How to suppress sub-agent output in UI for SequentialAgent?

[umairrkhn]

Is there a way to hide or suppress the output of a specific sub-agent in the UI, when it’s part of a SequentialAgent workflow? I want the sub-agent to run (for its side effects), but not display its output to the user. Thanks!

[hdvsarm]

Hey @umairrkhn did you find a workaround for this? I have tried a lot of options and nothing seems to work.

[EPastrana199]

You can use a callback before or after to solve this, you could provide more details so we can understand better.

[arryon]

@umairrkhn you can consider whether the pattern used inside AgentTool is useful for this. It will default to running the agent as a tool, with its own Runner and temporary session, and wait for the final event until releasing control back to the parent agent event loop. See https://github.com/google/adk-python/blob/main/src/google/adk/tools/agent_tool.py#L129

[sFritsch09]

@umairrkhn you can consider whether the pattern used inside AgentTool is useful for this. It will default to running the agent as a tool, with its own Runner and temporary session, and wait for the final event until releasing control back to the parent agent event loop. See https://github.com/google/adk-python/blob/main/src/google/adk/tools/agent_tool.py#L129

This works thanks, solution use SequentialAgent as AgentTools:

from google.adk.agents import SequentialAgent

event_announcement_agent = SequentialAgent(
    name="event_announcement_agent",
    sub_agents=[event_planner_agent, event_communications_agent],
    description="A workflow that first plans an event and then sends out announcements.",
)

# use SequentialAgent as AgentTool ==>

from google.adk.tools.agent_tool import AgentTool

guest_list_manager_tool = AgentTool(agent=guest_management_agent)
event_announcement_tool = AgentTool(agent=event_announcement_agent)

# ==> set as tools
root_orchestrator_agent = Agent(
    name="root_orchestrator_agent",
    model="gemini-2.5-flash",
    description="The main orchestrator that delegates tasks to specialist agents for event planning and guest management.",
    instruction="""
    You are the root orchestrator managing an ongoing conversation. Your job is to understand the full context of the user's request and delegate it to the correct specialist tool.

    - If the user wants to plan an event, find venues, or create a schedule, and then send email announcements use the `event_announcement_tool`.
    - If the user wants to add, view, or manage guests, use the `guest_list_manager_tool`.

    Do not try to answer the user's query directly. Always delegate to the appropriate tool. Do not summarize responses from the tools.

    """,
    tools=[event_announcement_tool, guest_list_manager_tool]
)

It is really not clear in the documentation on how to use SequentialAgent but I think AgentTool works much better instead of adding SequentialAgent as sub_agent:
https://google.github.io/adk-docs/agents/workflow-agents/sequential-agents