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 dotnet-webapigit 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/dotnet-webapi)<a href="https://agentmods.dev/skills/managedcode/dotnet-skills/dotnet-webapi"><img src="https://agentmods.dev/badge/skills/managedcode/dotnet-skills/dotnet-webapi/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/dotnet-webapi"><img src="https://agentmods.dev/badge/skills/managedcode/dotnet-skills/dotnet-webapi.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 | $0.00105 | $0.04866 |
| Opus 5.5 | $0.00042 | $0.01946 |
| Sonnet 5.5 | $0.00021 | $0.00973 |
| Haiku 4.5 | $0.00011 | $0.00487 |
Grade A, and why
dotnet-webapi 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
100% identical to dotnet-webapi — 0 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.
How it starts
The opening of the file, as written. The whole thing — 507 lines — stays where its author put it; the contents beside it link to each section on GitHub.
ASP.NET Core Web API
Produce well-structured ASP.NET Core Web API endpoints with proper HTTP semantics, OpenAPI documentation, and error handling.
When to Use
Use this skill when working on ASP.NET Core HTTP APIs, including:
- adding or modifying Web API endpoints implemented with controllers or minimal APIs;
- wiring up OpenAPI/Swagger metadata and endpoint documentation;
- defining request/response DTOs and consistent HTTP status code behavior;
- adding
.httpfiles or similar request-based API testing artifacts; - configuring centralized API error handling middleware or exception mapping.
When Not to Use
Do not use this skill for:
- general C# coding style or non-API refactoring;
- EF Core data modeling or query optimization work; use
optimizing-ef-core-queries; - frontend, Razor, or Blazor UI changes;
- gRPC services;
- SignalR hubs or real-time messaging flows.
Inputs / prerequisites
Before applying this skill, gather the project context needed to match the existing API style and wiring:
- the ASP.NET Core entry point, typically
Program.cs; - any existing controllers, especially classes inheriting
ControllerBaseor using[ApiController]; - any existing minimal API registrations such as
app.MapGet,app.MapPost,app.MapPut, orapp.MapDelete; - related DTO, model, validation, and error-handling types already used by the project;
- available build, run, and test commands so changes can be verified.
If the user asks for a new endpoint, inspect the current project structure first so the implementation follows the established conventions rather than mixing styles.
Workflow
Step 1: Determine the API style
Scan the project for existing endpoint patterns before writing any code.
- Search for classes inheriting
ControllerBaseor decorated with[ApiController]. - Search
Program.csor endpoint files forapp.MapGet,app.MapPost, etc. - If the project already uses controllers, continue with controllers.
- If the project already uses minimal APIs, continue with minimal APIs.
- If neither exists (new project), default to minimal APIs unless the user explicitly requests controllers.
What ships with it
1 file 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 · 507 lines · 105 tokens per session scan A 70e10d74aa36
dotnet-webapi is a skill published in the GitHub repository managedcode/dotnet-skills (489 stars, last pushed today), licensed MIT. It adds 105 tokens to every session and 4,866 once invoked, about $0.0004 per session on Opus 5.5. A static security scan graded it A with 0 findings. It is 100% identical to dotnet-webapi, differing in 0 lines, and is treated as a copy.
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