How to set default session state in ADK Web for agent testing?

[NikitaZemtsov]

I'm using Google ADK Web to test my agents. I need to set up sessions with specific initial states (e.g., user
preferences, context data, feature flags).

What are the recommended approaches to set default session state in ADK Web?

[adk-bot]

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

TLDR: You can set the default session state in ADK Web in two primary ways: by making a POST request to the session creation API endpoint with the desired state in the request body, or programmatically by using a SessionService to create a session with an initial state dictionary.

---

Hello! As a bot, I can help answer your question. Here are the recommended approaches for setting the default session state in ADK Web for agent testing:

1. Using the ADK API Server

The most direct way to create a session with a specific initial state is by using the ADK's built-in API server. This is especially useful when you are testing your agent from an external script or tool.

You can create or update a session by sending a POST request to the following endpoint:

/apps/{app_name}/users/{user_id}/sessions/{session_id}

In the body of this request, you can include a JSON object with a state key that contains your desired initial session state.

Here is an example using curl:

curl -X POST -H "Content-Type: application/json" -d '{
  "state": {
    "user_preferences": {
      "theme": "dark",
      "notifications": "enabled"
    },
    "feature_flags": {
      "new_feature_x": true
    }
  }
}' "http://127.0.0.1:8000/apps/your_app_name/users/user123/sessions/session456"

This will create a new session (session456) for the user user123 with the specified user_preferences and feature_flags already populated in the session state.

2. Programmatic Session Creation

If you are writing automated tests or integrating ADK into a larger Python application, you can create sessions with an initial state programmatically using a SessionService.

Here's an example of how you can do this with InMemorySessionService:

from adk.services import InMemorySessionService

# Initialize the session service
session_service = InMemorySessionService()

# Define your initial state
initial_state = {
    "user_preferences": {
        "language": "en-US"
    },
    "context_data": {
        "device_type": "mobile"
    }
}

# Create a new session with the initial state
session = await session_service.create_session(
    app_name="your_app_name",
    user_id="user123",
    session_id="session789",
    state=initial_state
)

Accessing the State

Once the session is created with an initial state, your agents and tools can access and modify this state through the ToolContext that is passed to them. [1]

For more information, you can refer to the official documentation on testing [2] and building agent teams [1].

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[1] https://google.github.io/adk-docs/tutorials/agent-team/
[2] https://google.github.io/adk-docs/get-started/testing/

[boyangsvl]

In addition to the bot's answer, you can also provide a state delta in the adk web UI when you send a new message.