How to pass custom HTTP headers to ADK agents in Vertex Agent Engine?

[shashankram]

I tried a bunch of things and have been unable to pass custom HTTP headers to an ADK agent running in Vertex Agent Engine. Is there a documented way to allow clients calling the Vertex Agent Engine's endpoint to passthrough custom headers required by the agent?

E.g., code where I try to set the state via the state attribute while creating the session. Note that headers is stripped out and there's nothing in the invocation_context.session.state

    # Create a new session
    response = requests.post(
        f"{BASE_URL}:query",
        headers=headers(),
        data=json.dumps(
            {
                "class_method": "async_create_session",
                "input": {
                    "user_id": USER_ID,
                    "state": {
                        "x-foo": "foo",
                    },
                },
            }
        ),
    )
    response.raise_for_status()
    session = response.json()
    print(f"Created session: {session}")

    session_id = session.get("session_id") or session.get("id")

    # Stream a query to the agent
    response = requests.post(
        f"{BASE_URL}:streamQuery",
        headers=headers(),
        data=json.dumps(
            {
                "class_method": "async_stream_query",
                "input": {
                    "user_id": USER_ID,
                    "session_id": session_id,
                    "message": "What can you do?",
                },
            }
        ),
        stream=True,
    )

[klateefa]

@shashankram Thanks for reporting this. Could you share a few more details so we can look into the bug better? Specifically, what ADK version are you using, how did you deploy the agent to Vertex Agent Engine, This will help us figure out better. Also, if you’re not on the latest version of ADK, please try updating and see if the issue persists.