QA Testing
Systematic web app testing with three modes: full explorations, quick smoke tests, or baseline regression comparisons. Generates structured reports with health scores, screenshots, and clear reproduction steps for any issues found.
Part of gstack — a set of 8 skills designed to work together. The
npxcommand below installs the full stack. The browse and setup-browser-cookies skills require additional setup after install.
Installation
This skill is self-contained. Copy the SKILL.md below directly into your project to get started.
.claude/skills/qa/SKILL.md # Claude Code
.cursor/skills/qa/SKILL.md # CursorOr install as a personal skill (available across all your projects):
~/.claude/skills/qa/SKILL.mdYou can also install using the skills CLI:
npx skills add garrytan/gstackRequires Node.js 18+.
SKILL.md
---
name: qa
version: 1.0.0
description: |
Systematically QA test a web application. Use when asked to "qa", "QA", "test this site",
"find bugs", "dogfood", or review quality. Three modes: full (systematic exploration),
quick (30-second smoke test), regression (compare against baseline). Produces structured
report with health score, screenshots, and repro steps.
allowed-tools:
- Bash
- Read
- Write
---
# /qa: Systematic QA Testing
You are a QA engineer. Test web applications like a real user — click everything, fill every form, check every state. Produce a structured report with evidence.
## Setup
**Parse the user's request for these parameters:**
| Parameter | Default | Override example |
|-----------|---------|-----------------|
| Target URL | (required) | `https://myapp.com`, `http://localhost:3000` |
| Mode | full | `--quick`, `--regression .gstack/qa-reports/baseline.json` |
| Output dir | `.gstack/qa-reports/` | `Output to /tmp/qa` |
| Scope | Full app | `Focus on the billing page` |
| Auth | None | `Sign in to [email protected]`, `Import cookies from cookies.json` |
**Find the browse binary:**
```bash
B=$(browse/bin/find-browse 2>/dev/null || ~/.claude/skills/gstack/browse/bin/find-browse 2>/dev/null)
if [ -z "$B" ]; then
echo "ERROR: browse binary not found"
exit 1
fi
```
**Create output directories:**
```bash
REPORT_DIR=".gstack/qa-reports"
mkdir -p "$REPORT_DIR/screenshots"
```
---
## Modes
### Full (default)
Systematic exploration. Visit every reachable page. Document 5-10 well-evidenced issues. Produce health score. Takes 5-15 minutes depending on app size.
### Quick (`--quick`)
30-second smoke test. Visit homepage + top 5 navigation targets. Check: page loads? Console errors? Broken links? Produce health score. No detailed issue documentation.
### Regression (`--regression <baseline>`)
Run full mode, then load `baseline.json` from a previous run. Diff: which issues are fixed? Which are new? What's the score delta? Append regression section to report.
---
## Workflow
### Phase 1: Initialize
1. Find browse binary (see Setup above)
2. Create output directories
3. Copy report template from `qa/templates/qa-report-template.md` to output dir
4. Start timer for duration tracking
### Phase 2: Authenticate (if needed)
**If the user specified auth credentials:**
```bash
$B goto <login-url>
$B snapshot -i # find the login form
$B fill @e3 "[email protected]"
$B fill @e4 "[REDACTED]" # NEVER include real passwords in report
$B click @e5 # submit
$B snapshot -D # verify login succeeded
```
**If the user provided a cookie file:**
```bash
$B cookie-import cookies.json
$B goto <target-url>
```
**If 2FA/OTP is required:** Ask the user for the code and wait.
**If CAPTCHA blocks you:** Tell the user: "Please complete the CAPTCHA in the browser, then tell me to continue."
### Phase 3: Orient
Get a map of the application:
```bash
$B goto <target-url>
$B snapshot -i -a -o "$REPORT_DIR/screenshots/initial.png"
$B links # map navigation structure
$B console --errors # any errors on landing?
```
**Detect framework** (note in report metadata):
- `__next` in HTML or `_next/data` requests → Next.js
- `csrf-token` meta tag → Rails
- `wp-content` in URLs → WordPress
- Client-side routing with no page reloads → SPA
**For SPAs:** The `links` command may return few results because navigation is client-side. Use `snapshot -i` to find nav elements (buttons, menu items) instead.
### Phase 4: Explore
Visit pages systematically. At each page:
```bash
$B goto <page-url>
$B snapshot -i -a -o "$REPORT_DIR/screenshots/page-name.png"
$B console --errors
```
Then follow the **per-page exploration checklist** (see `qa/references/issue-taxonomy.md`):
1. **Visual scan** — Look at the annotated screenshot for layout issues
2. **Interactive elements** — Click buttons, links, controls. Do they work?
3. **Forms** — Fill and submit. Test empty, invalid, edge cases
4. **Navigation** — Check all paths in and out
5. **States** — Empty state, loading, error, overflow
6. **Console** — Any new JS errors after interactions?
7. **Responsiveness** — Check mobile viewport if relevant:
```bash
$B viewport 375x812
$B screenshot "$REPORT_DIR/screenshots/page-mobile.png"
$B viewport 1280x720
```
**Depth judgment:** Spend more time on core features (homepage, dashboard, checkout, search) and less on secondary pages (about, terms, privacy).
**Quick mode:** Only visit homepage + top 5 navigation targets from the Orient phase. Skip the per-page checklist — just check: loads? Console errors? Broken links visible?
### Phase 5: Document
Document each issue **immediately when found** — don't batch them.
**Two evidence tiers:**
**Interactive bugs** (broken flows, dead buttons, form failures):
1. Take a screenshot before the action
2. Perform the action
3. Take a screenshot showing the result
4. Use `snapshot -D` to show what changed
5. Write repro steps referencing screenshots
```bash
$B screenshot "$REPORT_DIR/screenshots/issue-001-step-1.png"
$B click @e5
$B screenshot "$REPORT_DIR/screenshots/issue-001-result.png"
$B snapshot -D
```
**Static bugs** (typos, layout issues, missing images):
1. Take a single annotated screenshot showing the problem
2. Describe what's wrong
```bash
$B snapshot -i -a -o "$REPORT_DIR/screenshots/issue-002.png"
```
**Write each issue to the report immediately** using the template format from `qa/templates/qa-report-template.md`.
### Phase 6: Wrap Up
1. **Compute health score** using the rubric below
2. **Write "Top 3 Things to Fix"** — the 3 highest-severity issues
3. **Write console health summary** — aggregate all console errors seen across pages
4. **Update severity counts** in the summary table
5. **Fill in report metadata** — date, duration, pages visited, screenshot count, framework
6. **Save baseline** — write `baseline.json` with:
```json
{
"date": "YYYY-MM-DD",
"url": "<target>",
"healthScore": N,
"issues": [{ "id": "ISSUE-001", "title": "...", "severity": "...", "category": "..." }],
"categoryScores": { "console": N, "links": N, ... }
}
```
**Regression mode:** After writing the report, load the baseline file. Compare:
- Health score delta
- Issues fixed (in baseline but not current)
- New issues (in current but not baseline)
- Append the regression section to the report
---
## Health Score Rubric
Compute each category score (0-100), then take the weighted average.
### Console (weight: 15%)
- 0 errors → 100
- 1-3 errors → 70
- 4-10 errors → 40
- 10+ errors → 10
### Links (weight: 10%)
- 0 broken → 100
- Each broken link → -15 (minimum 0)
### Per-Category Scoring (Visual, Functional, UX, Content, Performance, Accessibility)
Each category starts at 100. Deduct per finding:
- Critical issue → -25
- High issue → -15
- Medium issue → -8
- Low issue → -3
Minimum 0 per category.
### Weights
| Category | Weight |
|----------|--------|
| Console | 15% |
| Links | 10% |
| Visual | 10% |
| Functional | 20% |
| UX | 15% |
| Performance | 10% |
| Content | 5% |
| Accessibility | 15% |
### Final Score
`score = Σ (category_score × weight)`
---
## Framework-Specific Guidance
### Next.js
- Check console for hydration errors (`Hydration failed`, `Text content did not match`)
- Monitor `_next/data` requests in network — 404s indicate broken data fetching
- Test client-side navigation (click links, don't just `goto`) — catches routing issues
- Check for CLS (Cumulative Layout Shift) on pages with dynamic content
### Rails
- Check for N+1 query warnings in console (if development mode)
- Verify CSRF token presence in forms
- Test Turbo/Stimulus integration — do page transitions work smoothly?
- Check for flash messages appearing and dismissing correctly
### WordPress
- Check for plugin conflicts (JS errors from different plugins)
- Verify admin bar visibility for logged-in users
- Test REST API endpoints (`/wp-json/`)
- Check for mixed content warnings (common with WP)
### General SPA (React, Vue, Angular)
- Use `snapshot -i` for navigation — `links` command misses client-side routes
- Check for stale state (navigate away and back — does data refresh?)
- Test browser back/forward — does the app handle history correctly?
- Check for memory leaks (monitor console after extended use)
---
## Important Rules
1. **Repro is everything.** Every issue needs at least one screenshot. No exceptions.
2. **Verify before documenting.** Retry the issue once to confirm it's reproducible, not a fluke.
3. **Never include credentials.** Write `[REDACTED]` for passwords in repro steps.
4. **Write incrementally.** Append each issue to the report as you find it. Don't batch.
5. **Never read source code.** Test as a user, not a developer.
6. **Check console after every interaction.** JS errors that don't surface visually are still bugs.
7. **Test like a user.** Use realistic data. Walk through complete workflows end-to-end.
8. **Depth over breadth.** 5-10 well-documented issues with evidence > 20 vague descriptions.
9. **Never delete output files.** Screenshots and reports accumulate — that's intentional.
10. **Use `snapshot -C` for tricky UIs.** Finds clickable divs that the accessibility tree misses.
---
## Output Structure
```
.gstack/qa-reports/
├── qa-report-{domain}-{YYYY-MM-DD}.md # Structured report
├── screenshots/
│ ├── initial.png # Landing page annotated screenshot
│ ├── issue-001-step-1.png # Per-issue evidence
│ ├── issue-001-result.png
│ └── ...
└── baseline.json # For regression mode
```
Report filenames use the domain and date: `qa-report-myapp-com-2026-03-12.md`
Originally by Garry Tan / Y Combinator, adapted here as an Agent Skills compatible SKILL.md.
This skill follows the Agent Skills open standard, supported by Claude Code, Cursor, Codex, Gemini CLI, and 20+ more editors.
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