[stphnwlsh]

Summary

Traces, metrics and logs now leave the server over OTLP, and only OTLP, whenever OTEL_EXPORTER_OTLP_ENDPOINT is set. The MCP SDK's own Experimental.ModelContextProtocol spans and metrics are switched on, so a tool call reads as one trace from the HTTP request through the tool, the use case and every SQL command. Every use case gets a span and two metrics from the shared TelemetryBehaviour, every SQL command gets a span from a small EF Core interceptor (the official EF Core instrumentation is still prerelease), and Serilog sends its logs with the trace they belong to. Docker Compose swaps Seq for an OpenTelemetry Collector that forwards to the Aspire dashboard container, and Aspire appears nowhere else. Version info was already behind auth here, so the server info now just carries the real version.

• Application and Infrastructure: identical to the Minimal API change (TelemetryBehaviour, DatabaseCommandInterceptor, EF Core's built-in meter).
• Presentation: MCP SDK, ASP.NET Core, HttpClient, runtime and auth instrumentation, exemplars, health endpoints left out of traces, service.version on everything. EF Core command logs drop to Warning, since each command has a span now.
• otel-collector.yaml (OTLP receiver, memory limiter, batch, one exporter to swap for a real backend) ships in the template package.
• New telemetry skill, with a watch list for EF Core instrumentation, profiles and the events API. serilog, mediator, docker-and-compose, health-checks, optional-token-auth, configuration-and-environments and mcp-inspector updated.

Type of change

• Bug fix
• New feature
• Breaking change (the generated solution or template parameters change in a way existing users will notice)
• Refactoring or clean-up
• Documentation
• Build, pipeline or dependency update

Shared layers

• This only touches the Presentation layer of this template.
• This touches the Application or Infrastructure layers, tests, pipeline or repository setup, so it needs to be carried across all five templates.

Checklist

• dotnet build and dotnet test pass locally with no warnings.
• I added or updated tests, and line coverage stays at or above 95%.
• I updated the README or docs where behaviour changed.
• If this changes how we do something, I updated the matching skill in .agents/skills.
• I checked the template still installs and creates a working solution (see CONTRIBUTING.md).

[github-actions]

Build Pipeline

✅ Ready to merge. Every stage passed.

Stage	Result	Details
Build	🟢 Passed	Version 2026.11.04.152-pr-39 · Template package 229 KB
Test	🟢 Passed	265 passed · 0 failed · 0 skipped · Template installs, builds and passes its tests
Coverage	🟢 Passed	99.56% (914 of 918 lines) · Needs 95%
Static Analysis	🟢 Passed	No open CodeQL alerts
Dependency Review	🟢 Passed	0 vulnerable packages · 0 licence problems
Container Scan	🟢 Passed	Image starts and answers · No open Trivy alerts

_{Commit 6136dbf · Full run}