extensions-ui-test

name	extensions-ui-test
description	Use when testing, reviewing, or polishing Nevermind extension API UI fixtures, host-rendered extension views, or any UI-facing extension API endpoint. Trigger on requests mentioning extension fixtures, Fixtures root item, extension UI tests, dev-only UI fixtures, or visual polish of generated/extension views.

Extensions UI Test

Use this skill to dogfood Nevermind's host-rendered extension UI contract. The goal is to make every UI-facing extension API primitive feel polished, keyboard-first, and consistent with the rest of the app before AI-generated extensions depend on it.

Source of truth

• API contract: src/app/resources/nevermind-extension-api.d.ts
• Fixture rule: docs/extension-api-ui-fixtures.md
• Fixture extensions: src/app/fixtures/
• Current fixture entrypoint: search for Fixtures in the dev palette
• Renderer/model: src/app/palette/extension-view.tsx, src/app/palette/ui.tsx, src/app/palette/model.ts, src/app/palette/styles.css
• Runtime fixture loader: src/app/electron/main.ts
• General UI review skill: .agents/skills/ui-design/

Non-negotiable rule

Every extension API method that renders host-owned UI must have a dev-only fixture under src/app/fixtures/. If a UI API changes, update the fixture in the same change. A UI API is not done until its fixture has been manually dogfooded.

Start the app

Use the repo package-management rule:

mise exec pnpm -- pnpm dev

Run this as a background process in agent harnesses. Do not use npm, yarn, or bun directly.

The dev script starts Electron with a Chrome DevTools Protocol endpoint on port 9222 by default for automation. Override with NVM_DEV_REMOTE_DEBUGGING_PORT only if the port is busy.

Then open the palette and search Fixtures. There should be one visible fixture entrypoint named Fixtures (other normal fallback/root items may still rank below it). Opening it should show fixture commands directly, grouped by fixture extension, without an extra nesting level.

Preferred automation

Use agent-browser for Electron UI automation when available.

1. Try to load agent-browser's Electron workflow before using it:

   agent-browser skills get electron
   agent-browser skills get dogfood
   

   Some installed versions do not support skills; if it prints Unknown command: skills, fall back to agent-browser --help and continue.
2. Connect to the running Electron app:

   agent-browser --cdp 9222 snapshot -i -c
   

3. Use the preload API for deterministic checks when UI typing is flaky. Reset to root before searching; otherwise typing inside a fixture filters the child view instead of root search:

   agent-browser --cdp 9222 eval "window.nvm.hide(); window.nvm.shortcutReady()"
   agent-browser --cdp 9222 eval "window.nvm.search('fixtures').then(r => r.map(x => x.title))"
   

4. Capture accessibility snapshots and screenshots for each fixture command:

   agent-browser --cdp 9222 screenshot /tmp/nvm-fixture.png
   

5. Record issues with reproduction steps and screenshots.

If agent-browser is unavailable, still perform a manual dogfood pass and use screenshots from the OS/browser automation tools available in the environment.

Fixture traversal checklist

From the Fixtures root item, open every command in every fixture extension.

For each command, verify:

• It opens without throwing or showing raw logs.
• Search/open/action results do not trigger Electron IPC clone errors such as An object could not be cloned; extension handlers must be converted to handler IDs before crossing IPC.
• It is reachable by keyboard only.
• Enter runs the primary action.
• Cmd+K opens useful actions when actions exist.
• Back navigation returns to the fixture list predictably.
• The search input/filtering behavior is appropriate for the view.
• Empty/loading/error states are intentional and not shown on passive surfaces.
• Text, icons, accessories, and action hints are aligned and clipped correctly.
• The surface uses existing design tokens and matches Nevermind density.
• Focus, hover, selected, disabled, and destructive states are visible but not noisy.
• The UI works in default, stacked, and preview/large palette modes when applicable.

Fixture surface discovery

Do not maintain a hand-written list of every UI endpoint in this skill. Discover the current surface from the public contract and compare it with fixtures:

rg "^    [a-zA-Z]+\(|input:" src/app/resources/nevermind-extension-api.d.ts
rg "ctx\.(ui|input)\." src/app/fixtures

For each public method that returns or displays host-owned UI, verify there is a reachable fixture command or nested fixture row that exercises realistic states. If a method only returns an inline helper/action, verify it is covered inside a related fixture.

When adding a new UI method, update the public contract and add fixture coverage in the same change; update this skill only if the discovery workflow itself changes.

Visual review heuristics

Apply the ui-design skill checklist, especially:

• Compact palette density; avoid marketing-page whitespace.
• Grayscale hierarchy first; use color only as supporting signal.
• Use src/app/palette/styles.css variables, not hardcoded colors/radii.
• Native desktop feel: no pointer cursor on normal buttons, no webby focus rings on text inputs.
• One clear primary action per surface.
• Keyboard-first interactions with visible shortcut/action affordances.
• No raw JSON, stack traces, unrendered markdown, broken media, or unstyled browser defaults unless the fixture intentionally demonstrates an error state.

Common failure patterns to look for

• Fixture commands appear individually in root search instead of only through the single Fixtures entrypoint.
• Opening Fixtures adds pointless nesting before commands are visible.
• Form checkboxes inherit card/input styling and look misaligned.
• Select/multiselect controls use unpolished browser defaults or awkward heights.
• Field descriptions/errors fight the label hierarchy.
• Preview content renders as raw monospace text when markdown was expected.
• Grid tiles crop awkwardly or action hints overlap media/title.
• Action panels open empty or duplicate the primary action without value.
• Raw functions or handlers leak into search/view/action payloads, causing actions:search or view-action IPC clone failures.
• Loading states replace cached content unnecessarily.
• Camera/webview surfaces ignore action panel space or overflow the card.

Fix workflow

1. Reproduce through the Fixtures root item.
2. Capture the smallest failing fixture command and screenshot/snapshot evidence.
3. Identify whether the issue belongs in:
   • public contract: src/app/resources/nevermind-extension-api.d.ts
   • model: src/app/palette/model.ts
   • renderer: src/app/palette/extension-view.tsx or src/app/palette/ui.tsx
   • styles: src/app/palette/styles.css
   • runtime normalization/loading: src/app/electron/main.ts
   • fixture coverage: src/app/fixtures/
4. Fix the shared primitive, not the fixture data, unless the fixture is invalid.
5. Update the fixture to cover the regression.
6. Run:

   mise exec pnpm -- pnpm test
   

   This includes clone-safety checks for common extension IPC payload leaks.
7. Dogfood the affected fixture again.

Done criteria

A UI fixture polish task is done only when:

• The fixture is reachable through the single Fixtures root item.
• All affected commands were manually opened.
• Keyboard paths were verified.
• Screenshots/snapshots show the fixed states.
• mise exec pnpm -- pnpm test passes.
• Any new UI API method is documented in src/app/resources/nevermind-extension-api.d.ts and represented in src/app/fixtures/.