test-browser

test-browser is a skill for Claude Code, Codex from gvkhosla/compound-engineering-pi. It costs 14 tokens per session (2,316 once invoked), scanned A, original, MIT.

A browser-based end-to-end testing workflow for pages affected by code changes. End-to-end tests operate through the browser to check behavior as a user would experience it.

In plain words
What is it for?
Use it to open affected pages, click elements, fill forms, capture screenshots, and inspect rendered content with the agent-browser command-line tool.
Why use it?
It helps catch problems that unit or code-level tests may miss in the rendered page and its interactions. It also focuses testing on pages changed by the current branch or pull request.

Skill for Claude CodeCodex

Part of the compound-engineering plugin — 41 skills, 1 MCP server shipped together

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.

agentmods
npx agentmods add skills/gvkhosla/compound-engineering-pi/test-browser
Any agent
npx skills add gvkhosla/compound-engineering-pi --skill test-browser
Clone the repo
git clone --depth 1 https://github.com/gvkhosla/compound-engineering-pi

Made for: Claude Code, Codex.

Or install compound-engineering, the plugin that ships this one along with the rest of its 41 skills, 1 MCP server.

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 test-browser

README.md
[![agentmods](https://agentmods.dev/badge/skills/gvkhosla/compound-engineering-pi/test-browser.svg)](https://agentmods.dev/skills/gvkhosla/compound-engineering-pi/test-browser)
Your own site
<a href="https://agentmods.dev/skills/gvkhosla/compound-engineering-pi/test-browser"><img src="https://agentmods.dev/badge/skills/gvkhosla/compound-engineering-pi/test-browser.svg" alt="Measured on agentmods" height="20"></a>
Per session 14 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,316 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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.

ModelPer sessionOnce invoked
Fable 5 $0.00014 $0.02316
Opus 5 $0.00007 $0.01158
Sonnet 5 $0.00003 $0.00463
Haiku 4.5 $0.00001 $0.00232

Measured 5d ago against content hash b8849aa6a87b, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

test-browser scanned grade A with 0 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 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.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

Origin

Copies of this mod

2 near-identical copies found in the catalogue:

plugins/compound-engineering/skills/test-browser/SKILL.md · 317 lines

How it starts

The opening of the file, as written. The whole thing — 317 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Browser Test Skill

Run end-to-end browser tests on pages affected by a PR or branch changes using the agent-browser CLI.

Use agent-browser Only For Browser Automation

This workflow uses the agent-browser CLI exclusively. Do not use any alternative browser automation system, browser MCP integration, or built-in browser-control tool. If the platform offers multiple ways to control a browser, always choose agent-browser.

Use agent-browser for: opening pages, clicking elements, filling forms, taking screenshots, and scraping rendered content.

Platform-specific hints:

  • In Claude Code, do not use Chrome MCP tools (mcp__claude-in-chrome__*).
  • In Codex, do not substitute unrelated browsing tools.

Prerequisites

  • Local development server running (e.g., bin/dev, rails server, npm run dev)
  • agent-browser CLI installed (see Setup below)
  • Git repository with changes to test

Setup

command -v agent-browser >/dev/null 2>&1 && echo "Installed" || echo "NOT INSTALLED"

Install if needed:

npm install -g agent-browser
agent-browser install

See the agent-browser skill for detailed usage.

Workflow

1. Verify Installation

Before starting, verify agent-browser is available:

command -v agent-browser >/dev/null 2>&1 && echo "Ready" || (echo "Installing..." && npm install -g agent-browser && agent-browser install)

If installation fails, inform the user and stop.

2. Ask Browser Mode

Ask the user whether to run headed or headless (using the platform's question tool — e.g., AskUserQuestion in Claude Code, request_user_input in Codex, ask_user in Gemini — or present options and wait for a reply):

Do you want to watch the browser tests run?

1. Headed (watch) - Opens visible browser window so you can see tests run
2. Headless (faster) - Runs in background, faster but invisible

Store the choice and use the --headed flag when the user selects option 1.

3. Determine Test Scope

Read the full file on GitHub · 317 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.

  1. 5d ago First seen · 317 lines · 14 tokens per session scan A b8849aa6a87b

Subscribe to this mod's changes

test-browser is a skill published in the GitHub repository gvkhosla/compound-engineering-pi (51 stars, last pushed 4mo ago), licensed MIT. It adds 14 tokens to every session and 2,316 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

Related

Other skills, from other repositories