86    agent.print_response("Add milk, eggs, and bread to the shopping list", stream=True)
87    print(f"Session state: {agent.get_session_state()}")
88
89    agent.print_response("I got bread", stream=True)
90    print(f"Session state: {agent.get_session_state()}")
91
92    agent.print_response("I need apples and oranges", stream=True)
93    print(f"Session state: {agent.get_session_state()}")
94
95    agent.print_response("whats on my list?", stream=True)
96    print(f"Session state: {agent.get_session_state()}")
97
98    agent.print_response(
99        "Clear everything from my list and start over with just bananas and yogurt",
100        stream=True,
101    )
102    print(f"Session state: {agent.get_session_state()}")

1# Clone and setup repo
2git clone https://github.com/kern-ai/kern.git
3cd kern/cookbook/02_agents/05_state_and_session
4
5# Create and activate virtual environment
6./scripts/demo_setup.sh
7source .venvs/demo/bin/activate
8
9python session_state_advanced.py