gemini-agent-skills: Skill for Claude Code

.gemini/skills/dotnet-core-expert/SKILL.md

dotnet-core-expert is a skill for Claude Code, Gemini CLI from saeed-vayghan/gemini-agent-skills. It costs 49 tokens per session (1,244 once invoked), scanned A, original, MIT.

A specialist for cross-platform .NET and modern C# development, including minimal APIs, cloud-native applications, and microservices.

In plain words
What is it for?
Use it to build APIs and services, review .NET architecture, use modern C# features, prepare applications for containers or ahead-of-time compilation, and add OpenAPI documentation and tests.
Why use it?
It helps choose and review current .NET project structures, performance settings, deployment targets, and scalable service designs.

Skill for Claude CodeGemini CLI

Written for Claude Code and Gemini CLI: allowed-tools in frontmatter, but also installed under .gemini/.

This is saeed-vayghan/gemini-agent-skills's own configuration. It tells Claude Code and Gemini CLI how to work on gemini-agent-skills itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything gemini-agent-skills configures →

Reuse

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.

Copy the file
curl -O https://raw.githubusercontent.com/saeed-vayghan/gemini-agent-skills/master/.gemini/skills/dotnet-core-expert/SKILL.md
Clone the repo
git clone --depth 1 https://github.com/saeed-vayghan/gemini-agent-skills

Made for: Claude Code, Gemini CLI.

Wrote 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.

agentmods badge for dotnet-core-expert

README.md
[![agentmods](https://agentmods.dev/badge/skills/saeed-vayghan/gemini-agent-skills/dotnet-core-expert/github.svg)](https://agentmods.dev/skills/saeed-vayghan/gemini-agent-skills/dotnet-core-expert)
Your own site
<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.

agentmods 80×15 button for dotnet-core-expert

Your own site · 80×15
<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>
Per session 49 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,244 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00049 $0.01244
Opus 5 $0.00024 $0.00622
Sonnet 5 $0.00010 $0.00249
Haiku 4.5 $0.00005 $0.00124

Measured 11d ago against content hash 7e72876fc941, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-11, from the pricing page.

Security

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 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.

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.

.gemini/skills/dotnet-core-expert/SKILL.md · 270 lines

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:

  1. Query context manager for .NET project requirements and architecture
  2. Review application structure, performance needs, and deployment targets
  3. Analyze microservices design, cloud integration, and scalability requirements
  4. 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

Read the full file on GitHub · 270 lines

Files

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.

Changes

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.

  1. 11d ago First seen · 270 lines · 49 tokens per session scan A 7e72876fc941

Subscribe to this mod's changes

dotnet-core-expert is a skill published in the GitHub repository saeed-vayghan/gemini-agent-skills (34 stars, last pushed 7mo ago), licensed MIT. It adds 49 tokens to every session and 1,244 once invoked, about $0.0002 per session on Opus 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.