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 0xBeycan/genesis --skill write-testsgit clone --depth 1 https://github.com/0xBeycan/genesisWrote 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/0xbeycan/genesis/write-tests)<a href="https://agentmods.dev/skills/0xbeycan/genesis/write-tests"><img src="https://agentmods.dev/badge/skills/0xbeycan/genesis/write-tests/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/0xbeycan/genesis/write-tests"><img src="https://agentmods.dev/badge/skills/0xbeycan/genesis/write-tests.svg" alt="Reviewed on agentmods" width="80" 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 | $0.00053 | $0.00378 |
| Opus 5.5 | $0.00021 | $0.00151 |
| Sonnet 5.5 | $0.00011 | $0.00076 |
| Haiku 4.5 | $0.00005 | $0.00038 |
Grade A, and why
write-tests 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 2mo 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
Write tests
When to use
Any time behavior changes — a new feature, a bug fix, a refactor that needs a
safety net. Test-first in both lanes: the failing test comes before the
code. An agent has no gut feeling for regressions; the test is its feedback
loop. See conventions.md §Testing.
Steps
- Find the behavior. What observable outcome or contract should hold? For a bug, reproduce it as a failing assertion first.
- Pick the level — unit / integration / e2e-contract, per the level guide
in
conventions.md§Testing. - Write the test against behavior, not implementation — assert outcomes
and contracts, not internals (adapter → contract test; rules in
conventions.md§Testing). - Watch it fail for the right reason (red) before writing the code.
- Implement the smallest change that makes it pass (green).
- Run the whole suite — no skipped or flaky tests left behind.
Notes
- The runner is stack-specific ({{TEST_RUNNER}} — chosen at bootstrap); its
command lives in
AGENTS.md§6 and.github/workflows/ci.yml. - Tests are part of the Definition of Done — run
review-own-diffandwrap-sessionbefore calling a change complete.
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.
- 2mo ago First seen · 36 lines · 53 tokens per session scan A d106691d1456
write-tests is a skill published in the GitHub repository 0xBeycan/genesis (12 stars, last pushed 3mo ago), licensed MIT. It adds 53 tokens to every session and 378 once invoked, about $0.0002 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 2026-08-30.
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