What is headless-web-viewer?

A tool for opening webpages in a browser that runs without a visible window and reading the page after its scripts have loaded.

Use it to fetch rendered page text, save the resulting HTML, or capture a full-page screenshot.

It helps inspect pages whose useful content is missing from the initial HTML returned by a basic request.

headless-web-viewer — Skill for Claude Code and Codex by okwinds

Install

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.

Any agent

npx skills add okwinds/miscellany --skill headless-web-viewer

Clone the repo

git clone --depth 1 https://github.com/okwinds/miscellany

Made for: Claude Code, Codex.

Wrote 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.

README.md

[![agentmods](https://agentmods.dev/badge/skills/okwinds/miscellany/headless-web-viewer/github.svg)](https://agentmods.dev/skills/okwinds/miscellany/headless-web-viewer)

Your own site

<a href="https://agentmods.dev/skills/okwinds/miscellany/headless-web-viewer"><img src="https://agentmods.dev/badge/skills/okwinds/miscellany/headless-web-viewer/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.

Your own site · 80×15

<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="Reviewed on agentmods" width="80" height="20"></a>

Per session 71 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 311 The whole file, excluding the scripts and references it only reads on demand.

Security scan A 1 finding. A grade says what 26 rules found in the file — not that it is safe.

Origin original No closer match found in the catalogue.

Token cost

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	$0.00071	$0.00311
Opus 5.5	$0.00028	$0.00124
Sonnet 5.5	$0.00014	$0.00062
Haiku 4.5	$0.00007	$0.00031

Measured 2mo ago against content hash 140c50e6131b, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

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 2mo ago.

The scan reads SKILL.md. This mod also ships 1 executable file (scripts/render_url_playwright.mjs), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

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

agent/skills/headless-web-viewer/SKILL.md · 53 lines

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-agent to a realistic UA.

Files

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.

Changes

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 · 53 lines · 71 tokens per session scan A 140c50e6131b

Subscribe to this mod's changes

headless-web-viewer is a skill published in the GitHub repository okwinds/miscellany (50 stars, last pushed 5mo ago), licensed MIT. It adds 71 tokens to every session and 311 once invoked, about $0.0003 per session on Opus 5.5. 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.

Browser automation

headless-web-viewer next to 6 skills from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
headless-web-viewerokwinds/miscellany	Skill	50	5mo ago	MIT	A	71	Claude Code, Codex
interactive-loginyc-software/qm	Skill	16k	yesterday	MIT	A	46	Claude Code, Codex
pinchtab-mcppinchtab/pinchtab	Skill	11k	10d ago	MIT	A	52	Claude Code, Codex
azure-messaging-webpubsub-javamicrosoft/skills	Skill	3.2k	yesterday	MIT	A	43	Claude Code
cua-driverdavidondrej/skills	Skill	4.3k	3d ago	MIT	A	68	Claude Code, Codex
open-design-browsercompozy/compozy	Skill	2.8k	yesterday	MIT	A	56	Claude Code, Codex
southwestborski/travel-hacking-toolkit	Skill	895	yesterday	MIT	A	40	Claude Code

headless-web-viewer