stealth-browser

stealth-browser is a skill for Claude Code from bighardperson/computer-science-skills-collection. It costs 118 tokens per session (3,086 once invoked), scanned A, original, no licence file.

A browser-automation skill for visiting websites while attempting to avoid bot detection, keep login sessions, bypass Cloudflare checks, and solve CAPTCHA tests. Cloudflare checks and CAPTCHAs are measures websites use to distinguish people from automated tools.

In plain words
What is it for?
Use it to automate browser tasks on protected websites, preserve login sessions, browse without showing normal automation signals, and handle CAPTCHA challenges.
Why use it?
It is for web automation that would otherwise be stopped by bot-detection checks or repeated logins.

Skill for Claude Code

Written for Claude Code: allowed-tools in frontmatter.

Good fit Use it to automate browser tasks on protected websites, preserve login sessions, browse without showing normal automation signals, and handle CAPTCHA challenges.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/bighardperson/computer-science-skills-collection/stealth-browser
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 bighardperson/computer-science-skills-collection --skill stealth-browser
Clone the repo
git clone --depth 1 https://github.com/bighardperson/computer-science-skills-collection

Made for: Claude Code.

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.

agentmods badge for stealth-browser

README.md
[![agentmods](https://agentmods.dev/badge/skills/bighardperson/computer-science-skills-collection/stealth-browser/github.svg)](https://agentmods.dev/skills/bighardperson/computer-science-skills-collection/stealth-browser)
Your own site
<a href="https://agentmods.dev/skills/bighardperson/computer-science-skills-collection/stealth-browser"><img src="https://agentmods.dev/badge/skills/bighardperson/computer-science-skills-collection/stealth-browser/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.

agentmods 80×15 button for stealth-browser

Your own site · 80×15
<a href="https://agentmods.dev/skills/bighardperson/computer-science-skills-collection/stealth-browser"><img src="https://agentmods.dev/badge/skills/bighardperson/computer-science-skills-collection/stealth-browser.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 118 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,086 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 2 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin unknown 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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00118 $0.03086
Opus 5 $0.00059 $0.01543
Sonnet 5 $0.00024 $0.00617
Haiku 4.5 $0.00012 $0.00309

Measured 12d ago against content hash 07d70f433389, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-11, from the pricing page.

Security

Grade A, and why

stealth-browser scanned grade A with 2 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 12d ago.

The scan reads SKILL.md. This mod also ships 8 executable files (scripts/cf_bypass.py, scripts/login_session.py, scripts/proxy_rotate.py, …), 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.

Sends data to an external URLlowData exfiltration

A POST to an outside endpoint may be telemetry or may be exfiltration; either way the mod talks to somewhere, and you should know where.

resp = requests.post("http://2captcha.com/in.php", data={

Downgraded: this mod is about security review, or the phrase is quoted, so it is likely naming the pattern rather than instructing it.

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

curl -X POST http://localhost:8191/v1 \
skills/Stealth Browser/SKILL.md · 419 lines

The source is not reproduced here

A licence we could not identify

The repository carries a LICENSE file, but it is custom or dual enough that GitHub cannot name it and neither can this catalogue. Unknown terms are not permission, so the body is not copied here. Read the licence at the source and decide for yourself.

Read it on GitHub

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.

  1. 12d ago First seen · 419 lines · 118 tokens per session scan A 07d70f433389

Subscribe to this mod's changes

stealth-browser is a skill published in the GitHub repository bighardperson/computer-science-skills-collection (48 stars, last pushed 4mo ago), with no licence file. It adds 118 tokens to every session and 3,086 once invoked, about $0.0006 per session on Opus 5. A static security scan graded it A with 2 findings (sends data to an external url, makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.