Borrowing it
Nothing to install: this file belongs to managedcode/PrompterOne. 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/PrompterOne/main/.codex/skills/dotnet-microsoft-extensions/SKILL.mdgit clone --depth 1 https://github.com/managedcode/PrompterOneWrote 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/prompterone/dotnet-microsoft-extensions)<a href="https://agentmods.dev/skills/managedcode/prompterone/dotnet-microsoft-extensions"><img src="https://agentmods.dev/badge/skills/managedcode/prompterone/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/prompterone/dotnet-microsoft-extensions"><img src="https://agentmods.dev/badge/skills/managedcode/prompterone/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 | $0.00390 |
| Opus 5.5 | $0.00014 | $0.00156 |
| Sonnet 5.5 | $0.00007 | $0.00078 |
| Haiku 4.5 | $0.00004 | $0.00039 |
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.
Copies of this mod
3 near-identical copies found in the catalogue:
- microsoft-extensions — 94% identical, 2 lines differ
- dotnet-microsoft-extensions — 91% identical, 2 lines differ
- dotnet-microsoft-extensions — 91% identical, 2 lines differ
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
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.
- 1mo ago First seen · 40 lines · 36 tokens per session scan A a18f8b53ae2e
dotnet-microsoft-extensions is a skill published in the GitHub repository managedcode/PrompterOne (45 stars, last pushed 5mo ago), licensed MIT. It adds 36 tokens to every session and 390 once invoked, about $0.0001 per session on Opus 5.5. 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.
Other skills, from other repositories
mapsui
Use when embedding interactive 2D maps in .NET desktop (WPF/WinUI/WinForms) or mobile (MAUI/Avalonia/Blazor) apps with Mapsui 5.1.0 (net8.0/net9.0) — Mapsui.Wpf/Mapsui.Maui packages, Map and Layers, OpenStreetMap.CreateTileLayer, Shapefile/GeoJSON via Mapsui.Nts, SphericalMercator.FromLonLat, or fixing a blank…
signs-of-ai
Detect and remove the tells of AI-generated writing in BOTH English and Spanish, and read back the evidence honestly. Use when the user asks to "de-AI" / "humanize" / "un-slop" a draft, to examine whether text carries the tells (delve, tapestry, "it's not just X, it's Y", "here's the thing", em-dash overuse, an…
vela
Compiler-exact code search over a SCIP index - find where a symbol is defined, every reference to it, who calls it, and what a change would break. Indexes .NET itself: C#, VB, Razor Pages, MVC views and Blazor components, with every Razor reference resolved by the compiler into a saved index, where grep sees only…
qa-tester
Verifies programmer deliveries when a ticket reaches Review. Actually runs the application/tests/endpoints to confirm the change works, sets up missing test tooling when needed, and blocks the ticket if execution is impossible. Posts a PASS/FAIL/BLOCKED report; on FAIL, returns the ticket to Todo.
documentalist
Keeps project documentation in sync with the code. Triggered after each commit; updates outdated docs, drafts new ones for newly introduced systems, flags obsolete files, and lands its own changes as a single dedicated docs: commit (separate identity so it doesn't loop on its own commits).
evaluator
Post-mortem ticket evaluator. Runs when a ticket reaches Done. Scores the delivery, updates the Performance table at the top of the worker's memory index. No comment posted on the ticket.