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 levnikolaevich/claude-code-skills --skill ln-42-acceptance-test-buildergit clone --depth 1 https://github.com/levnikolaevich/claude-code-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/levnikolaevich/claude-code-skills/ln-42-acceptance-test-builder)<a href="https://agentmods.dev/skills/levnikolaevich/claude-code-skills/ln-42-acceptance-test-builder"><img src="https://agentmods.dev/badge/skills/levnikolaevich/claude-code-skills/ln-42-acceptance-test-builder/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/levnikolaevich/claude-code-skills/ln-42-acceptance-test-builder"><img src="https://agentmods.dev/badge/skills/levnikolaevich/claude-code-skills/ln-42-acceptance-test-builder.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 | $0.00036 | $0.02438 |
| Opus 5 | $0.00018 | $0.01219 |
| Sonnet 5 | $0.00007 | $0.00488 |
| Haiku 4.5 | $0.00004 | $0.00244 |
Grade A, and why
ln-42-acceptance-test-builder 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 4d 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 — 106 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Acceptance Test Builder
Goal: Deliver the smallest trustworthy acceptance-test portfolio for stated requirements through a user- or external-system-observable boundary. Modify only approved tests and test documentation; implement justified additions, updates, merges, and deletions without repairing product code.
Execution contract: The ordered checkboxes are the Definition of Done. Track every item internally as PENDING, PROVEN with concrete evidence, CLEARED with evidence that its condition is absent, or UNPROVEN with a gap; reading, delegation, or tool failure is not proof. Reconcile items after each section. Before returning, resolve all PENDING and count only PROVEN and CLEARED; apply the skill's verdict and approval rules to every gap.
Preserve user intent, scope, and existing authorization. Continue authorized work; ask only for consequential unresolved choices or required external approval. Scale depth to material risk without silently skipping checks. Preserve dependency and safety ordering; otherwise choose the verification method appropriate to each obligation.
Tool Routing
| Need | Preferred tool | Use it when | Fallback |
|---|---|---|---|
| Workspace safety | Git status, diff, repository instructions, and branch or worktree inspection | Always before editing | Stop when user changes cannot be separated safely |
| Existing test conventions | File listing, search, manifests, runner configuration, CI, and focused reads | Selecting the project-native runner, layout, fixtures, and commands | Follow the nearest maintained test pattern |
| Behavior and wiring | Language server or host-native code intelligence | Locating observable entrypoints, registration, consumers, and state boundaries | Narrow search plus direct inspection |
| Test implementation | Native editing tools and project generators | Creating tests, fixtures, helpers, and narrowly required test documentation | Minimal project-consistent files; never hand-edit generated state |
| Observable execution | Repository-defined shell commands, browser, API client, CLI, or disposable integration environment | Proving UI, protocol, command, or durable state outcomes | Return INCOMPLETE with the exact missing check |
| External contract | Official version-matched documentation or specification | Expected behavior depends on a current external API or standard | Mark it UNVERIFIED; do not encode a guessed oracle |
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.
- 4d ago Changed · -11 lines · -8 tokens per session 0fe3c576e4d2
- 11d ago First seen · 117 lines · 44 tokens per session scan A 767d17d4a054
ln-42-acceptance-test-builder is a skill published in the GitHub repository levnikolaevich/claude-code-skills (559 stars, last pushed 5d ago), licensed MIT. It adds 36 tokens to every session and 2,438 once invoked, about $0.0002 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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