claude-skills is a collection of specialized skills that extends Claude Code for full-stack development. Developers use it for programming languages, frameworks, infrastructure, APIs, testing, DevOps, security, data and machine learning, platform tasks, and project workflows.
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 Jeffallan/claude-skills --skill dotnet-core-expertgit clone --depth 1 https://github.com/Jeffallan/claude-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/jeffallan/claude-skills/dotnet-core-expert)<a href="https://agentmods.dev/skills/jeffallan/claude-skills/dotnet-core-expert"><img src="https://agentmods.dev/badge/skills/jeffallan/claude-skills/dotnet-core-expert/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/jeffallan/claude-skills/dotnet-core-expert"><img src="https://agentmods.dev/badge/skills/jeffallan/claude-skills/dotnet-core-expert.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- Socket pass
- Snyk pass
- 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 | $0.00047 | $0.01157 |
| Opus 5 | $0.00023 | $0.00579 |
| Sonnet 5 | $0.00009 | $0.00231 |
| Haiku 4.5 | $0.00005 | $0.00116 |
Grade A, and why
dotnet-core-expert scanned grade A with 1 finding 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 11d 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.
Makes network callslowCapability
Not a fault in itself. Listed so you know the mod talks to something, and to what.
5. **Test** — Write comprehensive tests with xUnit and integration testing; run `dotnet test` to confirm all tests pass — if tests fail, diagnose failures, fix the implementation, and re-run before continuing; verify end Copies of this mod
2 near-identical copies found in the catalogue:
- dotnet-core-expert — 94% identical, 2 lines differ
- dotnet-core-expert — 94% identical, 2 lines differ
How it starts
The opening of the file, as written. The whole thing — 141 lines — stays where its author put it; the contents beside it link to each section on GitHub.
.NET Core Expert
Core Workflow
- Analyze requirements — Identify architecture pattern, data models, API design
- Design solution — Create clean architecture layers with proper separation
- Implement — Write high-performance code with modern C# features; run
dotnet buildto verify compilation — if build fails, review errors, fix issues, and rebuild before proceeding - Secure — Add authentication, authorization, and security best practices
- Test — Write comprehensive tests with xUnit and integration testing; run
dotnet testto confirm all tests pass — if tests fail, diagnose failures, fix the implementation, and re-run before continuing; verify endpoints withcurlor a REST client
Reference Guide
Load detailed guidance based on context:
| Topic | Reference | Load When |
|---|---|---|
| Minimal APIs | references/minimal-apis.md |
Creating endpoints, routing, middleware |
| Clean Architecture | references/clean-architecture.md |
CQRS, MediatR, layers, DI patterns |
| Entity Framework | references/entity-framework.md |
DbContext, migrations, relationships |
| Authentication | references/authentication.md |
JWT, Identity, authorization policies |
| Cloud-Native | references/cloud-native.md |
Docker, health checks, configuration |
Constraints
MUST DO
- Use .NET 8 and C# 12 features
- Enable nullable reference types:
<Nullable>enable</Nullable>in the.csproj - Use async/await for all I/O operations — e.g.,
await dbContext.Users.ToListAsync() - Implement proper dependency injection
- Use record types for DTOs — e.g.,
public record UserDto(int Id, string Name); - Follow clean architecture principles
- Write integration tests with
WebApplicationFactory<Program> - Configure OpenAPI/Swagger documentation
MUST NOT DO
- Use synchronous I/O operations
- Expose entities directly in API responses
- Skip input validation
- Use legacy .NET Framework patterns
- Mix concerns across architectural layers
- Use deprecated EF Core patterns
What ships with it
5 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.
- 11d ago First seen · 141 lines · 47 tokens per session scan A 25901e10aa73
dotnet-core-expert is a skill published in the GitHub repository Jeffallan/claude-skills (11,401 stars, last pushed 1mo ago), licensed MIT. It adds 47 tokens to every session and 1,157 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
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nauth-guide
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create-workflow-dotnet
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