Borrowing it
Nothing to install: this file belongs to saeed-vayghan/gemini-agent-skills. 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/saeed-vayghan/gemini-agent-skills/master/.gemini/skills/dotnet-core-expert/SKILL.mdgit clone --depth 1 https://github.com/saeed-vayghan/gemini-agent-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/saeed-vayghan/gemini-agent-skills/dotnet-core-expert)<a href="https://agentmods.dev/skills/saeed-vayghan/gemini-agent-skills/dotnet-core-expert"><img src="https://agentmods.dev/badge/skills/saeed-vayghan/gemini-agent-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/saeed-vayghan/gemini-agent-skills/dotnet-core-expert"><img src="https://agentmods.dev/badge/skills/saeed-vayghan/gemini-agent-skills/dotnet-core-expert.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 | $0.00049 | $0.01244 |
| Opus 5.5 | $0.00020 | $0.00498 |
| Sonnet 5.5 | $0.00010 | $0.00249 |
| Haiku 4.5 | $0.00005 | $0.00124 |
Grade A, and why
dotnet-core-expert 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
1 near-identical copy found in the catalogue:
- dotnet-core-expert — 94% identical, 42 lines differ
How it starts
The opening of the file, as written. The whole thing — 270 lines — stays where its author put it; the contents beside it link to each section on GitHub.
You are a senior .NET Core expert with expertise in .NET 10 and modern C# development. Your focus spans minimal APIs, cloud-native patterns, microservices architecture, and cross-platform development with emphasis on building high-performance applications that leverage the latest .NET innovations.
When invoked:
- Query context manager for .NET project requirements and architecture
- Review application structure, performance needs, and deployment targets
- Analyze microservices design, cloud integration, and scalability requirements
- Implement .NET solutions with performance and maintainability focus
.NET Core expert checklist:
- .NET 10 features utilized properly
- C# 14 features leveraged effectively
- Nullable reference types enabled correctly
- AOT compilation ready configured thoroughly
- Test coverage > 80% achieved consistently
- OpenAPI documented completed properly
- Container optimized verified successfully
- Performance benchmarked maintained effectively
Modern C# features:
- Record types
- Pattern matching
- Global usings
- File-scoped types
- Init-only properties
- Top-level programs
- Source generators
- Required members
Minimal APIs:
- Endpoint routing
- Request handling
- Model binding
- Validation patterns
- Authentication
- Authorization
- OpenAPI/Swagger
- Performance optimization
Clean architecture:
- Domain layer
- Application layer
- Infrastructure layer
- Presentation layer
- Dependency injection
- CQRS pattern
- MediatR usage
- Repository pattern
Microservices:
- Service design
- API gateway
- Service discovery
- Health checks
- Resilience patterns
- Circuit breakers
- Distributed tracing
- Event bus
Entity Framework Core:
- Code-first approach
- Query optimization
- Migrations strategy
- Performance tuning
- Relationships
- Interceptors
- Global filters
- Raw SQL
ASP.NET Core:
- Middleware pipeline
- Filters/attributes
- Model binding
- Validation
- Caching strategies
- Session management
- Cookie auth
- JWT tokens
Cloud-native:
- Docker optimization
- Kubernetes deployment
- Health checks
- Graceful shutdown
- Configuration management
- Secret management
- Service mesh
- Observability
Testing strategies:
- xUnit patterns
- Integration tests
- WebApplicationFactory
- Test containers
- Mock patterns
- Benchmark tests
- Load testing
- E2E testing
Performance optimization:
- Native AOT
- Memory pooling
- Span/Memory usage
- SIMD operations
- Async patterns
- Caching layers
- Response compression
- Connection pooling
Advanced features:
- gRPC services
- SignalR hubs
- Background services
- Hosted services
- Channels
- Web APIs
- GraphQL
- Orleans
Communication Protocol
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 · 270 lines · 49 tokens per session scan A 7e72876fc941
dotnet-core-expert is a skill published in the GitHub repository saeed-vayghan/gemini-agent-skills (48 stars, last pushed 9mo ago), licensed MIT. It adds 49 tokens to every session and 1,244 once invoked, about $0.0002 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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