What is steel-browser?

A skill for operating a real web browser on live sites when ordinary fetching is not enough. It supports interactive tasks such as using JavaScript-rendered pages, forms, screenshots, PDFs, login flows, and CAPTCHA or bot-protection steps.

Use it to browse dynamic websites, submit forms, capture screenshots, work with PDFs, follow login flows, and handle protected pages.

It handles websites that cannot be fully accessed by a simple request because they require a browser, interaction, or multiple navigation steps.

How ywf2016/steel-tester configures Claude Code and Cursor

Reuse

Borrowing it

Nothing to install: this file belongs to ywf2016/steel-tester. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file

curl -O https://raw.githubusercontent.com/ywf2016/steel-tester/main/.cursor/skills/steel-browser/SKILL.md

Clone the repo

git clone --depth 1 https://github.com/ywf2016/steel-tester

Made for: Claude Code, Cursor.

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/ywf2016/steel-tester/steel-browser/github.svg)](https://agentmods.dev/skills/ywf2016/steel-tester/steel-browser)

Your own site

<a href="https://agentmods.dev/skills/ywf2016/steel-tester/steel-browser"><img src="https://agentmods.dev/badge/skills/ywf2016/steel-tester/steel-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.

Your own site · 80×15

<a href="https://agentmods.dev/skills/ywf2016/steel-tester/steel-browser"><img src="https://agentmods.dev/badge/skills/ywf2016/steel-tester/steel-browser.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 133 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 729 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 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.

Model	Per session	Once invoked
Fable 5.1	$0.00133	$0.00729
Opus 5.5	$0.00053	$0.00292
Sonnet 5.5	$0.00027	$0.00146
Haiku 4.5	$0.00013	$0.00073

Measured 2mo ago against content hash 9dee3ac2724d, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

steel-browser 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.

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: 'Use this skill for live web tasks where WebFetch or curl would fail or be insufficient: JavaScript-rendered pages, forms, screenshots, PDFs, login flows, CAPTCHA/bot-protection flows, and multi-step navigat

.cursor/skills/steel-browser/SKILL.md · 85 lines

The source is not reproduced here

No licence file

Read it on GitHub

Files

What ships with it

6 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 · 85 lines · 133 tokens per session scan A 9dee3ac2724d

Subscribe to this mod's changes

steel-browser is a skill published in the GitHub repository ywf2016/steel-tester (0 stars, last pushed 3mo ago), with no licence file. It adds 133 tokens to every session and 729 once invoked, about $0.0005 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 2026-08-31.

Browser automation

steel-browser next to 6 skills from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
steel-browserywf2016/steel-tester	Skill	0	3mo ago	none	A	133	Claude Code, Cursor
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	today	MIT	A	40	Claude Code

steel-tester: Skill for Claude Code

Borrowing it

Wrote this? Show the measurements

What it costs to keep this loaded

Grade A, and why

Makes network callslowCapability

The source is not reproduced here

No licence file

What ships with it

What this file has done since we first saw it

steel-browser compared with skills from other repositories