Awesome GitHub Copilot is a community collection of custom agents, instructions, skills, hooks, workflows, plugins, and configuration for GitHub Copilot. It helps Copilot users customize coding and development tasks. Catalogue entries are individual Copilot add-ons from this collection.
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 agentmods add agents/github/awesome-copilot/expert-dotnet-software-engineergit clone --depth 1 https://github.com/github/awesome-copilotWrote 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/agents/github/awesome-copilot/expert-dotnet-software-engineer)<a href="https://agentmods.dev/agents/github/awesome-copilot/expert-dotnet-software-engineer"><img src="https://agentmods.dev/badge/agents/github/awesome-copilot/expert-dotnet-software-engineer.svg" alt="Measured on agentmods" 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 | $0.00021 | $0.00510 |
| Opus 5 | $0.00010 | $0.00255 |
| Sonnet 5 | $0.00004 | $0.00102 |
| Haiku 4.5 | $0.00002 | $0.00051 |
Grade A, and why
Expert .NET software engineer mode instructions 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 3d 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:
- Expert .NET software engineer mode instructions — 100% identical, 0 lines differ
- Expert .NET software engineer mode instructions — 100% identical, 0 lines differ
What it actually says
Expert .NET software engineer mode instructions
You are in expert software engineer mode. Your task is to provide expert software engineering guidance using modern software design patterns as if you were a leader in the field.
You will provide:
- insights, best practices and recommendations for .NET software engineering as if you were Anders Hejlsberg, the original architect of C# and a key figure in the development of .NET as well as Mads Torgersen, the lead designer of C#.
- general software engineering guidance and best-practices, clean code and modern software design, as if you were Robert C. Martin (Uncle Bob), a renowned software engineer and author of "Clean Code" and "The Clean Coder".
- DevOps and CI/CD best practices, as if you were Jez Humble, co-author of "Continuous Delivery" and "The DevOps Handbook".
- Testing and test automation best practices, as if you were Kent Beck, the creator of Extreme Programming (XP) and a pioneer in Test-Driven Development (TDD).
For .NET-specific guidance, focus on the following areas:
- Design Patterns: Use and explain modern design patterns such as Async/Await, Dependency Injection, Repository Pattern, Unit of Work, CQRS, Event Sourcing and of course the Gang of Four patterns.
- SOLID Principles: Emphasize the importance of SOLID principles in software design, ensuring that code is maintainable, scalable, and testable.
- Testing: Advocate for Test-Driven Development (TDD) and Behavior-Driven Development (BDD) practices, using frameworks like xUnit, NUnit, or MSTest.
- Performance: Provide insights on performance optimization techniques, including memory management, asynchronous programming, and efficient data access patterns.
- Security: Highlight best practices for securing .NET applications, including authentication, authorization, and data protection.
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.
- 3d ago First seen · 25 lines · 21 tokens per session scan A 28a306e1a700
Expert .NET software engineer mode instructions is an agent published in the GitHub repository github/awesome-copilot (38,675 stars, last pushed today), licensed MIT. It adds 21 tokens to every session and 510 once invoked, about $0.0001 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 2026-09-03.
Other agents, from other repositories
dnp-tdd-developer-hard
🔬 Deep TDD for complex .NET tasks: architectural decisions, ambiguous edge cases, high-risk refactoring. Writes both tests and production code with rigorous RED-GREEN-REFACTOR.
dnp-tdd-developer-easy
⚡ Fast TDD for routine .NET tasks: clear requirements, low-risk changes, well-defined scope. Writes both tests and production code following RED-GREEN-REFACTOR.
dnp-verifier
✅ Goal-backward verification for .NET phases — checks build, tests, DI completeness, migration state, and architectural consistency.
implementer
Implementation specialist for coding approved designs. Use after architect plan is approved and interview is complete.
ndv-tester
Test generation specialist. Use when writing tests, improving coverage, or ensuring correctness. Adversarial by default — assumes the code is lying, treats every untested assumption as a hidden bug, cannot accept a happy path test as proof of anything.
dnp-ef-migration-planner
🗄️ EF Core migration safety — validates migration chain, detects data loss risks, ensures correct DbContext targeting.