.NET Skills is an AI coding plugin that provides skills and specialized guidance for professional .NET development, covering areas such as C#, Akka.NET, Aspire, Entity Framework Core, testing, and performance. .NET developers use it with coding assistants to apply production-oriented patterns while building and maintaining applications. The catalogue contains the plugin’s skills, agents, and instructions.
Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx skills add Aaronontheweb/dotnet-skills --skill opentelementry-dotnet-instrumentationgit clone --depth 1 https://github.com/Aaronontheweb/dotnet-skillsWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/aaronontheweb/dotnet-skills/opentelementry-dotnet-instrumentation)<a href="https://agentmods.dev/skills/aaronontheweb/dotnet-skills/opentelementry-dotnet-instrumentation"><img src="https://agentmods.dev/badge/skills/aaronontheweb/dotnet-skills/opentelementry-dotnet-instrumentation/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/aaronontheweb/dotnet-skills/opentelementry-dotnet-instrumentation"><img src="https://agentmods.dev/badge/skills/aaronontheweb/dotnet-skills/opentelementry-dotnet-instrumentation.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00056 | $0.06248 |
| Opus 5 | $0.00028 | $0.03124 |
| Sonnet 5 | $0.00011 | $0.01250 |
| Haiku 4.5 | $0.00006 | $0.00625 |
Grade A, and why
opentelemetry-net-instrumentation scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 12d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 515 lines — stays where its author put it; the contents beside it link to each section on GitHub.
OpenTelemetry .NET Instrumentation Skill
When to Use
- Adding OpenTelemetry instrumentation to .NET code (traces, metrics, logs)
- Creating or modifying ActivitySources, Meters, or ILogger usage
- Setting up the OpenTelemetry SDK, resources, exporters, or sampling
- Reviewing telemetry implementations for spec compliance
- Optimizing instrumentation performance
- Designing telemetry APIs that become part of the public surface
- Implementing context propagation across service boundaries
Architecture: .NET Is Different
CRITICAL: The .NET OpenTelemetry implementation is fundamentally different from other platforms. .NET provides tracing, metrics, and logging APIs in the framework itself. That means OTel does not provide a separate instrumentation API — it uses the built-in .NET APIs and acts as the collection/export layer.
The Three Built-in .NET APIs (Primary — Zero Dependencies)
| Signal | .NET Framework API | Namespace |
|---|---|---|
| Tracing | ActivitySource / Activity |
System.Diagnostics |
| Metrics | Meter / Counter<T> / Histogram<T> / etc. |
System.Diagnostics.Metrics |
| Logging | ILogger<T> |
Microsoft.Extensions.Logging |
These are the primary and only APIs library authors should use for instrumentation. They ship with the .NET runtime — no NuGet packages required.
The OTel Collection/Export Layer (Secondary — Application Root Only)
OTel NuGet packages are the collection and export layer, added only at the application composition root (not in libraries):
| Package | Purpose | When to add |
|---|---|---|
OpenTelemetry.Extensions.Hosting |
DI integration for ASP.NET Core / generic host | Application only |
OpenTelemetry.Exporter.Console |
Console exporter (dev/testing) | Application only |
OpenTelemetry.Exporter.OpenTelemetryProtocol |
OTLP exporter (production) | Application only |
OpenTelemetry.Exporter.Prometheus* |
Prometheus metrics endpoint | Application only |
OpenTelemetry.Instrumentation.AspNetCore |
Auto-instrument ASP.NET Core requests | Application only |
OpenTelemetry.Instrumentation.Http |
Auto-instrument HttpClient calls | Application only |
OpenTelemetry.Instrumentation.SqlClient |
Auto-instrument SQL calls | Application only |
What ships with it
3 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 12d ago First seen · 515 lines · 56 tokens per session scan A ee4c4d2d7583
opentelemetry-net-instrumentation is a skill published in the GitHub repository Aaronontheweb/dotnet-skills (1,152 stars, last pushed yesterday), licensed MIT. It adds 56 tokens to every session and 6,248 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
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opentelemetry
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opentelemetry-docs
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observability
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