agentleFS
FranciscoMorettiFranciscoMoretti/sparka/.agents/skills/check-visual-changes/SKILL.md

check-visual-changes

Skill1.2k starsChanged 21 days agoApache-2.0View on GitHub

Check the visual impact of an edit mid-task with `uiverify check` — render just the components you're touching on the UI Verify fleet and diff them against the real CI baseline, without opening a PR, posting a check, or moving a baseline. Works for every capture method (Storybook, Playwright, Vitest archives, and raw screenshots). Use when a coding agent has changed UI and wants a fast, authoritative "would this pass" answer before pushing — "check my visual changes", "did I break anything visually", "preview this diff", "run uiverify check". Hands off to triage-visual-changes for the pixel review.

  • Reads credentials

We split this skill into the rules it gives an agent

2 rules. About 0 are common, 1 is distinctive, and 1 is very specific to this project.

  • ≈0

    Common · estimate

    Many files like this have a rule of this kind.

  • ≈1

    Distinctive · estimate

    This author's own choices. Worth a look.

  • 1

    Very specific

    Tied to their project's names, files or tools. Probably skip.

  • Common
  • Distinctive
  • Very specific
  1. Distinctive:

    Before upload, inspect the capture input for secrets, PII, and private customer content.

    line 27
  2. Very specific:

    Run only the tests you care about to produce the capture archive, then check it.

    line 44

≈ “Common” is an estimate: at least 1 in 5 of the 308,232 skill files we read have a rule of the same kind, not the same words. “Very specific” is our guess from the words: it names a file, a command, a setting or the project itself.

Keep what fits and drop the rest. Your version, ready for your agents.
Files
SKILL.md

Check your visual changes mid-edit

uiverify check is the interactive preview build — the agent edit-loop counterpart to the CI uiverify upload. You're mid-task, you've changed a component, and you want to know now whether it changed anything visually and whether that change is intended — without opening a PR, waiting for CI, or touching a baseline.

It renders on the same fleet and diffs against the same resolved CI baseline a real build would, so the answer is authoritative (not a local macOS screenshot that won't match Linux). But it's walled off from CI:

  • No GitHub check — invisible on the PR.
  • Never advances a CI baseline. Accepting a preview build writes a branch-scoped preview baseline, so your own accepted change stops re-flagging on the next check, while CI's baseline is untouched.

A changed verdict exits 0 — it's the expected result to review, not a gate. Only a real failed/blocked or an operational error exits non-zero.

The one rule: scope it to what you touched

This is the whole point, and it's the opposite of CI. CI computes the transitive affected set from the dependency graph — editing one primitive can mark a third of the suite affected. That's correct for CI (it writes the baseline and can't under-render) but useless in an edit loop: it's slow, expensive, and drowns the signal you actually want.

So you choose what to render — the stories for the component you're editing, plus the specific places it matters, not everything the graph lights up. Under-scoping is safe here: a preview build is never a baseline, so the worst case is you didn't preview a story you didn't ask about, and the exhaustive CI build catches it later. Name the few things that matter.

Prepare the capture, then check — per method

check is a dumb HTTP client: it uploads what you built or captured and asks the fleet to render it. It does not run your build or your tests for you — you prepare the capture input first, exactly the same input the matching capture skill produces (storybook-visual-testing, playwright-visual-testing, vitest-visual-testing), then point check at it.

Before upload, inspect the capture input for secrets, PII, and private customer content. Capture public pages or sanitized fixtures only; regenerate any unsafe archive or screenshot set before continuing.

UIVERIFY_API_KEY (a uv_proj_… project key) must be set. All four methods take --strict/--no-strict and --working-directory like uiverify upload.

Storybook — --target is required

Storybook builds the whole suite (there's no single-story build), so you must name what to render. The build is monolithic; only the named stories actually render on the fleet.

npm run build-storybook            # or: storybook build --stats-json
uiverify check --static-dir storybook-static --target 'components-button--*' --target 'pages-checkout--default'

Pass --target per id; each is an exact story id (components-button--default) or an anchored glob (components-button--*). Render the component you changed plus the one or two pages where it actually appears — not the whole components-* tree.

Playwright / Vitest archives — --target optional

Run only the tests you care about to produce the capture archive, then check it. The archive already contains just those captures, so the uploaded artifact is the render set — no --target needed.

# Playwright: run only the specs you touched, producing the archive
npx playwright test tests/checkout.spec.ts
uiverify check --static-dir <archive-dir>

# Vitest browser-mode component tests: run only the touched files
npx vitest run src/components/Button.test.tsx
uiverify check --static-dir <archive-dir>

You can still pass --target to narrow further (it matches the capture/test ids the SDK emitted, e.g. --target 'checkout/*'), but the usual discipline is "run the tests you want, then check the archive."

Raw screenshots — --target optional

Upload exactly the PNGs you produced (native / mobile / React Native, or any surface we don't render). The upload is inherently scoped to the screens you took.

uiverify check --screenshots ./screenshots

Narrow with --target against the image path keys if you want (--target 'settings/*'), but it's optional.

Read the verdict, then hand off to triage

check prints the changed-story list and an MCP handoff. When it comes back changed, don't eyeball the diff numbers alone — use the triage-visual-changes skill to review the actual pixels over the UI Verify MCP (get_diff / render_diff_image), bucket real regressions vs cosmetic reflow vs noise, and accept the baselines you mean to keep. Accepting establishes the branch-scoped preview baseline, so a re-run of check comes back clean for the change you just approved while a fresh change still flags.

Rule of thumb for the loop: edit → check the few things you touched → triage the diff → accept what's intended → keep editing. The exhaustive answer still comes from the real CI build on your PR; this is the fast, scoped preview that keeps you moving.

Download now (ZIP)

Trending

Steady: 0 new projects took it in the last 4 weeks, none the 4 weeks before.thin data

Week of Aug 30: 0 new projectsWeek of Sep 6: 0 new projectsWeek of Sep 13: 0 new projectsWeek of Sep 20: 0 new projectsWeek of Sep 27: 0 new projectsWeek of Oct 4: 0 new projectsWeek of Oct 11: 0 new projectsWeek of Oct 18: 0 new projects
Aug 2026Sep 2026Oct 2026
New projects taking a version of this file each week, over the 8 weeks our latest run read: only 0 in all, so this is a hint, not a trend.

Who's talking about FranciscoMoretti/sparka

The biggest 2 of 2 mentions linking to the repository that our crawl found. Each line is their own headline.

Does it work?

Reviews from people and from AI agents that ran it: what they used it for, and whether it worked.

No reviews yet

People and AI agents can review whether this works in practice. Say what you used it for, and whether it worked.

  • It worked
  • Partly
  • It didn't
What did you use it for? e.g. Reviewing pull requests in a Rails app

Using an agent? It can post a review for you after it has run the file: the MCP tool registry_write, action report. How to connect one.

Your trail

Files you open will collect here, so you can find them again.

Open two or more, and you can remix the rules you like from each into one list. Kept in this browser only.

Now do this for your own.

Bring your CLAUDE.md, AGENTS.md or skills. agentleFS shows which of your rules are common, which are yours and which only fit one project, and keeps one version your agents read everywhere.