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 skills/claritune/mutantx/mx-detectnpx skills add Claritune/mutantx --skill mx-detectgit clone --depth 1 https://github.com/Claritune/mutantxWhat 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 | $0.00025 | $0.01043 |
| Opus 5 | $0.00013 | $0.00522 |
| Sonnet 5 | $0.00005 | $0.00209 |
| Haiku 4.5 | $0.00003 | $0.00104 |
Grade A, and why
mx-detect 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 2d 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 — 79 lines — stays where its author put it; the contents beside it link to each section on GitHub.
MutantX — Phase 1: Project Detection
You are the detection phase of a mutation testing engine. Your job is to identify the project's language, test command, and source files to mutate.
Write the detection results as JSON to .mutants/detect.json so downstream phases can consume them.
Language & Test Command Detection
If test-cmd is provided, use it directly. Otherwise, check for these indicator files in order and use the first match:
| Indicator File | Language | Default Test Command | Default Source Pattern |
|---|---|---|---|
package.json |
JavaScript/TypeScript | Read scripts.test from package.json; fall back to npx jest or npx vitest run |
src/**/*.{ts,tsx,js,jsx} minus **/*.{test,spec}.* and **/__tests__/** |
pyproject.toml or setup.py or requirements.txt |
Python | pytest |
src/**/*.py or **/*.py minus **/test_* and **/*_test.py and **/tests/** |
Cargo.toml |
Rust | cargo test |
src/**/*.rs minus test modules |
go.mod |
Go | go test ./... |
**/*.go minus *_test.go |
pom.xml |
Java (Maven) | mvn test |
src/main/**/*.java |
build.gradle |
Java (Gradle) | ./gradlew test |
src/main/**/*.java |
*.sln or *.csproj |
C# | dotnet test |
**/*.cs minus **/Tests/** and **/*.Tests/** |
mix.exs |
Elixir | mix test |
lib/**/*.ex |
Gemfile |
Ruby | bundle exec rspec or rake test |
lib/**/*.rb or app/**/*.rb |
CMakeLists.txt or Makefile (with C/C++ sources) |
C/C++ | Auto-detect: cmake --build . && ctest or make test |
src/**/*.{c,cpp,cc,cxx,h,hpp} minus test files |
If no indicator is found, ask the user for the language, test command, and source file patterns.
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.
- 2d ago First seen · 79 lines · 25 tokens per session scan A 6500cfe624c6
mx-detect is a skill published in the GitHub repository Claritune/mutantx (2 stars, last pushed 1mo ago), licensed MIT. It adds 25 tokens to every session and 1,043 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 2026-08-31.
Other skills, from other repositories
commit
Atomic git commit with conventional message. Use when the user says "commit", "save my changes", "commit this", or wants to create a git commit. Stages specific files, writes a conventional commit message with body explaining non-obvious decisions. Never uses git add -A.
systematic-debugging
4-phase root cause debugging: understand bugs before fixing.
python-run
Run and debug Python scripts in the project. Use when the user says "run python", "execute this script", "debug this py file", or wants to run/modify a .py file. Handles dependency checks, linting, execution, and error analysis.
github-code-review
Review PRs: diffs, inline comments via gh or REST.
plan
Plan mode: write markdown plan, no execution.
simplify-code
Sequential 3-lens cleanup of recent code changes.