Ui Evidence

ui-evidence

한국어 README

AI changed the UI. Review the evidence.

ui-evidence helps you review what AI actually changed in the UI. It captures stable before/after screenshots or current UI snapshots, builds side-by-side comparisons, and generates a local review page a human can scan quickly.

I built it after AI coding tools started changing the wrong UI or quietly skipping related screens during frontend work. It became useful immediately in a real design-system rollout because missing screens and inconsistent button updates were easy to spot.

Why it exists

• AI can touch the wrong UI while fixing a small frontend task.
• AI can miss related screens during a design-system rollout.
• Chat screenshots are a poor review surface when a human needs to scan multiple screens quickly.

What it does

• captures stable UI screens with Playwright
• compares before and after images
• writes a local review/index.html
• supports main or another git ref as the before baseline
• attaches to an already running app when you do not want ui-evidence to launch the server
• resumes long runs and skips raw captures that already succeeded
• captures the current UI into a history snapshot bundle when you only need human review
• keeps each stage folder and snapshot run folder self-contained so you can zip one folder and share it
• opens generated HTML directly with file:// or Finder/Explorer without running a local server
• scaffolds repo-local bootstrap files after the skill or package is installed

The package is the local CLI. The skill is the easiest install surface for Codex, Claude Code, and other SKILL.md-based clients. The skill gets the workflow into the agent. The package provides the repo-local executable that actually runs captures.

Real output

Archive ledger mobile button refresh

This showcase captures a real mobile archive flow before and after a button design-system rollout. One run covers four related screens, builds pair comparisons, and produces a review surface a human can scan quickly.

Artifacts:

• before captures
• after captures
• pair comparisons
• overview image
• review HTML (open locally)
• manifest

Works with

• the open agent skills ecosystem through SKILL.md
• Codex, Claude Code, and other clients that support skills add
• local web apps with a stable route and wait target
• repos where before can come from the current checkout, a running URL, or another git ref

Supported project types

• single-package Next.js apps
• single-package Vite/React apps
• Storybook setups with a stable review route
• generic web apps that can be opened by URL and waited on with a stable selector
• JavaScript workspaces using pnpm, yarn, or npm workspaces where the review app lives under a declared workspace package such as apps/* or packages/*

Current limit:

• arbitrary nested apps without workspace metadata are not a discovery target yet

Install

Skill-first install

Install the skill with the ecosystem-native installer:

pnpm dlx skills add 0xBrewing/ui-evidence
pnpm dlx skills add 0xBrewing/ui-evidence -a codex
pnpm dlx skills add 0xBrewing/ui-evidence -a claude-code
pnpm dlx skills add 0xBrewing/ui-evidence -g -a codex

Interactive install lets the user choose the target agent, project or global scope, and symlink or copy mode.

Equivalent npx skills add ... commands work too.

By convention, the skill lands in:

• .agents/skills/ for Codex and other .agents clients
• .claude/skills/ for Claude Code

After the skill is installed, ask the agent to use it. On first use, the skill installs the ui-evidence package into the current repo and runs the repo bootstrap step automatically.

That bootstrap aligns with agent-native paths too. It writes repo-local skill copies to .agents/skills/ui-evidence/ for Codex and .claude/skills/ui-evidence/ for Claude Code, so skills add installs and installation.md bootstrap converge on recognized locations.

Shortest prompt after install:

Use ui-evidence to compare the checkout modal against main.

Direct CLI install

If you want the package without using skills add, install it from GitHub:

pnpm add -D github:0xBrewing/ui-evidence
pnpm exec ui-evidence install --agent both --config ./ui-evidence/config.yaml
pnpm exec ui-evidence doctor --config ./ui-evidence/config.yaml
pnpm exec ui-evidence doctor --config ./ui-evidence/config.yaml --ready

Equivalent install commands:

npm install -D github:0xBrewing/ui-evidence
yarn add -D github:0xBrewing/ui-evidence
bun add -d github:0xBrewing/ui-evidence

This direct CLI path still bootstraps the same agent-native local skill locations: .agents/skills/ui-evidence/ and .claude/skills/ui-evidence/.

For LLM setup

If you want to hand an installation playbook to an LLM directly:

Read https://raw.githubusercontent.com/0xBrewing/ui-evidence/main/docs/installation.md
and set up ui-evidence for this repository.
Prefer the installed ui-evidence skill if it is already available.
Keep the first setup minimal and ask only about unresolved route, wait target, auth, or baseline details.

If ui-evidence is already installed in the repo, this also works:

Read node_modules/ui-evidence/docs/installation.md and set up ui-evidence for this repository.

Quick start

Run one stage:

pnpm exec ui-evidence run --config ./ui-evidence/config.yaml --stage primary-flow

Compare the current branch against main:

pnpm exec ui-evidence run --config ./ui-evidence/config.yaml --stage primary-flow --before-ref main

Attach to an already running app and resume only the missing or failed raw captures:

pnpm exec ui-evidence run --config ./ui-evidence/config.yaml --stage primary-flow --after-attach http://127.0.0.1:3000 --resume

Capture the current UI only:

pnpm exec ui-evidence snapshot --config ./ui-evidence/config.yaml --scope design-system-rollout

If a stage has no before/after comparison artifacts yet, ui-evidence review --stage <stage-id> now reuses the latest snapshot current captures for that stage. If neither stage artifacts nor snapshot artifacts exist, the command fails clearly instead of generating an empty review. When that fallback happens, ui-evidence materializes the needed snapshot images into the stage bundle so ui-evidence/screenshots/<stage-id>/ stays portable on its own.

Profiles and params let you keep one config instead of spawning config.mobile-ko.yaml style variants:

pnpm exec ui-evidence snapshot --config ./ui-evidence/config.yaml --stage primary-flow --profile mobile-en
pnpm exec ui-evidence run --config ./ui-evidence/config.yaml --stage primary-flow --params locale=ko,variant=core

Open:

ui-evidence/screenshots/<stage-id>/review/index.html

You can open the generated HTML directly from disk. A local web server is not required.

Common prompts

• Use ui-evidence to compare the checkout modal against main
• Capture before and after screenshots for the login screen
• Bootstrap ui-evidence for this repo and keep the first setup minimal

Open skill bundle

This repo ships the standard pieces expected by the open skills ecosystem:

• agent-skill/ui-evidence/SKILL.md
• agent-skill/ui-evidence/agents/openai.yaml
• .claude-plugin/marketplace.json

The Claude plugin mirror is generated into plugins/ui-evidence/ from the canonical skill source during prepare, and is intentionally not committed so marketplace indexing sees only the canonical source path.

Minimal config shape

version: 1
project:
  name: my-app
  rootDir: ..
artifacts:
  rootDir: ui-evidence/screenshots
runtime:
  stateDir: ui-evidence/state
  tempDir: ui-evidence/tmp
capture:
  baseUrl: http://127.0.0.1:3000
  browser:
    headless: true
  viewports:
    - id: mobile-390
      device: iPhone 13
      viewport:
        width: 390
        height: 844
servers:
  after:
    command: pnpm dev
    baseUrl: http://127.0.0.1:3000
profiles:
  mobile-en:
    viewportIds:
      - mobile-390
    params:
      locale: en
stages:
  - id: primary-flow
    title: Primary Flow
    description: Stable UI surface for before/after review.
    defaultViewports:
      - mobile-390
    screens:
      - id: home
        label: Home
        path: /
        params:
          locale: en
          variant: core
        waitFor:
          testId: screen-home
scopes:
  - id: design-system-rollout
    title: Design System Rollout
    description: Current UI snapshot for touched and related screens.
    targets:
      - stageId: primary-flow
        screenIds:
          - home

Output

Each stage writes:

ui-evidence/screenshots/<stage-id>/
  before/
  after/
  comparison/
    pairs/
    overview/
  review/
    index.html
  notes.<lang>.md
  report.<lang>.md
  manifest.json

Durable runtime state and temporary worktrees now live under the canonical runtime layout:

ui-evidence/state/
  capture/
  shared/
  fixtures/
ui-evidence/tmp/
  runs/
  baseline/

Snapshot runs write:

ui-evidence/screenshots/snapshots/<run-id>/
  captures/
  overview/
  review/
    index.html
  notes.<lang>.md
  report.<lang>.md
  manifest.json

Repository files worth reading

• docs/installation.md
• examples/generic-web/ui-evidence/config.yaml
• agent-skill/ui-evidence/SKILL.md

Contributing

Issues and pull requests are welcome.

If you want to improve setup UX, skill metadata, or HTML review output, start with:

• README.md
• docs/installation.md
• agent-skill/ui-evidence/SKILL.md

License

MIT