A testing workflow for Browser Control that exercises real websites and checks how navigation works. It also turns discovered fixes into small offline regression tests, which check that later changes do not break them.

It is for testing navigation on live sites, measuring performance, fixing DOM and accessibility issues, and simplifying the resulting browser automation code.

It helps reveal general browser-control problems without relying on one site's special-case workaround.

How anomalyco/browser-control configures OpenCode

Reuse

Borrowing it

Nothing to install: this file belongs to anomalyco/browser-control. 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/anomalyco/browser-control/main/.opencode/skills/gauntlet/SKILL.md

Clone the repo

git clone --depth 1 https://github.com/anomalyco/browser-control

Made for: OpenCode.

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/anomalyco/browser-control/gauntlet/github.svg)](https://agentmods.dev/skills/anomalyco/browser-control/gauntlet)

Your own site

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

Per session 69 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 1,155 The whole file, excluding the scripts and references it only reads on demand.

Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.

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	$0.00069	$0.01155
Opus 5.5	$0.00028	$0.00462
Sonnet 5.5	$0.00014	$0.00231
Haiku 4.5	$0.00007	$0.00115

Measured 22d ago against content hash b426050a19ca, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

gauntlet 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 22d 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.

.opencode/skills/gauntlet/SKILL.md · 85 lines

How it starts

The opening of the file, as written. The whole thing — 85 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Gauntlet

Run Browser Control against uncurated live websites, fix general root causes as you hit them, lock each fix in with a minimal offline regression test, and always finish with a Simplify pass so new capabilities never accumulate site-specific hacks or bloated files.

  ┌─────────────────────────────────────────────────────────────────────┐
  │                                                                     │
  ▼                                                                     │
[1. Gauntlet] ──► [2. Autoresearch] ──► [3. Simplify] ──► [4. Harvest] ─┘
 Real-site         Latency, token &      Compress code,    Promote recurring
 field tasks       round-trip profile    remove hacks      UI flows to CLIs

Workflow

1. Gauntlet — Adversarial Real-Site Field Pass

Create a dedicated session (browser-control session new "🧭 gauntlet") and pick 4–6 diverse live sites that stress different web patterns (never perform destructive/irreversible actions like placing an order):
- Portal UI libraries: https://ui.shadcn.com/docs/components/radix/select (Radix <button role="combobox">, body-portaled [role="listbox"] / [role="option"])
- Complex web apps: https://github.com/Effect-TS/effect/issues (Primer [role="menu"] / [role="menuitemradio"], filter dialogs, snapshot({ delta: true }))
- Dense SPAs & e-commerce / booking: https://resy.com, https://www.ubereats.com (top-level <header> search bars, carousels, focus-locked modals, deep card lists)
- Layout tables & prose: https://news.ycombinator.com, https://en.wikipedia.org, https://www.npmjs.com
- Web Components & Shadow DOM: https://developer.mozilla.org/en-US/docs/Web/API/ShadowRoot, https://www.reddit.com/r/typescript/
Drive each task through the public agent interface (snapshot(), ref("eN"), screenshotWithLabels(), network).
Whenever a step fails, times out, misses an interactive control, emits duplicate lines, or forces a blind waitForTimeout sleep:
- Inspect the live DOM in the session to find the general DOM, W3C ARIA, or CDP root cause.
- Never hardcode site-specific domain names or CSS class names. Express every rule in terms of standard HTML tags, ARIA roles/attributes, computed styles, or DOM structure.
- Fix the root cause in src/ (or extension/src/), add a minimal offline HTML regression check to scripts/check-snapshot.ts or test/, deploy to /Users/kit/.browser-control/current-runtime (pnpm runtime:prepare + pnpm runtime:select + browser-control relay restart), and re-verify on the live site.

Read the full file on GitHub · 85 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.

22d ago First seen · 85 lines · 69 tokens per session scan A b426050a19ca

Subscribe to this mod's changes

gauntlet is a skill published in the GitHub repository anomalyco/browser-control (467 stars, last pushed 4d ago), licensed MIT. It adds 69 tokens to every session and 1,155 once invoked, about $0.0003 per session on Opus 5.5. 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 2026-10-07.

Browser automation E2E testing Testing

browse

Drive a real browser through Aside: open a page, read it, click through a flow, take screenshots, check console errors. (gstack).

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davidondrej/skills · 68 tokens

create-verification-skill

Create a repo-local verification skill and exhaustive feature map for driving a real app through its UI, CLI, or API. Use for "create a verification skill", "make a verify skill for this repo", or "document how agents can verify this app".

get-bb/bb · 57 tokens

webapp-testing

Toolkit for interacting with and testing local web applications using Playwright. Supports verifying frontend functionality, debugging UI behavior, capturing browser screenshots, and viewing browser logs.

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browser-qa

A browser-based quality check for deployed web pages and user flows. It uses browser automation to test rendering, navigation, forms, interactions, responsive behaviour, and accessibility-related issues.

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test-electron-app

Drive the real running PostHog Electron app (live tRPC, workspace-server, real data) over CDP with agent-browser. Connect to the running app on port 9222, test desktop changes against a local Django stack, snapshot the accessibility tree, inspect network requests, and screenshot only when explicitly asked. Use when…

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browser-control: Skill for OpenCode