Address async review feedback: Emit indirection, FlushSafe logging, CancellationToken propagation in McpClientPlugin

[Copilot]

Three issues flagged in review of the async anti-pattern fixes PR were left unaddressed.

Changes

• Stream.Emit – Remove unnecessary EmitAsync indirection; call onChunk(text).GetAwaiter().GetResult() directly. ConfigureAwait(false) on a synchronously-blocked call has no effect.

• AspNetCorePlugin.Stream / FlushSafe – Add optional ILogger? Logger property to the nested Stream class. CreateStream wires it to Logger.Child("stream"). FlushSafe now logs at Warn with the full exception before scheduling the retry timer, making send failures diagnosable in production.

• McpClientPlugin – Thread CancellationToken from OnBuildFunctions through the full discovery call chain:

  OnBuildFunctions(cancellationToken)
    → FetchToolsIfNeeded(cancellationToken)
      → FetchToolsFromServer(..., cancellationToken)
        → McpClientFactory.CreateAsync(..., cancellationToken: cancellationToken)
        → client.ListToolsAsync(cancellationToken: cancellationToken)
  

  Previously the token was accepted but never forwarded, so callers could not cancel in-flight tool discovery.

---

⌨️ Start Copilot coding agent tasks without leaving your editor — available in VS Code, Visual Studio, JetBrains IDEs and Eclipse.

[Copilot]

Just as a heads up, I was blocked by some firewall rules while working on your feedback. Expand below for details.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• token.botframework.com
  • Triggering command: /usr/share/dotnet/dotnet /usr/share/dotnet/dotnet exec --runtimeconfig /home/REDACTED/work/teams.net/teams.net/Tests/Microsoft.Teams.Apps.Tests/bin/Debug/net10.0/Microsoft.Teams.Apps.Tests.runtimeconfig.json --depsfile /home/REDACTED/work/teams.net/teams.net/Tests/Microsoft.Teams.Apps.Tests/bin/Debug/net10.0/Microsoft.Teams.Apps.Tests.deps.json /home/REDACTED/work/teams.net/teams.net/Tests/Microsoft.Teams.Apps.Tests/bin/Debug/net10.0/testhost.dll --port 38797 --endpoint 127.0.0.1:038797 --role client --parentprocessid 5781 --telemetryoptedin false (dns block)
  • Triggering command: /usr/share/dotnet/dotnet /usr/share/dotnet/dotnet exec --runtimeconfig /home/REDACTED/work/teams.net/teams.net/Tests/Microsoft.Teams.Apps.Tests/bin/Debug/net8.0/Microsoft.Teams.Apps.Tests.runtimeconfig.json --depsfile /home/REDACTED/work/teams.net/teams.net/Tests/Microsoft.Teams.Apps.Tests/bin/Debug/net8.0/Microsoft.Teams.Apps.Tests.deps.json /home/REDACTED/work/teams.net/teams.net/Tests/Microsoft.Teams.Apps.Tests/bin/Debug/net8.0/testhost.dll --port 44581 --endpoint 127.0.0.1:044581 --role client --parentprocessid 5782 --telemetryoptedin false (dns block)
  • Triggering command: /usr/share/dotnet/dotnet /usr/share/dotnet/dotnet exec --runtimeconfig /home/REDACTED/work/teams.net/teams.net/Tests/Microsoft.Teams.Apps.Tests/bin/Debug/net8.0/Microsoft.Teams.Apps.Tests.runtimeconfig.json --depsfile /home/REDACTED/work/teams.net/teams.net/Tests/Microsoft.Teams.Apps.Tests/bin/Debug/net8.0/Microsoft.Teams.Apps.Tests.deps.json /home/REDACTED/work/teams.net/teams.net/Tests/Microsoft.Teams.Apps.Tests/bin/Debug/net8.0/testhost.dll --port 33971 --endpoint 127.0.0.1:033971 --role client --parentprocessid 6665 --telemetryoptedin false n (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)