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 HsuanYuLee/polaris --skill visual-regressiongit clone --depth 1 https://github.com/HsuanYuLee/polarisWrote 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/hsuanyulee/polaris/visual-regression)<a href="https://agentmods.dev/skills/hsuanyulee/polaris/visual-regression"><img src="https://agentmods.dev/badge/skills/hsuanyulee/polaris/visual-regression.svg" alt="Measured on agentmods" 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 | $0.00226 | $0.01193 |
| Opus 5 | $0.00113 | $0.00596 |
| Sonnet 5 | $0.00045 | $0.00239 |
| Haiku 4.5 | $0.00023 | $0.00119 |
Grade A, and why
visual-regression 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 8d 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 — 97 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Visual Regression
Before/after screenshot comparison guard。每次執行都抓 fresh before / after screenshots，使用 Playwright diff，分析後刪除 temporary snapshots 與 test results； 不維護 long-lived baselines。
Contract
VR 的測試單位是 domain，不是 repo。頁面由 configured URL paths 定義；不可因「頁面不在 目前 repo」而 skip。合法 skip 僅限 config 缺漏、dependency declined、clean local tree、 smart-skip 判斷無 visual impact、fixture 未建立、已知 SSR hang、環境依賴缺失。
VR 在 quality chain 中回答：「既有頁面是否仍 visually intact？」它不取代 Local CI Mirror， 也不取代 feature behavior verification。
Reference Loading
依執行情境讀取：
| Situation | Load |
|---|---|
| Any VR run | visual-regression-principles.md, visual-regression-preflight-flow.md, visual-regression-config.md, workspace-config.yaml |
| Screenshot execution | visual-regression-capture-flow.md, dependency-consent.md |
| Fixtures enabled | api-contract-guard.md, visual-regression-fixture-flow.md, vr-artifact-location.md |
| Analysis or JIRA report | visual-regression-analysis-reporting.md |
JIRA report、Slack summary，或任何 external write body 送出前，必須依
workspace-config.yaml 的 language 驗證語言。
Flow
- 解析 domain 與 company config，套用 root defaults inheritance。
- 檢查 visual regression 是否已設定；未設定則 stop，不 improvisation。
- 執行 smart skip、dependency consent、Playwright/toolchain readiness。
- 決定 SIT 或 Local comparison path；SIT 不可達時依 reference fallback。
- 透過
polaris-env.sh啟動 production-equivalent proxy 與 dev environment。 - Fixtures active 時先跑 API contract guard。
- Capture before screenshots，capture after screenshots，讓 Playwright compare。
- 分析結果、套用 first-run quality gate、必要時上傳 artifacts 並寫 JIRA wiki report。
- 無論 pass/fail/error 都 cleanup，保護 git stash、server state、temporary snapshots。
Hard Rules
- Always go through production-equivalent proxy；不可直接打 app dev port 迴避 routing。
- CSR content 必須等 deterministic selector，不使用 fixed timeout 當 readiness。
- UA-based mobile SSR 必須設定 mobile user agent，不只設 viewport。
- Fixtures active 時為 strict mode：任何 diff 都不是 data variance。
- First run after fixture setup/change 必須 human screenshot review；zero-diff 不代表截圖正確。
- Playwright tests 必須 sequential，
workers: 1。 - JIRA inline screenshot report 使用 REST API v2 wiki markup，不使用 MCP markdown comment。
What ships with it
25 files 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.
- references/api-contract-guard.md 6.4 KB
- references/dependency-consent.md 4.3 KB
- references/visual-regression-analysis-reporting.md 3.5 KB
- references/visual-regression-capture-flow.md 2.2 KB
- references/visual-regression-config.md 11 KB
- references/visual-regression-fixture-flow.md 3.9 KB
- references/visual-regression-preflight-flow.md 3.1 KB
- references/visual-regression-principles.md 3.0 KB
- references/vr-artifact-location.md 4.3 KB
- scripts/check-vr-config.sh 14 KB runs code
- scripts/contract-check.sh 12 KB runs code
- scripts/jira-upload-attachment.sh 8.2 KB runs code
- scripts/lib/main-checkout.sh 1.9 KB runs code
- scripts/lib/specs-root.sh 4.2 KB runs code
- scripts/lib/validate_specs_collection_shape_1.py 2.6 KB runs code
- scripts/polaris-env.sh 22 KB runs code
- scripts/selftests/check-vr-config-selftest.sh 12 KB runs code
- scripts/selftests/entry-points-selftest.sh 4.2 KB runs code
- scripts/sync-spec-sidebar-metadata.sh 9.9 KB runs code
- scripts/validate-specs-collection-shape.sh 4.1 KB runs code
- toolchain/package.json 627 B
- toolchain/pnpm-lock.yaml 49 KB
- toolchain/src/bin/mockoon-doctor.mjs 955 B runs code
- toolchain/src/bin/mockoon-runner.mjs 611 B runs code
- toolchain/src/bin/playwright-doctor.mjs 1.1 KB runs code
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.
- 8d ago First seen · 97 lines · 226 tokens per session scan A c92a20d6f88c
visual-regression is a skill published in the GitHub repository HsuanYuLee/polaris (5 stars, last pushed yesterday), licensed MIT. It adds 226 tokens to every session and 1,193 once invoked, about $0.0011 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.
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