Testability Scoring
Browser engine
Uses the qe-browser fleet skill (.claude/skills/qe-browser/) as the primary browser engine. Vibium is installed by aqe init. The legacy scripts/run-assessment.sh + Playwright path remains as a fallback when a team already has a Playwright test suite configured, but new runs should prefer:
vibium go "$TARGET_URL"
vibium wait load
vibium a11y-tree --json > /tmp/testability/tree.json
vibium eval --stdin --json <<'EOF' > /tmp/testability/signals.json
JSON.stringify({
headings: document.querySelectorAll('h1,h2,h3,h4,h5,h6').length,
testIds: document.querySelectorAll('[data-testid]').length,
forms: document.querySelectorAll('form').length,
ariaLabels: document.querySelectorAll('[aria-label]').length,
links: document.querySelectorAll('a[href]').length,
});
EOF
node .claude/skills/qe-browser/scripts/assert.js --checks '[
{"kind": "no_console_errors"},
{"kind": "no_failed_requests"}
]'
<defaulttoaction> When assessing testability:
- RUN assessment against target URL
- ANALYZE all 10 principles automatically
- GENERATE HTML report with radar chart
- PRIORITIZE improvements by impact/effort
- INTEGRATE with QX Partner for holistic view
Quick Assessment:
# Run assessment on any URL
TEST_URL='https://example.com/' npx playwright test tests/testability-scoring/testability-scoring.spec.js --project=chromium --workers=1
# Or use shell script wrapper
.claude/skills/testability-scoring/scripts/run-assessment.sh https://example.com/
The 10 Principles at a Glance:
| Principle |
Weight |
Key Question |
| Observability |
15% |
Can we see what's happening? |
| Controllability |
15% |
Can we control the application? |
| Algorithmic Simplicity |
10% |
Are behaviors predictable? |
| Algorithmic Transparency |
10% |
Can we understand what it does? |
| Algorithmic Stability |
10% |
Does behavior remain consistent? |
| Explainability |
10% |
Is the interface understandable? |
| Unbugginess |
10% |
How error-free is it? |
| Smallness |
10% |
Are components appropriately sized? |
| Decomposability |
5% |
Can we test parts in isolation? |
| Similarity |
5% |
Is the tech stack familiar? |
Grade Scale:
- A (90-100): Excellent testability
- B (80-89): Good testability
- C (70-79): Adequate testability
- D (60-69): Below average
- F (0-59): Poor testability
</defaulttoaction>
Quick Reference Card
Running Assessments
| Method |
Command |
When to Use |
| Shell Script |
./scripts/run-assessment.sh URL |
One-time assessment |
| ENV Override |
TEST_URL='URL' npx playwright test... |
CI/CD integration |
| Config File |
Update tests/testability-scoring/config.js |
Repeated runs |
Principle Details
High Weight (15% each)
| Principle |
Measures |
Indicators |
| Observability |
State visibility, logging, monitoring |
Console output, network tracking, error visibility |
| Controllability |
Input control, state manipulation |
API access, test data injection, determinism |
Medium Weight (10% each)
| Principle |
Measures |
Indicators |
| Simplicity |
Predictable behavior |
Clear I/O relationships, low complexity |
| Transparency |
Understanding what system does |
Visible processes, readable code |
| Stability |
Consistent behavior |
Change resilience, maintainability |
| Explainability |
Interface understanding |
Good docs, semantic structure, help text |
| Unbugginess |
Error-free operation |
Console errors, warnings, runtime issues |
| Smallness |
Component size |
Element count, script bloat, page complexity |
Low Weight (5% each)
| Principle |
Measures |
Indicators |
| Decomposability |
Isolation testing |
Component separation, modular design |
| Similarity |
Technology familiarity |
Standard frameworks, known patterns |
Assessment Workflow
1. Navigate to URL → 2. Collect Metrics → 3. Score Principles
↓
4. Generate JSON ← 5. Calculate Grades ← 6. Apply Weights
↓
7. Generate HTML Report with Radar Chart
↓
8. Open in Browser (auto-opens)
Output Files
tests/reports/
├── testability-results-<timestamp>.json # Raw data
├── testability-report-<timestamp>.html # Visual report
└── latest.json # Symlink
Integration Examples
CI/CD Integration
# GitHub Actions
- name: Testability Assessment
run: |
timeout 180 .claude/skills/testability-scoring/scripts/run-assessment.sh ${{ env.APP_URL }}
- name: Upload Reports
uses: actions/upload-artifact@v3
with:
name: testability-reports
path: tests/reports/testability-*.html
QX Partner Integration
// Combine testability with QX analysis
const qxAnalysis = await Task("QX Analysis", {
target: 'https://example.com',
integrateTestability: true
}, "qx-partner");
// Returns combined insights:
// - QX Score: 78/100
// - Testability Integration: Observability 72/100
// - Combined Insight: Low observability may mask UX issues
Programmatic Usage
import { runTestabilityAssessment } from './testability';
const results = await runTestabilityAssessment('https://example.com');
console.log(`Overall: ${results.overallScore}/100 (${results.grade})`);
console.log('Recommendations:', results.recommendations);
Agent Integration
// Run testability assessment
const assessment = await Task("Testability Assessment", {
url: 'https://example.com',
generateReport: true,
openBrowser: true
}, "qe-quality-analyzer");
// Use with QX Partner for holistic analysis
const qxReport = await Task("Full QX Analysis", {
target: 'https://example.com',
integrateTestability: true,
detectOracleProblems: true
}, "qx-partner");
Vibium Integration (Optional)
Overview
Vibium browser automation can be used alongside Playwright for enhanced testability assessment. While Playwright remains the primary engine, Vibium offers complementary capabilities for certain metrics.
Installation:
claude mcp add vibium -- npx -y vibium
Vibium-Enhanced Metrics
| Principle |
Vibium Enhancement |
Benefit |
| Observability |
Auto-wait duration tracking |
Measures DOM stability (30s timeout, 100ms polling) |
| Controllability |
Element interaction success rate |
Validates automation readiness via MCP |
| Stability |
Screenshot consistency |
Visual regression detection for layout stability |
| Explainability |
Element attribute extraction |
ARIA labels, semantic HTML validation |
When to Use Vibium
✅ USE Vibium for:
- Element stability metrics (auto-wait duration analysis)
- Visual consistency checks (screenshot comparison)
- MCP-native AI agent integration
- Lightweight Docker images (400MB vs 1.2GB)
❌ USE Playwright for:
- Console error detection (Vibium V1 lacks console API)
- Network performance metrics (BiDi network APIs coming in V2)
- Comprehensive browser coverage (Firefox, Safari)
- Production-proven stability (Vibium V1 released Dec 2024)
Hybrid Assessment Example
// Testability assessment using both engines
const assessment = {
// Playwright: Comprehensive metrics
playwright: await runPlaywrightAssessment(url),
// Vibium: Stability metrics
vibium: {
elementStability: await measureAutoWaitDuration(url),
visualConsistency: await compareScreenshots(url),
accessibilityAttributes: await extractARIALabels(url)
}
};
// Enhanced Observability Score
const observability =
(assessment.playwright.consoleErrors * 0.6) +
(assessment.vibium.elementStability * 0.4);
Vibium MCP Tools for Testability
// 1. Element Stability Measurement
const browser = await browser_launch();
await browser_navigate({ url });
const startTime = Date.now();
const element = await browser_find({ selector: ".critical-element" });
const autoWaitDuration = Date.now() - startTime;
// Lower duration = better stability
// 2. Visual Consistency Check
const screenshot1 = await browser_screenshot();
await browser_navigate({ url }); // Reload
const screenshot2 = await browser_screenshot();
const visualDiff = compareImages(screenshot1.png, screenshot2.png);
// Lower diff = better stability
// 3. Accessibility Attribute Extraction
const elements = await browser_find({ selector: "button, a, input" });
const ariaLabels = elements.map(el => el.attributes["aria-label"]);
const semanticScore = (ariaLabels.filter(Boolean).length / elements.length) * 100;
Migration Strategy
Current (V2.2): Hybrid approach
- Playwright: Primary engine for all 10 principles
- Vibium: Optional enhancement for stability metrics
Future (V3.0): When Vibium V2 ships
- Evaluate Vibium as primary engine if:
- Console/Network APIs available - Production stability proven - Community adoption increases
Agent Coordination Hints
Memory Namespace
aqe/testability/
├── assessments/* - Assessment results by URL
├── historical/* - Historical scores for trend analysis
├── recommendations/* - Improvement recommendations
├── integration/* - QX integration data
└── vibium/* - Vibium-specific metrics (optional)
Fleet Coordination
const testabilityFleet = await FleetManager.coordinate({
strategy: 'testability-assessment',
agents: [
'qe-quality-analyzer', // Primary assessment
'qx-partner', // UX integration
'qe-visual-tester' // Visual validation
],
topology: 'sequential'
});
Common Issues & Solutions
| Issue |
Solution |
| Tests timing out |
Increase timeout: timeout 300 ./scripts/run-assessment.sh URL |
| Partial results |
Check console errors, increase network timeout |
| Report not opening |
Use AUTO_OPEN=false, open manually |
| Config not updating |
Use TEST_URL env var instead |
| Vibium not available |
Install via claude mcp add vibium -- npx -y vibium (optional) |
| Hybrid mode errors |
Vibium is optional; assessments work without it |
Related Skills
- [accessibility-testing](../accessibility-testing/) - WCAG compliance (overlaps with Explainability)
- [visual-testing-advanced](../visual-testing-advanced/) - UI consistency
- [performance-testing](../performance-testing/) - Load time metrics
Credits & References
Framework Origin
Implementation
Vibium Resources
Remember
Testability is an investment, not an afterthought.
Good testability:
- Reduces debugging time
- Enables faster feedback loops
- Makes defects easier to find
- Supports continuous testing
Low scores = High risk. Prioritize improvements by weight × impact.