How to get the MCP server's instructions when multi server are configured in one client?

[yp05327]

I'm using multi-server config to init my mcp client by following the doc: https://gofastmcp.com/clients/client#multi-server-example
But the MCP server (serena) is using instructions as the system prompt, so I want to get it from the client.
I found that I can get it from initialize_result.instructions when only one MCP server is set, but if multi servers are set, the value is None.