Getting it into your agent
It runs from inside its repository, so the clone comes first — what it calls does not travel with the file alone.
git clone --depth 1 https://github.com/trilwu/secskillsnpx agentmods add skills/trilwu/secskills/reversing-xamarin-mauiWrote 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/trilwu/secskills/reversing-xamarin-maui)<a href="https://agentmods.dev/skills/trilwu/secskills/reversing-xamarin-maui"><img src="https://agentmods.dev/badge/skills/trilwu/secskills/reversing-xamarin-maui/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/trilwu/secskills/reversing-xamarin-maui"><img src="https://agentmods.dev/badge/skills/trilwu/secskills/reversing-xamarin-maui.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- 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 | $0.00095 | $0.01915 |
| Opus 5 | $0.00048 | $0.00958 |
| Sonnet 5 | $0.00019 | $0.00383 |
| Haiku 4.5 | $0.00010 | $0.00192 |
Grade A, and why
reversing-xamarin-maui 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 13d 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 — 169 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Reversing Xamarin and .NET MAUI Apps
Xamarin apps hide a complete .NET application inside an Android package. Once you extract and decompress the assemblies you get near-source-quality C#, which makes this one of the highest-return reversing jobs — but only if you get past the container format, which changed twice and defeats naive unzipping.
When to Use
- The APK contains
lib/*/libmonodroid.so,libmonosgen-2.0.so, orlibxamarin-app.so - The APK contains
assemblies/assemblies.bloborassemblies/*.dll jadxshows onlymono.MonoPackageManagerand Xamarin bootstrap classes- An IPA contains
.dllfiles or aFrameworks/Mono*layout - The target is described as Xamarin, Xamarin.Forms, or .NET MAUI
When NOT to Use
- Unity (
global-metadata.dat,libil2cpp.so) — usereversing-unity-il2cpp; Unity is also .NET but uses a completely different packaging - Flutter or React Native — use
reversing-flutter-appsorreversing-react-native-apps - TLS interception problems — use
bypassing-mobile-pinning - The wider assessment — use
testing-mobile-applications
Identify the Packaging Generation
Three formats shipped over the product's life, and the extraction differs.
unzip -l target.apk | rg 'assemblies|libmonodroid|libxamarin|libmonosgen'
| What you see | Generation | Extraction |
|---|---|---|
assemblies/*.dll, readable PE headers (MZ) |
Classic, uncompressed | Unzip and decompile directly |
assemblies/*.dll starting with XALZ |
Classic, LZ4-compressed | Decompress the XALZ wrapper first |
assemblies/assemblies.blob + .manifest |
AssemblyStore | pyxamstore to unpack |
lib/*/libxamarin-app.so with no assemblies/ |
.NET 6+ / MAUI, assemblies in the ELF | Extract from the shared library |
| No managed assemblies anywhere | NativeAOT | Not .NET reversing — use analyzing-binaries |
# Which one is it? Check the first four bytes of an assembly
unzip -p target.apk 'assemblies/Mono.Android.dll' 2>/dev/null | xxd | head -1
# 4d5a... → MZ, a plain .NET PE, decompile now
# 58414c5a → "XALZ", LZ4-compressed, decompress first
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.
- 13d ago First seen · 169 lines · 95 tokens per session scan A 9ce642e3dda8
reversing-xamarin-maui is a skill published in the GitHub repository trilwu/secskills (138 stars, last pushed 8d ago), licensed MIT. It adds 95 tokens to every session and 1,915 once invoked, about $0.0005 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.
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