Streamable HTTP error - Session not found

[srdan-bozovic-msft]

Describe the bug

I can successfully add and start using MCP. However, after a while, MCP calls start consistently failing with an error.

Streamable HTTP error: Error POSTing to endpoint: {"error":{"code":-32001,"message":"Session not found"},"id":"","jsonrpc":"2.0"}

Exit / resume of Copilot CLI mitigates the issue but is annoying.

Affected version

GitHub Copilot CLI 0.0.406.

Steps to reproduce the behavior

No response

Expected behavior

No response

Additional context

• Windows x86_64