browser-testing

A browser-automation workflow for visually checking frontend and user-interface changes. It uses screenshots, page-structure inspection, and recordings of multi-step interactions as evidence.

In plain words
What is it for?
Use it after frontend changes to inspect the page, capture screenshots, check elements and attributes, test responsive layouts, and document important interactions.
Why use it?
A page can look correct in code while being broken in a real browser or at another screen size. Evidence from the running page helps confirm appearance, structure, and user flows before declaring the work correct.

Skill for Claude CodeCodex

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/roundpilot/superpowers-antigravity/browser-testing
Any agent
npx skills add roundpilot/superpowers-antigravity --skill browser-testing
Clone the repo
git clone --depth 1 https://github.com/roundpilot/superpowers-antigravity

Made for: Claude Code, Codex.

Per session 21 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 552 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 $0.00021 $0.00552
Opus 5 $0.00010 $0.00276
Sonnet 5 $0.00004 $0.00110
Haiku 4.5 $0.00002 $0.00055

Measured 3d ago against content hash 4718ee129b7f, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

browser-testing 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 3d 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.

skills/browser-testing/SKILL.md · 56 lines

How it starts

The opening of the file, as written. The whole thing — 56 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Browser Testing

Overview

Never claim UI work is correct without visual evidence. Browser automation makes verification fast and produces artifacts the user can review.

Core principle: Evidence before assertions. Screenshots and DOM inspection prove correctness; text descriptions don't.

When to use: After implementing any UI or frontend changes, before claiming the work is correct.

The Process

  1. Navigate to the page under test using browser automation
  2. Screenshot the current state — embed in walkthrough artifact
  3. Inspect DOM to verify structure matches expectations (correct elements, classes, attributes)
  4. Record a walkthrough of the key user flow (if multi-step interaction)
  5. Embed evidence in a walkthrough artifact with screenshots and recordings

Quick Reference

What to verify Tool Output
Visual appearance Screenshot ![description](/path/to/screenshot.png)
DOM structure Inspect elements Element presence, attributes, classes
User flow Recording Embedded video in artifact
Responsive layout Screenshot at viewport Multiple screenshots at different widths

Common Mistakes

Mistake Fix
Not waiting for page load before screenshot Wait for key elements to be visible
Checking only one viewport size Test at desktop (1280px) and mobile (375px) minimum
Visual-only verification (no DOM check) Always inspect DOM structure — visual can hide broken markup
Forgetting to embed evidence Every claim needs a screenshot or recording in the artifact
Saying "looks correct" without proof Take the screenshot. Embed it. Let the user judge.

Evidence classification in artifacts: Use GitHub-style alerts:

  • > [!TIP] for passing checks
  • > [!CAUTION] for failing checks
  • > [!NOTE] for observations that need human judgment

Integration

  • superpowers:verification-before-completion — browser-testing is specialized verification for UI work
  • superpowers:test-driven-development — browser tests complement unit tests, they don't replace them

Read the full file on GitHub · 56 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. 3d ago First seen · 56 lines · 21 tokens per session scan A 4718ee129b7f

Subscribe to this mod's changes

browser-testing is a skill published in the GitHub repository roundpilot/superpowers-antigravity (62 stars, last pushed 8d ago), licensed MIT. It adds 21 tokens to every session and 552 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.

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