Azure MCP learn=true calls time out after 180s in Copilot CLI 1.0.83-5

Bắt đầu trong đường dẫn khám phá công cụ phân cấp của Copilot CLI và tái hiện các lệnh gọi Azure đã được báo cáo với learn=true trên các phiên bản 1.0.83-5 và 1.0.80. So sánh hành vi khám phá đồng thời xác nhận rằng các lệnh gọi trực tiếp đến lệnh con vẫn thành công; hoàn tất khi cả hai probe phân cấp đều trả về schema kịp thời thay vì hết thời gian chờ sau 180 giây.

Describe the bug

Azure MCP hierarchical tool discovery calls using learn=true consistently time out after 180 seconds in Copilot CLI 1.0.83-5. The same calls complete in about 0.2 seconds under CLI 1.0.80.

Direct Azure MCP child-command calls without learn=true still succeed, which isolates the regression to hierarchical tool discovery rather than MCP startup, authentication, or general Azure connectivity.

Affected version

GitHub Copilot CLI 1.0.83-5
Windows executable file/product version: 1.0.83-5

Steps to reproduce the behavior

1. Configure the Microsoft Azure MCP server and confirm it connects.
2. Start Copilot CLI 1.0.83-5.
3. Ask the agent to make exactly one Azure Kusto MCP call with: {"intent":"Discover the Kusto command contract","learn":true}
4. Observe that the call remains pending for 180 seconds and fails with: MCP server 'azure': McpError: MCP error -32001: Request timed out
5. Repeat with Azure get_azure_bestpractices and learn=true; it fails the same way.
6. Run the same probes with CLI 1.0.80; both discovery calls succeed immediately.

Controlled A/B results:

The fresh Kusto and Best Practices A/B probes were launched simultaneously under both CLI versions with the same model, workspace, MCP configuration, and machine. All probe stderr logs were empty.

Expected behavior

learn=true should return the hierarchical tool command schema promptly, as it does under CLI 1.0.80, instead of reaching the client's 180-second timeout.

Additional context

• OS: Windows 11 Enterprise 23H2, build 22631
• Architecture: AMD64
• Shell: PowerShell 7.6.5
• Terminal: VS Code integrated terminal
• Azure MCP reached connected before each probe
• Reproduced 3/3 times on 1.0.83-5
• Control succeeded 3/3 times on 1.0.80
• No exact duplicate found in the open or closed github/copilot-cli issues