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testland/non-functional-requirement-extractor

Reads a PRD, design doc, or product brief and pulls out the non-functional requirements (performance, accessibility, security, internationalization, reliability, observability) as concrete, threshold-bound, testable assertions. Maps every NFR to its measurement source (Lighthouse, axe, OWASP ASVS, WCAG criterion, etc.) so the test suite knows what to assert against. Use after acceptance-criteria-extractor handles functional requirements.

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name:
non-functional-requirement-extractor
description:
Reads a PRD, design doc, or product brief and pulls out the non-functional requirements (performance, accessibility, security, internationalization, reliability, observability) as concrete, threshold-bound, testable assertions. Maps every NFR to its measurement source (Lighthouse, axe, OWASP ASVS, WCAG criterion, etc.) so the test suite knows what to assert against. Use after acceptance-criteria-extractor handles functional requirements.

non-functional-requirement-extractor

Overview

ISTQB defines non-functional testing as "A test type to evaluate that a component or system complies with non-functional requirements" (istqb-nft). The eight ISO/IEC 25010:2011 product-quality characteristics define the canonical NFR categories (cite by stable standard ID; iso.org is paywalled / Cloudflare-protected):

ISO/IEC 25010 characteristicCommon shorthandThis skill covers
Functional Suitabilityfunctional(out - handled by acceptance-criteria-extractor)
Performance Efficiencyperformance / perfyes
Compatibilitycompatibilityyes
Usabilitya11y / UXyes (a11y subset)
Reliabilityreliabilityyes
Securitysecurityyes
Maintainability(developer-facing)(out)
Portability(developer-facing)(out)

Plus two practitioner-emergent NFR families that are increasingly treated as first-class:

FamilySource
Internationalization (i18n)W3C i18n best practices
ObservabilityDORA / SRE practitioner literature

Acceptance-criteria-extractor handles functional requirements (Given/When/Then). This skill handles everything else - the threshold-and-measurement requirements that don't fit Gherkin's shape.

When to use

  • A PRD mentions "performance," "fast," "accessible," "secure," or similar - words that fail the Observable testability heuristic.
  • A team is shifting from informal to formal NFRs in tickets.
  • A non-functional regression is being added to a release plan and needs a measurable baseline.

How to use

  1. Confirm functional requirements are already covered by acceptance-criteria-extractor; this skill takes everything else.
  2. Scan the doc family-by-family for the Step 1 signal phrases.
  3. For each signal, run the Step 2 testability test: does it have a threshold, a measurement source, and a scope?
  4. Rewrite each testable signal as a threshold-bound assertion; never invent a missing number - flag it as a threshold gap instead.
  5. Map each NFR to its canonical measurement source per Step 3 (references/measurement-sources.md).
  6. Emit the Output-format tables plus a "Threshold gaps (HUMAN INPUT REQUIRED)" list, and return it to the author for confirmation.

Step 1 - Scan the doc for each NFR family

Per family, look for the canonical signal phrases:

FamilySignal phrases
Performance"fast", "responsive", "within Xms", "p95", "throughput", "latency", "time to"
Accessibility"WCAG", "screen reader", "keyboard navigation", "color contrast", "ARIA"
Security"auth", "encrypt", "OWASP", "CSP", "rate limit", "secret"
Compatibility"browser", "iOS", "Android", "version", "device"
Reliability"uptime", "SLO", "SLA", "graceful degradation", "circuit breaker", "retry"
Internationalization"locale", "RTL", "translation", "Unicode", "timezone"
Observability"metric", "log", "trace", "alert", "dashboard"

Each signal becomes a candidate NFR - but NOT every signal is testable as authored. Run each through Step 2.

Step 2 - Make every NFR threshold-bound

Per ISTQB testability (istqb-testability), an NFR is testable only when it has:

  1. A threshold (numeric or boolean).
  2. A measurement source (which tool / metric provides the value).
  3. A scope (which surface / user / scenario it applies to).
Untestable NFRThreshold-bound rewrite
"The site should be fast""p95 page-load time on /dashboard is ≤2.5s, measured by Lighthouse CI under 4G throttling."
"Accessible to screen reader users""WCAG 2.2 AA conformance on /checkout; axe-core scan returns zero serious or critical violations."
"Secure against attacks""OWASP ASVS Level 2 controls 1-7; verified by npm audit --audit-level=high exit zero AND ZAP baseline scan zero alerts."
"Works on all browsers""Functional E2E tests pass on Chrome ≥120, Firefox ≥120, Safari ≥17 (latest two majors per WebRumStats data)."
"Highly available""Uptime ≥99.9% measured monthly via external prober; recovery from any single-AZ failure ≤5 min."

The agent never fabricates a threshold. If the doc says "fast" without a number, the agent emits an explicit question ("What's the target p95? Common defaults: 2.5s for landing, 1.5s for cached, 200ms for API."), it does not invent 2.5s.

Step 3 - Map to canonical measurement sources

Each NFR must name how it's measured. Look up the canonical source for its family in references/measurement-sources.md, which catalogs sources for Performance (Web Vitals, k6), Accessibility (WCAG 2.2, axe-core), Security (OWASP ASVS, ZAP), Compatibility (MDN, Can I use), Reliability (Google SRE Workbook), and Internationalization (W3C i18n, Unicode CLDR).

Load-bearing defaults - Web Vitals: LCP ≤2.5s, INP ≤200ms, CLS ≤0.1. Per-criterion a11y citations use the WCAG SC ID format (WCAG 2.2 SC 1.4.3 Contrast (Minimum)) so the test report back-references the standard.

Output format

# NFRs extracted from `<doc-id>`

**Source doc:** `<path or URL>`
**Date extracted:** YYYY-MM-DD
**NFRs found:** N
**Threshold gaps flagged:** M

## Performance

| ID    | Requirement                                                | Threshold | Measurement | Scope                |
|-------|------------------------------------------------------------|-----------|-------------|----------------------|
| PRF-1 | LCP on /dashboard                                          | ≤2.5s     | Lighthouse CI; Web Vitals 75th-percentile field data | logged-in user, 4G, 1280x800 |
| PRF-2 | p95 latency on POST /api/orders                            | ≤200ms    | k6 load test, 50 RPS for 5 min | production-like staging |

## Accessibility

| ID    | Requirement                                                | Threshold        | Measurement | Scope            |
|-------|------------------------------------------------------------|------------------|-------------|------------------|
| A11Y-1| WCAG 2.2 AA conformance                                    | zero serious/critical violations | axe-core scan | every page in app sitemap |

## Security

| ID    | Requirement                                                | Threshold        | Measurement | Scope                  |
|-------|------------------------------------------------------------|------------------|-------------|------------------------|
| SEC-1 | No high-severity dependency vulnerabilities                | zero high/critical | npm audit --audit-level=high | every PR; production deps |
| SEC-2 | OWASP ASVS Level 2 baseline                                | pass              | ZAP baseline scan + manual ASVS checklist | release readiness gate |

## Compatibility / i18n / Reliability / Observability

(similar tables, only included when the source doc raised them)

## Threshold gaps (HUMAN INPUT REQUIRED)

| Vague phrase                       | Where in doc          | Suggested concretization                                       |
|------------------------------------|-----------------------|----------------------------------------------------------------|
| "fast checkout"                    | line 12               | LCP ≤1.5s (typical for cached transactional flow)?            |
| "supports global users"            | line 28               | Locale list? RTL support? Timezone handling? Unicode in fields? |

The agent does NOT pick the answers - author must confirm.

Worked example

A team submits a checkout PRD. The skill runs it through two passes.

Pass 1 - vague PRD. Input:

"Checkout must feel snappy and work for users worldwide. We need to meet enterprise security requirements."

Every phrase fails the Step 2 testability test, so nothing is emitted as an NFR - each becomes a threshold-gap question:

**NFRs found:** 0 (all phrases are vague)
**Threshold gaps flagged:** 3

| Vague phrase                              | Suggested concretization                                                                  |
|-------------------------------------------|-------------------------------------------------------------------------------------------|
| "feel snappy"                              | LCP ≤2.5s, INP ≤200ms (Web Vitals defaults)?                                            |
| "work for users worldwide"                 | Specify: which locales? RTL? timezones? Unicode validation? CLDR-based number/date formatting? |
| "enterprise security requirements"         | OWASP ASVS Level 2 (typical baseline) or Level 3 (strict)? SOC 2 Type II audit? FedRAMP? |

The output is a question list, not a fabricated set of thresholds.

Pass 2 - author returns with concrete thresholds. Input:

"Page load on /dashboard must be ≤1.5s p95 measured by Lighthouse CI on the GitHub Actions ubuntu-latest runner. Color contrast ratio ≥4.5:1 for normal text per WCAG 2.2 SC 1.4.3."

Every phrase is now threshold-bound and measurement-cited, so the skill emits tables with zero gaps:

## Performance

| ID    | Requirement                                                | Threshold | Measurement | Scope          |
|-------|------------------------------------------------------------|-----------|-------------|----------------|
| PRF-1 | Page load on /dashboard                                    | ≤1.5s p95 | Lighthouse CI on GitHub Actions ubuntu-latest | /dashboard route |

## Accessibility

| ID    | Requirement                                                | Threshold | Measurement | Scope          |
|-------|------------------------------------------------------------|-----------|-------------|----------------|
| A11Y-1| Color contrast ratio for normal text                       | ≥4.5:1    | WCAG 2.2 SC 1.4.3 | every page |

**Threshold gaps:** 0 - all NFRs are threshold-bound and measurement-cited.

Anti-patterns

Anti-patternWhy it failsFix
Inventing thresholds the doc didn't specifyTests pass for fabricated baselines; real users see worse perf.Flag as threshold gap; require author input.
One generic "performance" NFR for every pageDifferent surfaces have different budgets (cached vs non-cached).One NFR per measurable scope (route × viewport × auth state).
Mapping every security NFR to "OWASP Top 10"Top 10 is awareness-tier; ASVS is verifiable. Compliance maps to ASVS.Specify ASVS Level (1/2/3) and which controls.
Treating "uptime SLA" as a test requirementSLA is a runtime / monitoring concern, not a pre-deploy test.Map to monitoring metric + alert rule, not to a CI gate.

References

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testland
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