Getting it into your agent
It runs from inside its repository, so the clone comes first — what it calls does not travel with the file alone.
git clone --depth 1 https://github.com/AdamBien/airailsnpx agentmods add skills/adambien/airails/web-system-testsWrote 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/adambien/airails/web-system-tests)<a href="https://agentmods.dev/skills/adambien/airails/web-system-tests"><img src="https://agentmods.dev/badge/skills/adambien/airails/web-system-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/adambien/airails/web-system-tests"><img src="https://agentmods.dev/badge/skills/adambien/airails/web-system-tests.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 6 findings, up to medium
These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →
- medium MCP Rug Pull · line 65 npx commands without a version suffix (e.g. @1.0.0) create a rug-pull risk if the upstream server is compromised and publishes a malicious update.Fix: Pin the version: npx @scope/[email protected]
- medium MCP Rug Pull · line 116 npx commands without a version suffix (e.g. @1.0.0) create a rug-pull risk if the upstream server is compromised and publishes a malicious update.Fix: Pin the version: npx @scope/[email protected]
- medium MCP Rug Pull · line 186 npx commands without a version suffix (e.g. @1.0.0) create a rug-pull risk if the upstream server is compromised and publishes a malicious update.Fix: Pin the version: npx @scope/[email protected]
- medium MCP Rug Pull · line 190 npx commands without a version suffix (e.g. @1.0.0) create a rug-pull risk if the upstream server is compromised and publishes a malicious update.Fix: Pin the version: npx @scope/[email protected]
- medium MCP Rug Pull · line 191 npx commands without a version suffix (e.g. @1.0.0) create a rug-pull risk if the upstream server is compromised and publishes a malicious update.Fix: Pin the version: npx @scope/[email protected]
- medium MCP Rug Pull · line 192 npx commands without a version suffix (e.g. @1.0.0) create a rug-pull risk if the upstream server is compromised and publishes a malicious update.Fix: Pin the version: npx @scope/[email protected]
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 | $0.00233 | $0.02756 |
| Opus 5.5 | $0.00093 | $0.01102 |
| Sonnet 5.5 | $0.00047 | $0.00551 |
| Haiku 4.5 | $0.00023 | $0.00276 |
Grade A, and why
web-system-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 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.
How it starts
The opening of the file, as written. The whole thing — 212 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Write, run, and maintain browser-driven system tests for $ARGUMENTS. Apply all rules below strictly.
Composition
/system-testsowns the contract — black box, running system, coordinates as configuration, isolation, total verdict reporting. This skill is its web realization: layout, configuration, selector policy, test syntax, and the green oracle.- The stack skill owns the application under test —
/web-components(SPA),/web-sprinkles, or/web-static. /ears-testsowns spec-derived expectations: onetest.describeper requirement group, the literalRn.mid in the test title./bceowns where things live: one spec file per business component, named after it.
Versus the Chrome DevTools verification loop
/web-static drives the rendered page through Chrome DevTools MCP — console, accessibility
snapshot, viewport, Lighthouse, Baseline. That loop inspects the page as it is right now:
agent-driven, single-shot, leaving no artifact behind. This skill produces a committed suite
re-run by a machine on every change, in three engines, indefinitely.
Neither replaces the other. Rendering, accessibility tree, contrast, and Baseline compliance belong to the DevTools loop; user-visible behavior, and its survival across changes, belongs here. Where a project has both, green means both.
The public surface of a web UI is its accessibility tree
/system-tests permits assertions through the public surface only. For an HTTP service that surface
is the endpoint; for a web UI it is everything the user can perceive and operate — which is exactly
what the accessibility tree exposes. So the selector policy is a consequence of the contract, not a
style preference:
- Locate by role, label, text, or placeholder:
getByRole,getByLabel,getByText,getByPlaceholder. - CSS selectors, ids, class names,
nth-child, DOM shape, shadow-root piercing, and store internals are implementation. A test bound to them fails on a refactor that changed nothing a user can see — which is a false alarm, and false alarms are what kill suites.
What ships with it
1 file 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 Changed · -6 tokens per session 4e47c07faca0
- 1mo ago First seen · 212 lines · 239 tokens per session scan A 6fc2b6b6f257
web-system-tests is a skill published in the GitHub repository AdamBien/airails (58 stars, last pushed 3d ago), licensed MIT. It adds 233 tokens to every session and 2,756 once invoked, about $0.0009 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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