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 managedcode/dotnet-skills --skill aspnet-coregit clone --depth 1 https://github.com/managedcode/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/managedcode/dotnet-skills/aspnet-core)<a href="https://agentmods.dev/skills/managedcode/dotnet-skills/aspnet-core"><img src="https://agentmods.dev/badge/skills/managedcode/dotnet-skills/aspnet-core/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/dotnet-skills/aspnet-core"><img src="https://agentmods.dev/badge/skills/managedcode/dotnet-skills/aspnet-core.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 | $0.00122 | $0.01842 |
| Opus 5.5 | $0.00049 | $0.00737 |
| Sonnet 5.5 | $0.00024 | $0.00368 |
| Haiku 4.5 | $0.00012 | $0.00184 |
Grade A, and why
aspnet-core 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
2 near-identical copies found in the catalogue:
- dotnet-aspnet-core — 89% identical, 19 lines differ
- dotnet-aspnet-core — 86% identical, 21 lines differ
How it starts
The opening of the file, as written. The whole thing — 206 lines — stays where its author put it; the contents beside it link to each section on GitHub.
ASP.NET Core
Trigger On
- working on ASP.NET Core apps, services, or middleware
- changing auth, routing, configuration, hosting, or deployment behavior
- deciding between ASP.NET Core sub-stacks such as Blazor, Minimal APIs, or controller APIs
- debugging request pipeline issues
- modernizing legacy ASP.NET to ASP.NET Core
Documentation
- ASP.NET Core Overview
- ASP.NET Core Middleware
- ASP.NET Core Best Practices
- Configuration in ASP.NET Core
- Authentication and Authorization
References
- patterns.md - Detailed middleware patterns, security patterns, configuration patterns, DI patterns, error handling patterns, and logging patterns
- anti-patterns.md - Common ASP.NET Core mistakes including HttpClient misuse, async anti-patterns, configuration errors, DI issues, middleware ordering problems, and security vulnerabilities
Workflow
-
Detect the real hosting shape first:
- top-level
Program.csstructure - middleware order and registration
- auth model (Identity, JWT, OAuth, cookies)
- endpoint registrations and routing
- top-level
-
Follow the correct middleware order:
ExceptionHandler → HttpsRedirection → Static Files → Routing → CORS → Authentication → Authorization → Rate Limiting → Response Caching → Custom Middleware → Endpoints -
Use built-in patterns correctly:
- Prefer
IOptions<T>/IOptionsSnapshot<T>for configuration - Use
ILogger<T>for structured logging - Use
IHttpClientFactoryfor HTTP clients (nevernew HttpClient()) - Use
IHostedService/BackgroundServicefor background work
- Prefer
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 · 206 lines · 122 tokens per session scan A fd83447ae5c9
aspnet-core is a skill published in the GitHub repository managedcode/dotnet-skills (488 stars, last pushed yesterday), licensed MIT. It adds 122 tokens to every session and 1,842 once invoked, about $0.0005 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.
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