/prd-master
PRD writing and product definition expert. Use when writing PRDs, user stories, acceptance criteria, or prioritizing features. Covers RICE/MoSCoW frameworks, agile requirements, and specification best practices.
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/prd-master
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PRD writing and product definition expert. Use when writing PRDs, user stories, acceptance criteria, or prioritizing features. Covers RICE/MoSCoW frameworks, agile requirements, and specification best practices.
SKILL.md
prd-master.SKILL.mdname: prd-master
description: PRD writing and product definition expert. Use when writing PRDs, user stories, acceptance criteria, or prioritizing features. Covers RICE/MoSCoW frameworks, agile requirements, and specification best practices.
PRD Master
Core Principles
- **Living Document** — PRDs evolve throughout product lifecycle
- **Stakeholder Collaboration** — Early involvement prevents late rework
- **Measurable Goals** — Replace vague with quantifiable targets
- **Focused yet Flexible** — Lean structure enables adaptation
- **Problem-First** — Define the problem before jumping to solutions
- **User-Centered** — Ground decisions in user research and data
---
Hard Rules (Must Follow)
> These rules are mandatory. Violating them means the skill is not working correctly.
No Vague Metrics
**All metrics and requirements must be quantifiable. Vague descriptions are forbidden.**
❌ FORBIDDEN:
- "The app should be fast"
- "Support many users"
- "Good user experience"
- "The system should be reliable"
- "Easy to use interface"
✅ REQUIRED:
- "Page load time < 2s on 4G, < 500ms on WiFi (P95)"
- "Support 10,000 concurrent users with 99.9% uptime"
- "NPS > 50, Task completion rate > 85%"
- "99.9% availability, MTTR < 1 hour"
- "User can complete checkout in < 3 clicks"
Problem Before Solution
**Never propose a solution without clearly defining the problem first.**
❌ FORBIDDEN:
"We should add a search bar to the navigation"
✅ REQUIRED:
"Problem: Users can't find products quickly (40% exit rate on catalog).
They need a way to filter 1000+ products by attributes.
Proposed solutions: search bar, smart filters, AI recommendations."
INVEST-Compliant Stories
**All user stories must pass the INVEST criteria checklist.**
❌ FORBIDDEN:
- Dependent stories that can't be delivered independently
- Stories without acceptance criteria
- Stories too large to complete in one sprint
- Stories without clear user value
✅ REQUIRED:
- [ ] Independent — Can be delivered alone
- [ ] Negotiable — Details can be discussed
- [ ] Valuable — Clear user/business value
- [ ] Estimable — Team can estimate effort
- [ ] Small — Fits in one sprint
- [ ] Testable — Has acceptance criteria
---
Quick Reference
When to Use What
| Scenario | Approach | Tool/Framework | |----------|----------|----------------| | Feature prioritization | Scoring model | RICE, ICE | | Release planning | Must/Should/Could/Won't | MoSCoW | | Customer satisfaction | Delight vs basics | Kano Model | | Sprint planning | User stories + BDD | Given-When-Then | | Complex requirements | Traditional PRD | Full template | | Agile iteration | Lean requirements | User stories + acceptance criteria |
---
PRD Structure
Essential Components
## 1. Executive Summary
- Problem statement (2-3 sentences)
- Proposed solution (1-2 sentences)
- Success metrics (3-5 key metrics)
## 2. Context & Background
- Why now? Market opportunity or user pain
- Strategic alignment with company goals
- What happens if we don't build this?
## 3. Goals & Success Metrics
- Business objectives (revenue, retention, growth)
- User objectives (satisfaction, engagement)
- Success criteria (quantifiable targets)
## 4. Target Users & Personas
- Primary users (who benefits most?)
- Secondary users (indirect beneficiaries)
- User needs, pain points, motivations
- Jobs to be done
## 5. User Stories & Use Cases
- Core user flows
- Edge cases and error scenarios
- Integration with existing features
## 6. Requirements
- Functional requirements (what it does)
- Non-functional requirements (performance, security)
- Acceptance criteria (how we verify)
## 7. Out of Scope
- What we're explicitly NOT building
- Future considerations for later phases
## 8. Design & UX
- Link to design files (Figma, etc.)
- Key design decisions
- Accessibility requirements (WCAG 2.2 AA)
## 9. Technical Considerations
- Architecture overview
- Dependencies and integrations
- Data model changes
- API contracts
## 10. Rollout & Launch Plan
- Phased rollout strategy
- Feature flags and A/B tests
- Monitoring and alerts
- Rollback plan
## 11. Open Questions & Risks
- Unknowns requiring research
- Technical risks and mitigations
- Dependencies on other teams
---
User Story Writing
Standard Format
As a [persona/role],
I want to [action/goal],
So that [benefit/value].
The Three C's
Card — Brief description on index card
→ Captures essence, not details
→ Placeholder for conversation
Conversation — Discussion between team members
→ Explore edge cases
→ Clarify assumptions
→ Uncover hidden requirements
Confirmation — Acceptance criteria
→ Defines "done"
→ Testable conditions
→ Given-When-Then formatINVEST Criteria
Independent — Story stands alone, minimal dependencies
Negotiable — Details emerge through conversation
Valuable — Delivers value to users or business
Estimable — Team can estimate effort
Small — Completable within one sprint
Testable — Clear acceptance criteria
Examples
## Good User Stories
### Feature: Password Reset
As a user who forgot my password,
I want to reset it via email,
So that I can regain access to my account without contacting support.
**Acceptance Criteria:**
- Given I'm on the login page
- When I click "Forgot Password"
- Then I see a form requesting my email address
- Given I've entered my registered email
- When I submit the form
- Then I receive a password reset link within 2 minutes
- Given I click the reset link within 24 hours
- When I set a new password (min 8 chars, 1 number, 1 symbol)
- Then I'm logged in automatically
### Feature: Bulk Upload
As a content manager,
I want to upload multiple products via CSV,
So that I can save time compared to manual entry.
**Acceptance Crit
Read more
name: prd-master description: PRD writing and product definition expert. Use when writing PRDs, user stories, acceptance criteria, or prioritizing features. Covers RICE/MoSCoW frameworks, agile requirements, and specification best practices.
PRD Master
Core Principles
- **Living Document** — PRDs evolve throughout product lifecycle
- **Stakeholder Collaboration** — Early involvement prevents late rework
- **Measurable Goals** — Replace vague with quantifiable targets
- **Focused yet Flexible** — Lean structure enables adaptation
- **Problem-First** — Define the problem before jumping to solutions
- **User-Centered** — Ground decisions in user research and data
---
Hard Rules (Must Follow)
> These rules are mandatory. Violating them means the skill is not working correctly.
No Vague Metrics
**All metrics and requirements must be quantifiable. Vague descriptions are forbidden.**
❌ FORBIDDEN: - "The app should be fast" - "Support many users" - "Good user experience" - "The system should be reliable" - "Easy to use interface" ✅ REQUIRED: - "Page load time < 2s on 4G, < 500ms on WiFi (P95)" - "Support 10,000 concurrent users with 99.9% uptime" - "NPS > 50, Task completion rate > 85%" - "99.9% availability, MTTR < 1 hour" - "User can complete checkout in < 3 clicks"
Problem Before Solution
**Never propose a solution without clearly defining the problem first.**
❌ FORBIDDEN: "We should add a search bar to the navigation" ✅ REQUIRED: "Problem: Users can't find products quickly (40% exit rate on catalog). They need a way to filter 1000+ products by attributes. Proposed solutions: search bar, smart filters, AI recommendations."
INVEST-Compliant Stories
**All user stories must pass the INVEST criteria checklist.**
❌ FORBIDDEN: - Dependent stories that can't be delivered independently - Stories without acceptance criteria - Stories too large to complete in one sprint - Stories without clear user value ✅ REQUIRED: - [ ] Independent — Can be delivered alone - [ ] Negotiable — Details can be discussed - [ ] Valuable — Clear user/business value - [ ] Estimable — Team can estimate effort - [ ] Small — Fits in one sprint - [ ] Testable — Has acceptance criteria
---
Quick Reference
When to Use What
| Scenario | Approach | Tool/Framework | |----------|----------|----------------| | Feature prioritization | Scoring model | RICE, ICE | | Release planning | Must/Should/Could/Won't | MoSCoW | | Customer satisfaction | Delight vs basics | Kano Model | | Sprint planning | User stories + BDD | Given-When-Then | | Complex requirements | Traditional PRD | Full template | | Agile iteration | Lean requirements | User stories + acceptance criteria |
---
PRD Structure
Essential Components
## 1. Executive Summary - Problem statement (2-3 sentences) - Proposed solution (1-2 sentences) - Success metrics (3-5 key metrics) ## 2. Context & Background - Why now? Market opportunity or user pain - Strategic alignment with company goals - What happens if we don't build this? ## 3. Goals & Success Metrics - Business objectives (revenue, retention, growth) - User objectives (satisfaction, engagement) - Success criteria (quantifiable targets) ## 4. Target Users & Personas - Primary users (who benefits most?) - Secondary users (indirect beneficiaries) - User needs, pain points, motivations - Jobs to be done ## 5. User Stories & Use Cases - Core user flows - Edge cases and error scenarios - Integration with existing features ## 6. Requirements - Functional requirements (what it does) - Non-functional requirements (performance, security) - Acceptance criteria (how we verify) ## 7. Out of Scope - What we're explicitly NOT building - Future considerations for later phases ## 8. Design & UX - Link to design files (Figma, etc.) - Key design decisions - Accessibility requirements (WCAG 2.2 AA) ## 9. Technical Considerations - Architecture overview - Dependencies and integrations - Data model changes - API contracts ## 10. Rollout & Launch Plan - Phased rollout strategy - Feature flags and A/B tests - Monitoring and alerts - Rollback plan ## 11. Open Questions & Risks - Unknowns requiring research - Technical risks and mitigations - Dependencies on other teams
---
User Story Writing
Standard Format
As a [persona/role], I want to [action/goal], So that [benefit/value].
The Three C's
Card — Brief description on index card
→ Captures essence, not details
→ Placeholder for conversation
Conversation — Discussion between team members
→ Explore edge cases
→ Clarify assumptions
→ Uncover hidden requirements
Confirmation — Acceptance criteria
→ Defines "done"
→ Testable conditions
→ Given-When-Then formatINVEST Criteria
Independent — Story stands alone, minimal dependencies Negotiable — Details emerge through conversation Valuable — Delivers value to users or business Estimable — Team can estimate effort Small — Completable within one sprint Testable — Clear acceptance criteria
Examples
## Good User Stories ### Feature: Password Reset As a user who forgot my password, I want to reset it via email, So that I can regain access to my account without contacting support. **Acceptance Criteria:** - Given I'm on the login page - When I click "Forgot Password" - Then I see a form requesting my email address - Given I've entered my registered email - When I submit the form - Then I receive a password reset link within 2 minutes - Given I click the reset link within 24 hours - When I set a new password (min 8 chars, 1 number, 1 symbol) - Then I'm logged in automatically ### Feature: Bulk Upload As a content manager, I want to upload multiple products via CSV, So that I can save time compared to manual entry. **Acceptance Crit
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Repo: majiayu000/spellbook
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