LargeToolOutputConfig handler is not used in sub agents

I am using custom agents with .NET SDK (Copilot SDK Version: 1.0.8). I am passing LargeToolOutputConfig handler as part of session creation. This works fine if any tool was called as part of orchestrator agent and generated large output. Orchestrator agent handles large out as per LargeToolOutputConfig.

But it doesn't work in case of custom agents. Custom agents are not honoring LargeToolOutputConfig. So, tool calls always write data to disk file in case of large output.

How do we pass LargeToolOutputConfig to custom agents as well?

Start by inspecting .NET SDK session creation and custom-agent setup to trace whether LargeToolOutputConfig is propagated to sub agents. Reproduce a tool call with large output through both the orchestrator and a custom agent; done means custom agents apply the configured handler instead of always writing large results to disk.

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