specification-phase

Transform natural language feature requests into structured specifications that enable planning and implementation through systematic classification, informed guess strategy, and minimal clarification approach.

This skill orchestrates the /specify phase, producing spec.md with measurable success criteria, classification flags for downstream workflows, and maximum 3 clarifications using informed guess heuristics for technical defaults.

Core responsibilities:

• Parse and normalize feature input to slug format (kebab-case, no filler words)
• Check roadmap integration to reuse existing context
• Load project documentation context (docs/project/) to prevent hallucination
• Classify feature with 4 flags (HAS_UI, IS_IMPROVEMENT, HAS_METRICS, HAS_DEPLOYMENT_IMPACT)
• Determine research depth based on complexity (FLAG_COUNT: 0→minimal, 1→standard, ≥2→full)
• Apply informed guess strategy for non-critical technical decisions
• Generate ≤3 clarifications (only scope/security critical)
• Write measurable success criteria (quantifiable, user-facing)

Inputs: User's feature description, existing roadmap entries, project docs (if exists), codebase context Outputs: specs/NNN-slug/spec.md, NOTES.md, state.yaml, updated roadmap (if FROM_ROADMAP=true) Expected duration: 10-15 minutes

Execute /specify workflow in 9 steps:

1. Parse and normalize input - Generate slug (remove filler words: "add", "create", "we want to"), assign feature number (NNN)
2. Check roadmap integration - Search roadmap for slug match, reuse context if found (saves ~10 minutes)
3. Load project documentation - Extract tech stack, API patterns, existing entities from docs/project/ (prevents hallucination)
4. Classify feature - Set HAS_UI, IS_IMPROVEMENT, HAS_METRICS, HAS_DEPLOYMENT_IMPACT flags using decision tree
5. Determine research depth - FLAG_COUNT → minimal (0), standard (1), full (≥2)
6. Apply informed guess strategy - Use defaults for performance (<500ms), rate limits (100/min), auth (OAuth2), retention (90d logs)
7. Generate clarifications - Max 3 critical clarifications (scope > security > UX > technical priority matrix)
8. Write success criteria - Measurable, quantifiable, user-facing outcomes (not tech-specific)
9. Generate artifacts and commit - Create spec.md, NOTES.md, state.yaml, update roadmap

Key principle: Use informed guesses for non-critical decisions, document assumptions, limit clarifications to ≤3.

Before executing /specify phase:

• Git working tree clean (no uncommitted changes)
• Not on main branch (create feature branch: feature/NNN-slug)
• Required templates exist in .spec-flow/templates/
• If project docs exist, docs/project/ directory accessible

Required understanding before execution:

• Classification decision tree: UI keywords vs backend-only exclusions, improvement = baseline + target, metrics = user tracking, deployment = env vars/migrations/breaking changes
• Informed guess heuristics: Performance (<500ms), retention (90d logs, 365d analytics), rate limits (100/min), auth (OAuth2), error handling (user-friendly + error ID)
• Clarification prioritization matrix: Critical (scope, security, breaking changes) > High (UX) > Medium (performance SLA, tech stack) > Low (error messages, rate limits)
• Slug generation rules: Remove filler words, lowercase kebab-case, 50 char limit, fuzzy match roadmap

See reference.md for complete decision trees and heuristics.

- **Over-clarification**: >3 clarifications indicates missing informed guesses (check reference.md for defaults) - **Wrong classification**: Backend workers/APIs with HAS_UI=true wastes time generating UI artifacts - **Roadmap mismatch**: Filler words in slug prevent roadmap match ("add-student-dashboard" vs "student-dashboard") - **Vague success criteria**: "Works correctly", "is fast", "looks good" are not measurable - use quantifiable metrics **Parse and Normalize Input**

Extract feature description and generate clean slug.

Slug Generation Rules:

# Remove filler words and normalize
echo "$ARGUMENTS" |
  sed 's/\bwe want to\b//gi; s/\bI want to\b//gi' |
  sed 's/\badd\b//gi; s/\bcreate\b//gi; s/\bimplement\b//gi' |
  sed 's/\bget our\b//gi; s/\bto a\b//gi; s/\bwith\b//gi' |
  tr '[:upper:]' '[:lower:]' |
  sed 's/[^a-z0-9-]/-/g' | sed 's/--*/-/g' | sed 's/^-//;s/-$//' |
  cut -c1-50

Example:

• Input: "We want to add student progress dashboard"
• Slug: student-progress-dashboard ✅
• Number: 042
• Directory: specs/042-student-progress-dashboard/

Quality Check: Slug is concise, descriptive, no filler words, matches roadmap format.

See reference.md § Slug Generation Rules for detailed normalization logic.

**Check Roadmap Integration**

Search roadmap for existing entry to reuse context.

Detection Logic:

SLUG="student-progress-dashboard"
if grep -qi "^### ${SLUG}" .spec-flow/memory/roadmap.md; then
  FROM_ROADMAP=true
  # Extract requirements, area, role, impact/effort scores
  # Move entry from "Backlog"/"Next" to "In Progress"
  # Add branch and spec links
fi

Benefits:

• Saves ~10 minutes (requirements already documented)
• Automatic status tracking (roadmap updates)
• Context reuse (user already vetted scope)

Quality Check: If roadmap match found, extracted requirements appear in spec.md.

See reference.md § Roadmap Integration for fuzzy matching logic.

**Load Project Documentation Context**

Extract architecture constraints from docs/project/ to prevent hallucination.

Detection:

if [ -d "docs/project" ]; then
  HAS_PROJECT_DOCS=true
  # Extract tech stack, API patterns, entities
else
  echo "ℹ️  No project documentation (run /init-project recommended)"
  HAS_PROJECT_DOCS=false
fi

Extraction:

# Extract constraints from project docs
FRONTEND=$(grep -A 1 "| Frontend" docs/project/tech-stack.md | tail -1)
DATABASE=$(grep -A 1 "| Database" docs/project/tech-stack.md | tail -1)
API_STYLE=$(grep -A 1 "## API Style" docs/project/api-strategy.md | tail -1)
ENTITIES=$(grep -oP '[A-Z_]+(?= \{)' docs/project/data-architecture.md)

Document in NOTES.md:

## Project Documentation Context

**Tech Stack Constraints** (from tech-stack.md):

- Frontend: Next.js 14
- Database: PostgreSQL

**Spec Requirements**:

- ✅ MUST use documented tech stack
- ✅ MUST follow API patterns from api-strategy.md
- ✅ MUST check for duplicate entities before proposing new ones
- ❌ MUST NOT hallucinate MongoDB if PostgreSQL is documented

Quality Check: NOTES.md includes project context section with constraints.

Skip if: No docs/project/ directory exists (warn user but don't block).

**Classify Feature**

Set classification flags using decision tree.

Classification Logic:

HAS_UI (user-facing screens/components):

UI keywords: screen, page, dashboard, form, modal, component, frontend, interface
  → BUT NOT backend-only: API, endpoint, service, worker, cron, job, migration, health check
  → HAS_UI = true

Example: "Add student dashboard" → HAS_UI = true ✅
Example: "Add background worker" → HAS_UI = false ✅ (backend-only)

IS_IMPROVEMENT (optimization with measurable baseline):

Improvement keywords: improve, optimize, enhance, speed up, reduce time
  AND baseline: existing, current, slow, faster, better
  → IS_IMPROVEMENT = true

Example: "Improve search performance from 3.2s to <500ms" → IS_IMPROVEMENT = true ✅
Example: "Make search faster" → IS_IMPROVEMENT = false ❌ (no baseline)

HAS_METRICS (user behavior tracking):

Metrics keywords: track user, measure user, engagement, retention, conversion, analytics, A/B test
  → HAS_METRICS = true

Example: "Track dashboard engagement" → HAS_METRICS = true ✅

HAS_DEPLOYMENT_IMPACT (env vars, migrations, breaking changes):

Deployment keywords: migration, schema change, env variable, breaking change, docker, platform change
  → HAS_DEPLOYMENT_IMPACT = true

Example: "OAuth authentication (needs env vars)" → HAS_DEPLOYMENT_IMPACT = true ✅

Quality Check: Classification matches feature intent. No UI artifacts for backend workers.

See reference.md § Classification Decision Tree for complete logic.

**Determine Research Depth**

Select research depth based on complexity (FLAG_COUNT).

Research Depth Guidelines:

FLAG_COUNT	Depth	Tools	Use Cases
0	Minimal	1-2	Simple backend endpoint, config change
1	Standard	3-5	Single-aspect feature (UI-only or backend-only)
≥2	Full	5-8	Complex multi-aspect feature

Minimal Research (FLAG_COUNT = 0):

1. Constitution check (alignment with mission/values)
2. Grep for similar patterns

Standard Research (FLAG_COUNT = 1): 1-2. Minimal research 3. UI inventory scan (if HAS_UI=true) 4. Performance budgets check 5. Similar spec search

Full Research (FLAG_COUNT ≥ 2): 1-5. Standard research 6. Design inspirations (if HAS_UI=true) 7. Web search for novel patterns 8. Integration points analysis

Quality Check: Research depth matches complexity. Don't over-research simple features.

See reference.md § Research Depth Guidelines for tool selection logic.

**Apply Informed Guess Strategy**

Use defaults for non-critical technical decisions.

Use Informed Guesses For (do NOT clarify):

• Performance targets: API <500ms (95th percentile), Frontend FCP <1.5s, TTI <3.0s
• Data retention: User data indefinite (with deletion option), Logs 90 days, Analytics 365 days
• Error handling: User-friendly messages + error ID (ERR-XXXX), logging to error-log.md
• Rate limiting: 100 requests/minute per user, 1000/minute per IP
• Authentication: OAuth2 for users, JWT for APIs, MFA optional (users), required (admins)
• Integration patterns: RESTful API (unless GraphQL needed), JSON format, offset/limit pagination

Document Assumptions in spec.md:

## Performance Targets (Assumed)

- API endpoints: <500ms (95th percentile)
- Frontend FCP: <1.5s, TTI: <3.0s
- Lighthouse: Performance ≥85, Accessibility ≥95

_Assumption: Standard web application performance expectations applied._

Do NOT Use Informed Guesses For:

• Scope-defining decisions (feature boundary, user roles)
• Security/privacy critical choices (encryption, PII handling)
• Breaking changes (API response format changes)
• No reasonable default exists (business logic decisions)

Quality Check: No clarifications for decisions with industry-standard defaults.

See reference.md § Informed Guess Heuristics for complete defaults catalog.

**Generate Clarifications (Max 3)**

Identify ambiguities that cannot be reasonably assumed.

Clarification Prioritization Matrix:

Category	Priority	Ask?	Example
Scope boundary	Critical	✅ Always	"Does this include admin features or only user features?"
Security/Privacy	Critical	✅ Always	"Should PII be encrypted at rest?"
Breaking changes	Critical	✅ Always	"Is it okay to change the API response format?"
User experience	High	✅ If ambiguous	"Should this be a modal or new page?"
Performance SLA	Medium	❌ Use defaults	"What's the target response time?" → Assume <500ms
Technical stack	Medium	❌ Defer to plan	"Which database?" → Planning-phase decision
Error messages	Low	❌ Use standard	"What error message?" → Standard pattern
Rate limits	Low	❌ Use defaults	"How many requests?" → 100/min default

Limit: Maximum 3 clarifications total

Process:

1. Identify all ambiguities
2. Rank by category priority
3. Keep top 3 most critical
4. Make informed guesses for remaining
5. Document assumptions clearly

Good Clarifications:

[NEEDS CLARIFICATION: Should dashboard show all students or only assigned classes?]
[NEEDS CLARIFICATION: Should parents have access to this dashboard?]

Bad Clarifications (have defaults):

❌ [NEEDS CLARIFICATION: What's the target response time?] → Use 500ms default
❌ [NEEDS CLARIFICATION: Which database to use?] → Planning-phase decision
❌ [NEEDS CLARIFICATION: What error message format?] → Use standard pattern

Quality Check: ≤3 clarifications total, all are scope/security/UX critical.

See reference.md § Clarification Prioritization Matrix for complete ranking system.

**Write Success Criteria**

Define measurable, quantifiable, user-facing outcomes.

Good Criteria Format:

## Success Criteria

- User can complete registration in <3 minutes (measured via PostHog funnel)
- API response time <500ms for 95th percentile (measured via Datadog APM)
- Lighthouse accessibility score ≥95 (measured via CI Lighthouse check)
- 95% of user searches return results in <1 second

Criteria Requirements:

• Measurable: Can be validated objectively
• Quantifiable: Has specific numeric target
• User-facing: Focuses on outcomes, not implementation
• Measurement method: Specifies how to validate (tool, metric)

Bad Criteria to Avoid:

❌ System works correctly (not measurable)
❌ API is fast (not quantifiable)
❌ UI looks good (subjective)
❌ React components render efficiently (technology-specific, not outcome-focused)

Quality Check: Every criterion is measurable, quantifiable, and outcome-focused.

**Generate Artifacts and Commit**

Create specification artifacts and commit to git.

Artifacts:

1. specs/NNN-slug/spec.md - Structured specification with classification flags, requirements, assumptions, clarifications (≤3), success criteria
2. specs/NNN-slug/NOTES.md - Implementation decisions and project context
3. specs/NNN-slug/visuals/README.md - Visual artifacts directory (if HAS_UI=true)
4. specs/NNN-slug/state.yaml - Phase state tracking (currentPhase: specification, status: completed)
5. Updated roadmap (if FROM_ROADMAP=true) - Move entry to "In Progress", add branch/spec links

Validation Checks:

• Requirements checklist complete (if exists)
• Clarifications ≤3
• Classification flags match feature description
• Success criteria are measurable
• Roadmap updated (if FROM_ROADMAP=true)

Commit Message:

git add specs/NNN-slug/
git commit -m "feat: add spec for <feature-name>

Generated specification with classification:
- HAS_UI: <true/false>
- IS_IMPROVEMENT: <true/false>
- HAS_METRICS: <true/false>
- HAS_DEPLOYMENT_IMPACT: <true/false>

Clarifications: N
Research depth: <minimal/standard/full>"

Quality Check: All artifacts created, spec committed, roadmap updated, state.yaml initialized.

**Pre-phase checks**: - [ ] Git working tree clean - [ ] Not on main branch - [ ] Required templates exist

During phase:

• Slug normalized (no filler words, lowercase kebab-case)
• Roadmap checked for existing entry
• Project docs loaded (if exist)
• Classification flags validated (no conflicting keywords)
• Research depth appropriate for complexity (FLAG_COUNT-based)
• Clarifications ≤3 (use informed guesses for rest)
• Success criteria measurable and quantifiable
• Assumptions documented clearly

Post-phase validation:

• spec.md committed with proper message
• NOTES.md initialized
• Roadmap updated (if FROM_ROADMAP=true)
• visuals/ created (if HAS_UI=true)
• state.yaml initialized

**Specification quality targets**:

• Clarifications: ≤3 per spec
• Classification accuracy: ≥90%
• Success criteria: 100% measurable
• Time to spec: ≤15 minutes
• Rework rate: <5%

What makes a good spec:

• Clear scope boundaries (what's in, what's out)
• Measurable success criteria (with measurement methods)
• Reasonable assumptions documented
• Minimal clarifications (only critical scope/security)
• Correct classification (matches feature intent)
• Context reuse (from roadmap when available)

What makes a bad spec:

• 5 clarifications (over-clarifying technical defaults)

• Vague success criteria ("works correctly", "is fast")
• Technology-specific criteria (couples to implementation)
• Wrong classification (UI flag for backend-only)
• Missing roadmap integration (duplicates planning work)

**Impact**: Delays planning phase, frustrates users

Scenario:

Spec with 7 clarifications (limit: 3):
- [NEEDS CLARIFICATION: What format? CSV or JSON?] → Use JSON default
- [NEEDS CLARIFICATION: Rate limiting strategy?] → Use 100/min default
- [NEEDS CLARIFICATION: Maximum file size?] → Use 50MB default

Prevention:

• Use industry-standard defaults (see reference.md § Informed Guess Heuristics)
• Only mark critical scope/security decisions as NEEDS CLARIFICATION
• Document assumptions in spec.md "Assumptions" section
• Prioritize by impact: scope > security > UX > technical

If encountered: Reduce to 3 most critical, convert others to documented assumptions.

**Impact**: Creates unnecessary UI artifacts, wastes time

Scenario:

Feature: "Add background worker to process uploads"
Classified: HAS_UI=true (WRONG - no user-facing UI)
Result: Generated screens.yaml for backend-only feature

Root cause: Keyword "process" triggered false positive without checking for backend-only keywords

Prevention:

1. Check for backend-only keywords: worker, cron, job, migration, health check, API, endpoint, service
2. Require BOTH UI keyword AND absence of backend-only keywords
3. Use classification decision tree (see reference.md § Classification Decision Tree)

**Impact**: Misses context reuse opportunity, duplicates planning work

Scenario:

User input: "We want to add Student Progress Dashboard"
Generated slug: "add-student-progress-dashboard" (BAD - includes "add")
Roadmap entry: "### student-progress-dashboard" (slug without "add")
Result: No match found, created fresh spec instead of reusing roadmap context

Prevention:

1. Remove filler words during slug generation: "add", "create", "we want to"
2. Normalize to lowercase kebab-case consistently
3. Offer fuzzy matches if exact match not found

**Impact**: Wastes time, exceeds token budget

Scenario:

# 15 research tools for simple backend endpoint (WRONG)
Glob *.py, Glob *.ts, Glob *.tsx, Grep "database", Grep "model"...

Prevention:

• Use research depth guidelines: FLAG_COUNT = 0 → 1-2 tools only
• For simple features: Constitution check + pattern search is sufficient
• Reserve full research (5-8 tools) for complex multi-aspect features

Correct approach:

# 2 research tools for simple backend endpoint (CORRECT)
grep "similar endpoint" specs/*/spec.md
grep "BaseModel" api/app/models/*.py

**Impact**: Cannot validate implementation, leads to scope creep

Bad examples:

❌ System works correctly (not measurable)
❌ API is fast (not quantifiable)
❌ UI looks good (subjective)

Good examples:

✅ User can complete registration in <3 minutes (measured via PostHog funnel)
✅ API response time <500ms for 95th percentile (measured via Datadog APM)
✅ Lighthouse accessibility score ≥95 (measured via CI Lighthouse check)

Prevention: Every criterion must answer: "How do we measure this objectively?"

**Impact**: Couples spec to implementation details, reduces flexibility

Bad examples:

❌ React components render efficiently
❌ Redis cache hit rate >80%
❌ PostgreSQL queries use proper indexes

Good examples (outcome-focused):

✅ Page load time <1.5s (First Contentful Paint)
✅ 95% of user searches return results in <1 second
✅ Database queries complete in <100ms average

Prevention: Focus on user-facing outcomes, not implementation mechanisms.

**When to use**:

• Non-critical technical decisions
• Industry standards exist
• Default won't impact scope or security

When NOT to use:

• Scope-defining decisions
• Security/privacy critical choices
• No reasonable default exists

Approach:

1. Check if decision has reasonable default (see reference.md § Informed Guess Heuristics)
2. Document assumption clearly in spec
3. Note that user can override if needed

Example:

## Performance Targets (Assumed)

- API response time: <500ms (95th percentile)
- Frontend FCP: <1.5s
- Database queries: <100ms

**Assumptions**:

- Standard web app performance expectations applied
- If requirements differ, specify in "Performance Requirements" section

Result: Reduces clarifications from 5-7 to 0-2, saves ~10 minutes

**When to use**:

• Feature name matches roadmap entry
• Roadmap uses consistent slug format

Approach:

1. Normalize user input to slug format
2. Search roadmap for exact match
3. If found: Extract requirements, area, role, impact/effort
4. Move to "In Progress" section automatically
5. Add branch and spec links

Result: Saves ~10 minutes, requirements already vetted, automatic status tracking

**Best practice**: Follow decision tree systematically (see reference.md § Classification Decision Tree)

Process:

1. Check UI keywords → Set HAS_UI (but verify no backend-only exclusions)
2. Check improvement keywords + baseline → Set IS_IMPROVEMENT
3. Check metrics keywords → Set HAS_METRICS
4. Check deployment keywords → Set HAS_DEPLOYMENT_IMPACT

Result: 90%+ classification accuracy, correct artifacts generated

Specification phase complete when:

• All pre-phase checks passed
• All 9 execution steps completed
• All post-phase validations passed
• Spec committed to git
• state.yaml shows currentPhase: specification and status: completed

Ready to proceed when:

• If clarifications >0 → Run /clarify
• If clarifications = 0 → Run /plan

**Issue**: Too many clarifications (>3) **Solution**: Review reference.md § Informed Guess Heuristics for defaults, convert non-critical questions to assumptions

Issue: Classification seems wrong Solution: Re-check decision tree, verify no backend-only keywords for HAS_UI=true

Issue: Roadmap entry exists but wasn't matched Solution: Check slug normalization, offer fuzzy matches, update roadmap slug format

Issue: Success criteria are vague Solution: Add quantifiable metrics and measurement methods, focus on user-facing outcomes

Issue: Research depth excessive for simple feature Solution: Follow FLAG_COUNT guidelines (0→minimal, 1→standard, ≥2→full)

Issue: Project context missing/incomplete Solution: Run /init-project to generate docs/project/, or manually create tech-stack.md and api-strategy.md

For detailed documentation:

Classification & Defaults: reference.md

• Classification decision tree (HAS_UI, IS_IMPROVEMENT, HAS_METRICS, HAS_DEPLOYMENT_IMPACT)
• Informed guess heuristics (performance, retention, auth, rate limits)
• Clarification prioritization matrix (scope > security > UX > technical)
• Slug generation rules (normalization, filler word removal)

Real-World Examples: examples.md

• Good specs (0-2 clarifications) vs bad specs (>5 clarifications)
• Side-by-side comparisons with analysis
• Progressive learning patterns (features 1-5, 6-15, 16+)
• Classification accuracy examples

Execution Details: reference.md § Research Depth Guidelines, Common Mistakes to Avoid

Next phase after /specify:

• If clarifications >0 → /clarify (reduces ambiguity via targeted questions)
• If clarifications = 0 → /plan (generates design artifacts from spec)