Borrowing it
Nothing to install: this file belongs to managedcode/dotPilot. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/managedcode/dotPilot/main/.codex/skills/dotnet-microsoft-extensions/SKILL.mdgit clone --depth 1 https://github.com/managedcode/dotPilotWrote 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/managedcode/dotpilot/dotnet-microsoft-extensions)<a href="https://agentmods.dev/skills/managedcode/dotpilot/dotnet-microsoft-extensions"><img src="https://agentmods.dev/badge/skills/managedcode/dotpilot/dotnet-microsoft-extensions/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/managedcode/dotpilot/dotnet-microsoft-extensions"><img src="https://agentmods.dev/badge/skills/managedcode/dotpilot/dotnet-microsoft-extensions.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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 | $0.00036 | $0.00404 |
| Opus 5.5 | $0.00014 | $0.00162 |
| Sonnet 5.5 | $0.00007 | $0.00081 |
| Haiku 4.5 | $0.00004 | $0.00040 |
Grade A, and why
dotnet-microsoft-extensions 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 1mo 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.
This is a copy
91% identical to dotnet-microsoft-extensions — 2 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.
What it actually says
Microsoft.Extensions for .NET
Trigger On
- wiring dependency injection, configuration, logging, or options
- introducing Generic Host patterns into non-web .NET apps
- cleaning up service registration, typed HTTP clients, or shared infrastructure code
Workflow
- Prefer the Generic Host for apps that need configuration, DI, logging, hosted services, or coordinated startup.
- Keep service registration predictable: composition at the edge, concrete implementations hidden behind interfaces only where that abstraction buys flexibility.
- Use options binding for structured configuration and validate configuration at startup when bad settings would fail later at runtime.
- Prefer
IHttpClientFactoryand typed or named clients for outbound HTTP instead of ad-hoc singleton or per-callHttpClientusage. - Use logging categories and config-driven log levels rather than scattered ad-hoc logging behavior.
- Avoid building mini-frameworks over Microsoft.Extensions unless the repo genuinely needs reusable composition primitives.
Deliver
- clean host wiring and service registration
- configuration and logging that are observable and testable
- infrastructure code that fits naturally with the .NET stack
Validate
- service lifetimes are correct
- configuration is strongly typed where it matters
- host setup remains easy to debug and reason about
References
- patterns.md - DI patterns, Configuration patterns, Options pattern, Logging patterns, HttpClientFactory patterns, Hosted Service patterns
- anti-patterns.md - Common mistakes with DI, configuration, options, logging, HttpClient, and hosted services
What ships with it
2 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.
- 1mo ago First seen · 42 lines · 36 tokens per session scan A 4986069e45d5
dotnet-microsoft-extensions is a skill published in the GitHub repository managedcode/dotPilot (25 stars, last pushed 6mo ago), licensed MIT. It adds 36 tokens to every session and 404 once invoked, about $0.0001 per session on Opus 5.5. A static security scan graded it A with 0 findings. It is 91% identical to dotnet-microsoft-extensions, differing in 2 lines, and is treated as a copy.
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