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 commands/kensaurus/cursor-kenji/test-mutationgit clone --depth 1 https://github.com/kensaurus/cursor-kenjiWhat 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 | $0.00013 | $0.00133 |
| Opus 5 | $0.00006 | $0.00067 |
| Sonnet 5 | $0.00003 | $0.00027 |
| Haiku 4.5 | $0.00001 | $0.00013 |
Grade A, and why
test-mutation 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.
What it actually says
Mutation Testing
Run the test-mutation skill: install StrykerJS or mutmut, scope to
critical paths (never whole-repo first), triage survivors, and wire an
incremental per-PR job plus a score ratchet.
Coverage plan stays on plan-test-coverage. Writing tests stays on
test-unit. "Compiles and covers" is not "would notice a bug."
The full playbook lives in the test-mutation skill.
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 · 16 lines · 13 tokens per session scan A 048c09c2fa43
test-mutation is a command published in the GitHub repository kensaurus/cursor-kenji (9 stars, last pushed 4d ago), licensed MIT. It adds 13 tokens to every session and 133 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 commands, from other repositories
commit-msg
Cursor tooling: skills, rules, subagents.
boot
Initialize agent, verify setup, and load rules.
code-review
Confidence-based code review checklist.
prp-new
Create new Product Requirement Prompt from scratch.
clean
Repository hygiene — clean temp files, organize execution folders.
context
Dynamic context management — status, clean, log, save, read.