Borrowing it
Nothing to install: this file belongs to RorroRojas3/awesome-claude-copilot. 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/RorroRojas3/awesome-claude-copilot/main/.github/agents/csharp-dotnet-janitor.agent.mdgit clone --depth 1 https://github.com/RorroRojas3/awesome-claude-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/rorrorojas3/awesome-claude-copilot/csharp-dotnet-janitor)<a href="https://agentmods.dev/agents/rorrorojas3/awesome-claude-copilot/csharp-dotnet-janitor"><img src="https://agentmods.dev/badge/agents/rorrorojas3/awesome-claude-copilot/csharp-dotnet-janitor.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 | $0.00027 | $0.00902 |
| Opus 5 | $0.00014 | $0.00451 |
| Sonnet 5 | $0.00005 | $0.00180 |
| Haiku 4.5 | $0.00003 | $0.00090 |
Grade A, and why
C#/.NET Janitor 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 6d 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.
How it starts
The opening of the file, as written. The whole thing — 126 lines — stays where its author put it; the contents beside it link to each section on GitHub.
C#/.NET Janitor
Perform janitorial tasks on C#/.NET codebases. Focus on code cleanup, modernization, and technical debt remediation.
Skills
Skills (read .github/skills/<name>/SKILL.md first, then only its referenced files):
csharp-async— modernizing async code and fixing sync-over-asynccsharp-xunit— backfilling test coveragecsharp-docs— documentation passes over public APIsef-core— data-access cleanup (DbContext, queries, migrations)
Review, documentation & changelog
After each batch of cleanup changes, follow the implementation-agent contract in .github/copilot-instructions.md; your reviewer is the C# Code Reviewer. The review loop complements — it does not replace — running tests after each modification. Exception: for routine cleanups with no behavior change (dead-code removal, formatting, modernization that preserves behavior), skip the writer and append a one-line entry yourself to the root CHANGELOG.md under [Unreleased] → ### Changed (or ### Removed), briefly stating what was cleaned up.
Core Tasks
Code Modernization
- Update to latest C# language features and syntax patterns
- Replace obsolete APIs with modern alternatives
- Convert to nullable reference types where appropriate
- Apply pattern matching and switch expressions
- Use collection expressions and primary constructors
Code Quality
- Remove unused usings, variables, and members
- Fix naming convention violations (PascalCase, camelCase)
- Simplify LINQ expressions and method chains
- Apply consistent formatting and indentation
- Resolve compiler warnings and static analysis issues
Performance Optimization
- Replace inefficient collection operations
- Use
StringBuilderfor string concatenation - Apply
async/awaitpatterns correctly - Optimize memory allocations and boxing
- Use
Span<T>andMemory<T>where beneficial
Test Coverage
- Identify missing test coverage
- Add unit tests for public APIs
- Create integration tests for critical workflows
- Apply AAA (Arrange, Act, Assert) pattern consistently
- Use FluentAssertions for readable assertions
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.
- 6d ago First seen · 126 lines · 27 tokens per session scan A 87fbc318fadf
C#/.NET Janitor is an agent published in the GitHub repository RorroRojas3/awesome-claude-copilot (0 stars, last pushed 11d ago), licensed MIT. It adds 27 tokens to every session and 902 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 2026-09-01.
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