Agentspace Agent Session

[mscdw]

When using an Agent Engine Agent registered in Agentspace, how are Sessions handled? How can the Agent determine the user_id and determine if a new or existing chat is being used?

[adk-bot]

Response from ADK Answering Agent (experimental, answer may be inaccurate)

TLDR: In the Google ADK, session management is handled by a SessionService. To determine the user_id and whether a chat is new or existing, you should create a unique session for each user conversation. The user_id is passed when creating a session and is used to identify the user associated with that session. You can differentiate between a new and existing chat by managing session IDs on your application's side.

---

Here is a more detailed explanation:

When building agents with the ADK, the Session object is the key to managing conversation history and state for a specific user interaction. Here’s how you can handle sessions, user IDs, and new vs. existing chats:

Session Management with SessionService

The ADK provides a SessionService to manage the lifecycle of sessions, which includes creating, retrieving, and updating them. [4, 5] For local development and testing, you can use the InMemorySessionService, but for production, you should use a persistent service like VertexAiSessionService especially when deploying to Agent Engine. [5, 14]

Identifying Users with user_id

When a user starts a conversation, you should create a session for them, and at that time, you provide a user_id. [1] This user_id is then associated with that session and can be accessed throughout the conversation. [4]

Here is an example of how to create a session with a user_id:

from google.adk.runners import InMemoryRunner
from google.adk.sessions import InMemorySessionService

# Create a SessionService
session_service = InMemorySessionService()

# Define your agent and app name
# root_agent = ...
# APP_NAME = "my-agent-app"

# When a user starts a conversation, create a session for them
user_id = "some_unique_user_id"  # This should be a unique identifier for the user
session = await session_service.create_session(
    app_name=APP_NAME,
    user_id=user_id
)

The user_id is then passed in API requests to identify the user, for example: /apps/{app_name}/users/{user_id}/sessions/{session_id}. [1, 2]

Distinguishing Between New and Existing Chats

Your application is responsible for determining if a conversation is new or existing. You can do this by managing session IDs.

• New Chat: When a user starts a new conversation, your application should call session_service.create_session(), which will generate a new unique session ID. You can then store this session ID on the client-side (e.g., in local storage or a cookie) to reuse it for subsequent requests in the same conversation. [4]
• Existing Chat: When a user returns, your application can check if a session ID is already stored for them. If so, you can use that session ID to retrieve the existing session and continue the conversation. The SessionService is used to resume existing conversations using the session ID.

By managing session IDs on your application's side, you can effectively distinguish between new and existing chats and maintain the context of each conversation.

[1] https://google.github.io/adk-docs/streaming/custom-streaming/
[2] https://google.github.io/adk-docs/get-started/testing/
[4] https://google.github.io/adk-docs/sessions/session/
[5] https://google.github.io/adk-docs/sessions/
[14] https://google.github.io/adk-docs/deploy/agent-engine/

[mscdw]

thanks @adk-bot. Here's some additional info.

Problem Statement: Enabling User-Specific Memory and Session Management for an Agent Invoked via Agent Space

1. Context
   Our application's core intelligence is powered by an agent running on Agent Engine. This agent is designed to be stateful and personalized, relying on two critical features:
   Session Management: To maintain context within a single, multi-turn conversation.
   Memory Bank: To store and retrieve long-term user preferences, history, and information across multiple sessions.
   Both of these features are fundamentally dependent on receiving a stable and unique User ID for each invocation. In our previous deployment on Cloud Run, a standard authentication flow successfully provided this User ID, allowing the agent to function as intended.
2. The Core Issue
   We are now integrating our agent with the native Agent Space interface. This new invocation path does not include a user authentication flow or pass any persistent user identifier to our backend agent on Agent Engine.
   As a result, every request from Agent Space is anonymous and isolated. Our agent has no mechanism to identify the user, link consecutive requests into a session, or access that user's specific data in the Memory Bank.
3. Impact
   This lack of user identification has a critical impact on our application's functionality and user experience:
   Loss of Intelligence: The agent becomes stateless and "amnesiac." It cannot recall previous turns in the conversation, rendering complex, multi-step tasks impossible.
   No Personalization: The Memory Bank is rendered unusable. The agent cannot access saved user preferences, history, or custom instructions, creating a generic and unintelligent experience for the user.
   Degraded User Experience: Users lose the primary benefit of a sophisticated agent—its ability to learn and adapt to them over time. This severely diminishes the value proposition of our application.
4. The Central Question / Challenge
   How can we establish a persistent user identity and manage conversational sessions for our agent when it is invoked through the native Agent Space interface, which currently provides no user context?

[hangfei]

Like the @adk-bot mentioned, the user_id identifies the session. The specific issue you mentioned are likely related to Agent Engine or Agentspace which neither @adk-bot or i have the knowledge. I suggest you check with AE or Agentspace team on that.

[adk-bot]

Response from ADK Answering Agent (experimental, answer may be inaccurate)

TLDR: Session management in Agentspace uses the ADK's Session and SessionService objects. The user_id is a required parameter when you create or retrieve a session. You can determine if a chat is new by trying to retrieve a session with a specific ID; if it doesn't exist, you create a new one.

---

Hello! Here’s a more detailed explanation of how session handling works with ADK agents, which also applies when they are deployed to Agentspace.

Session Handling and user_id

The core of session management in ADK revolves around the Session object and the SessionService.

1. The Session Object: A Session tracks the state of a single conversation. Its key identifiers are the id (often referred to as session_id), appName, and userId. [1]

2. The SessionService: This service manages the entire lifecycle of sessions. It provides methods to create, retrieve, update, and list sessions. [2, 3]

When you begin a new conversation, you must explicitly provide the user_id to the SessionService. For example:

# The user_id is a required parameter to create a session
new_session = runner.session_service.create_session(
    app_name="your-app-name",
    user_id="some-unique-user-id"
)
session_id = new_session.id

Because the user_id is a mandatory part of creating or retrieving a session, your agent will always have access to it as part of the session context. [4]

Determining a New vs. Existing Chat

Your application logic controls whether to start a new chat or continue an existing one. The common pattern is:

1. Check for an existing session: When a user interacts with your agent, first try to retrieve the session using the user_id and a session_id (if you have one). The SessionService has a get_session method for this.
2. Create a new session: If get_session does not find a session (e.g., it returns None), it means this is a new conversation for that user. You would then call create_session(...) to start a new one.

Here is a conceptual example:

from adk.services.session_service import SessionNotFoundError

def get_or_create_session(session_service, app_name, user_id, session_id=None):
    if session_id:
        try:
            # Try to resume an existing session
            return session_service.get_session(
                app_name=app_name,
                user_id=user_id,
                session_id=session_id
            )
        except SessionNotFoundError:
            # The session ID was invalid, so fall through to create a new one
            pass

    # Create a new session if no valid session_id was provided
    return session_service.create_session(
        app_name=app_name,
        user_id=user_id
    )

This ensures that you can reliably determine if you are in the context of a new or an existing chat and have access to the user_id throughout the agent's execution.

---

[1] https://google.github.io/adk-docs/sessions/session/
[2] https://google.github.io/adk-docs/sessions/
[3] https://google.github.io/adk-docs/observability/cloud-trace/
[4] https://google.github.io/adk-docs/streaming/custom-streaming/