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 skills add managedcode/dotnet-skills --skill strykergit clone --depth 1 https://github.com/managedcode/dotnet-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/managedcode/dotnet-skills/stryker)<a href="https://agentmods.dev/skills/managedcode/dotnet-skills/stryker"><img src="https://agentmods.dev/badge/skills/managedcode/dotnet-skills/stryker/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/managedcode/dotnet-skills/stryker"><img src="https://agentmods.dev/badge/skills/managedcode/dotnet-skills/stryker.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 | $0.00112 | $0.00958 |
| Opus 5.5 | $0.00045 | $0.00383 |
| Sonnet 5.5 | $0.00022 | $0.00192 |
| Haiku 4.5 | $0.00011 | $0.00096 |
Grade A, and why
stryker 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
3 near-identical copies found in the catalogue:
- dotnet-stryker — 91% identical, 14 lines differ
- mcaf-dotnet-stryker — 89% identical, 12 lines differ
- mcaf-dotnet-stryker — 89% identical, 12 lines differ
How it starts
The opening of the file, as written. The whole thing — 107 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Stryker.NET
Trigger On
- the repo uses or wants
Stryker.NET - mutation testing is needed for high-risk code
Value
- produce a concrete project delta: code, docs, config, tests, CI, or review artifact
- reduce ambiguity through explicit planning, verification, and final validation skills
- leave reusable project context so future tasks are faster and safer
Do Not Use For
- every PR path by default in a large repo
- simple coverage collection
Inputs
- the nearest
AGENTS.md - target projects and critical paths
- time budget for mutation runs
Quick Start
- Read the nearest
AGENTS.mdand confirm scope and constraints. - Run this skill's
Workflowthrough theRalph Loopuntil outcomes are acceptable. - Return the
Required Result Formatwith concrete artifacts and verification evidence.
Workflow
- Run mutation testing on critical projects, not blindly on the whole mono-repo.
- Keep it out of the fastest PR path unless the repo explicitly accepts the runtime cost.
- Stabilize tests first; mutation testing amplifies flaky or slow suites.
Bootstrap When Missing
If Stryker.NET is not configured yet:
- Detect current state:
rg --files -g '.config/dotnet-tools.json'dotnet tool list --localdotnet tool list --global
- Prefer local tool installation for reproducible CI:
dotnet new tool-manifest(if missing)dotnet tool install stryker
- Choose a focused target scope and mutation budget before enabling CI.
- Add a dedicated mutation command in
AGENTS.mdand CI (not in the fastest PR path by default). - Run
dotnet strykeron the target project and returnstatus: configuredorstatus: improved. - If mutation testing is explicitly out of scope, return
status: not_applicable.
Deliver
- explicit mutation-test scope
- reproducible Stryker commands
Validate
- the selected scope is affordable in CI
- mutation score is interpreted with test quality, not as a vanity number
What ships with it
4 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 · 107 lines · 112 tokens per session scan A b80587ad9e28
stryker is a skill published in the GitHub repository managedcode/dotnet-skills (495 stars, last pushed yesterday), licensed MIT. It adds 112 tokens to every session and 958 once invoked, about $0.0004 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 2026-09-03.
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