visual-testing

Drives the MetaMask Chrome extension via the mm CLI for visual testing in headedless Chrome. Use when asked to visually verify UI changes, capture screenshots or debug extension UI state. Trigger phrases include "verify visually", "take a screenshot", "test the flow", and "check the UI".

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Repository: MetaMask/skills
Last source activity: June 3, 2026 at 16:22
Detected SKILL.md language: English
Stars: 24
Forks: 11

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npx skills add https://github.com/MetaMask/skills --skill visual-testing

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controller-guidelines

Authoring a MetaMask controller: BaseController or not, state metadata (`persist`, `anonymous`, `usedInUi`), `this.update`, the options-bag constructor, typed messenger actions. Use when writing or reviewing a controller, or changing what it persists or exposes to the UI. To wire one in, see `controller-integration`.

2026-09-03

controller-integration

Wire a new or existing controller — whether imported from a `@metamask/*-controller` npm package or defined locally in the repo — into the MetaMask Mobile Engine or the MetaMask Extension background. Use this skill when: adding a controller to Engine or to the extension's messenger-client init, creating a controller init function or messenger, delegating actions/events between controllers, adding a controller to EngineState/Engine.context or to MESSENGER_FACTORIES and the MessengerClient union, or debugging a controller whose state never reaches Redux/the UI or resets on restart.

2026-09-03

perf-hooks-effects

Extension UI hooks and effects: when not to use `useEffect`, dependency arrays, why `JSON.stringify` deps are never the fix, cascading effects, `AbortController` cleanup. Use when an effect loops or fires every render, deps are stringified to force equality, or state lands after unmount. Rendering goes to `perf-rendering`.

2026-09-03

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name	visual-testing
description	Drives the MetaMask Chrome extension via the mm CLI for visual testing in headedless Chrome. Use when asked to visually verify UI changes, capture screenshots or debug extension UI state. Trigger phrases include "verify visually", "take a screenshot", "test the flow", and "check the UI".

visual-testing

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