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 skills/okwinds/miscellany/headless-web-viewernpx skills add okwinds/miscellany --skill headless-web-viewergit clone --depth 1 https://github.com/okwinds/miscellanyWrote 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/okwinds/miscellany/headless-web-viewer)<a href="https://agentmods.dev/skills/okwinds/miscellany/headless-web-viewer"><img src="https://agentmods.dev/badge/skills/okwinds/miscellany/headless-web-viewer.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 | $0.00071 | $0.00311 |
| Opus 5 | $0.00036 | $0.00156 |
| Sonnet 5 | $0.00014 | $0.00062 |
| Haiku 4.5 | $0.00007 | $0.00031 |
Grade A, and why
headless-web-viewer scanned grade A with 1 finding 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 5d 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.
Makes network callslowCapability
Not a fault in itself. Listed so you know the mod talks to something, and to what.
description: Render and view webpages using a headless browser (Playwright) to fetch JS-rendered HTML, extract visible text, and optionally save full-page screenshots. Use when a user asks to “无头浏览器打开/查看网页”, needs the re What it actually says
Headless Web Viewer
Run
Render + save artifacts
node ./scripts/render_url_playwright.mjs '<URL>' \
--out-html /tmp/page.html \
--out-text /tmp/page.txt \
--out-screenshot /tmp/page.png
Print to stdout (pipe-friendly)
node ./scripts/render_url_playwright.mjs '<URL>' --print text
Dependencies
This skill requires Playwright in the environment where it runs.
Option A (recommended for global use, no browser download)
Install Playwright Core and use system Chrome:
npm i -D playwright-core
Run with --channel chrome.
Option B (bundled browsers)
npm i -D playwright
npx playwright install
Do not auto-install dependencies unless the user asks.
Tips
- If a page hangs on
networkidle, retry with--wait-until domcontentloaded. - If a page blocks headless Chromium, try setting
--user-agentto a realistic UA.
What ships with it
5 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.
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.
- 5d ago First seen · 53 lines · 71 tokens per session scan A 140c50e6131b
headless-web-viewer is a skill published in the GitHub repository okwinds/miscellany (50 stars, last pushed 3mo ago), licensed MIT. It adds 71 tokens to every session and 311 once invoked, about $0.0004 per session on Opus 5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
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