What is browser-automation?

A tool for controlling a web browser from screenshots rather than page code or accessibility labels. It runs Chrome in the background or connects to an existing Chrome session.

Use it to open pages, read information, complete website actions, and capture screenshots during browser tasks.

It helps automate websites whose structure is difficult to access directly, while keeping browser actions separate from your own mouse and keyboard.

browser-automation — Skill for Claude Code by web-infra-dev

Install

Getting it into your agent

It runs from inside its repository, so the clone comes first — what it calls does not travel with the file alone.

Clone the repo

git clone --depth 1 https://github.com/web-infra-dev/midscene-skills

agentmods

npx agentmods add skills/web-infra-dev/midscene-skills/browser

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.

README.md

[![agentmods](https://agentmods.dev/badge/skills/web-infra-dev/midscene-skills/browser/github.svg)](https://agentmods.dev/skills/web-infra-dev/midscene-skills/browser)

Your own site

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

Per session 191 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 6,503 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. Third-party audits

NVIDIA SkillSpector pass 7 Sept 2026

How audits are shown

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	$0.00191	$0.06503
Opus 5.5	$0.00076	$0.02601
Sonnet 5.5	$0.00038	$0.01301
Haiku 4.5	$0.00019	$0.00650

Measured today against content hash 78712ff39d9f, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

browser-automation 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 today.

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.

curl -s --max-time 2 -o /dev/null -w "%{http_code}" -H "Upgrade: websocket" -H "Connection: Upgrade" -H "Sec-WebSocket-Version: 13" -H "Sec-WebSocket-Key: dGhlIHNhbXBsZSBub25jZQ==" http://127.0.0.1:9222/devtools/browser

skills/browser/SKILL.md · 434 lines

How it starts

The opening of the file, as written. The whole thing — 434 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Browser Automation

CRITICAL RULES — VIOLATIONS WILL BREAK THE WORKFLOW:

Never run midscene commands in the background. Each command must run synchronously so you can read its output (especially screenshots) before deciding the next action. Background execution breaks the screenshot-analyze-act loop.

Run only one midscene command at a time. Wait for the previous command to finish, read the screenshot, then decide the next action. Never chain multiple commands together.

Allow enough time for each command to complete. Midscene commands involve AI inference and screen interaction, which can take longer than typical shell commands. A typical command needs about 1 minute; complex act commands may need even longer.

Always report task results before finishing. After completing the automation task, you MUST proactively summarize the results to the user — including key data found, actions completed, screenshots taken, and any relevant findings. Never silently end after the last automation step; the user expects a complete response in a single interaction.

Automate web browsing using npx -y @midscene/web@1. By default, launches a headless Chrome via Puppeteer that persists across CLI calls — no session loss between commands. Also supports CDP mode and Bridge mode to connect to an existing Chrome browser.

What `act` Can Do

Inside a single act call in the browser, Midscene can click, right-click, double-click, hover, type or clear text, press keys, scroll, drag, long-press, and continue through multi-step page flows based on what is currently visible. When touch input is enabled, it can also handle swipe- or pinch-style interactions on touch-oriented pages.

When to Use

This skill has three modes. Choose based on the user's intent:

Mode Selection Guide

Mode	When to use	How it works
Puppeteer (default)	User wants to browse a URL, scrape data, test UI — no need for their own browser	Launches a new headless Chrome, isolated from user's browser
CDP mode	User says "connect to my Chrome", "control my browser", "CDP", "remote debugging", or wants to operate their existing browser. Also use when the task implicitly requires login state (e.g., "check my orders", "open my dashboard", "look at my account")	Connects to user's Chrome via DevTools Protocol. Requires remote debugging enabled (`chrome://inspect` > "Allow remote debugging"). No extension needed
Bridge mode	User explicitly mentions "bridge", "extension", or has Midscene Chrome Extension installed and prefers to use it	Connects to user's Chrome via the Midscene Chrome Extension

Read the full file on GitHub · 434 lines

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.

today Changed · +23 lines 78712ff39d9f
2mo ago First seen · 411 lines · 191 tokens per session scan A 9aa7c602a700

Subscribe to this mod's changes

browser-automation is a skill published in the GitHub repository web-infra-dev/midscene-skills (319 stars, last pushed yesterday), licensed MIT. It adds 191 tokens to every session and 6,503 once invoked, about $0.0008 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

browser-automation next to 6 skills from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
browser-automationweb-infra-dev/midscene-skills	Skill	319	yesterday	MIT	A	191	Claude Code
interactive-loginyc-software/qm	Skill	16k	today	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	today	MIT	A	56	Claude Code, Codex
southwestborski/travel-hacking-toolkit	Skill	895	today	MIT	A	40	Claude Code

browser-automation