Power Platform Community Forum Thread Details

Has anyone successfuly deployed a powerautomate flow that triggers and agent that uses child agents?

For my case, I can connect just fine with the main agent and I see it doing all the correct steps, however when it triggers the child agent it cancels with the error: "Sorry, something unexpected happened. We’re looking into it. Error code: SystemError..."

Yesterday I had only one successful run, but I really didn't change anything that could justify why it worked all of a sudden.

Categories:

Calling actions from Copilot Studio

Hi @margaridalimaLI

Thanks for sharing the details.

The intermittent SystemError when the child agent is triggered is a platform-side issue, not a misconfiguration on your end — the single successful run without any changes confirms that.

What's likely happening: When Power Automate triggers the main agent, it adds an extra orchestration hop when the child agent is invoked. This can hit the 100-second response time limit under certain conditions, or encounter a transient backend failure in the multi-agent orchestration layer.

Things to try while this is investigated:

Add retry logic in your flow — wrap the "Run an agent" step in a retry/do-until to handle transient failures gracefully.
Test the agent directly in Copilot Studio's test panel (without Power Automate) to confirm whether the child agent itself works reliably in isolation.
Reduce child agent complexity if it calls multiple tools/connectors — this lowers the chance of hitting the time limit.
Confirm the Asynchronous response toggle is set to Off in any "Respond to the agent" action in your flows.

To help us repro and investigate further, could you share:

How are you triggering the agent from Power Automate? (e.g., "Run an agent" action, or an event/flow trigger?)
What does the child agent do — does it call any tools, flows, or external connectors?
Roughly how long does a successful child agent run take?
How many tools/topics does each agent (parent + child) have?
What region is your environment in?