Vibecosystem user-story-generator
User story generation - INVEST criteria, acceptance criteria (BDD/Given-When-Then), story mapping, epic decomposition, edge case stories, NFR stories
install
source · Clone the upstream repo
git clone https://github.com/vibeeval/vibecosystem
Claude Code · Install into ~/.claude/skills/
T=$(mktemp -d) && git clone --depth=1 https://github.com/vibeeval/vibecosystem "$T" && mkdir -p ~/.claude/skills && cp -r "$T/skills/user-story-generator" ~/.claude/skills/vibeeval-vibecosystem-user-story-generator && rm -rf "$T"
manifest:
skills/user-story-generator/SKILL.mdsource content
User Story Generator
User Story Format
Standard Format
As a [role/persona], I want [goal/feature], so that [benefit/value].
Extended Format (with context)
As a [role/persona], In the context of [situation/scenario], I want [goal/feature], so that [benefit/value].
Examples
As a new user, I want to sign up with my email and password, so that I can create an account and start using the service. As a team admin, In the context of onboarding a new team member, I want to invite users via email, so that they can join the workspace without manual account creation. As an API consumer, I want to authenticate with an API key, so that I can securely access resources programmatically.
INVEST Criteria
Checklist
| Criteria | Question | Example (Iyi) | Example (Kotu) |
|---|---|---|---|
| Independent | Can it be developed without other stories? | "User can reset password" | "User can reset password (requires email service story)" |
| Negotiable | Is implementation flexible? | "User can search products" | "User searches with Elasticsearch 8.x using fuzzy match" |
| Valuable | Does it deliver user/business value? | "User can export data as CSV" | "Refactor database schema" |
| Estimable | Can the team estimate it? | "User can upload a profile photo" | "Improve system performance" |
| Small | Can it be done in one sprint? | "User can add item to cart" | "User can complete entire checkout flow" |
| Testable | Can we verify it's done? | "Login with wrong password shows error message" | "System should be user-friendly" |
INVEST Validation
## Story: [story title] ### INVEST Check - [ ] **Independent:** No hard dependency on other stories - [ ] **Negotiable:** Multiple implementation approaches possible - [ ] **Valuable:** Clear end-user or business value - [ ] **Estimable:** Team can estimate within 1 story point range - [ ] **Small:** Fits within a single sprint - [ ] **Testable:** Clear pass/fail acceptance criteria
Acceptance Criteria (Given-When-Then / BDD)
Format
Scenario: [descriptive scenario name] Given [precondition / initial state] And [additional precondition if needed] When [action / trigger] And [additional action if needed] Then [expected result / assertion] And [additional assertion if needed] But [exception / negative assertion if needed]
Complete Example
Feature: Shopping Cart Scenario: Add item to empty cart Given the user is logged in And the cart is empty When the user clicks "Add to Cart" on a product Then the cart should contain 1 item And the cart badge should show "1" And the cart total should equal the product price Scenario: Add same item twice Given the user has 1 unit of "Widget A" in the cart When the user clicks "Add to Cart" on "Widget A" again Then the cart should show 2 units of "Widget A" And the cart total should be 2x the unit price But a duplicate line item should NOT be created Scenario: Add item when not logged in Given the user is not logged in When the user clicks "Add to Cart" Then the item should be saved to a guest cart (cookie-based) And the user should NOT be redirected to login And the guest cart should merge on login Scenario: Add out-of-stock item Given the product "Widget B" has 0 stock When the user views "Widget B" Then the "Add to Cart" button should be disabled And a "Notify me" option should be shown
Acceptance Criteria Anti-Patterns
| Anti-Pattern | Neden Yanlis | Dogru Yol |
|---|---|---|
| "Should work properly" | Tanimsiz | Specify exact expected behavior |
| Implementation details | Cozumu kisitlar | "Data persists" not "saves to PostgreSQL" |
| Missing error cases | Incomplete spec | Add scenarios for every failure mode |
| Too many scenarios (10+) | Story too big | Split the story |
| No performance criteria | NFR eksik | Add "within 2 seconds" where needed |
| Duplicate of another story | Redundancy | Reference, don't repeat |
Story Mapping
Story Map Structure
User Journey (left to right) ───────────────────────────────────── Activities: | Discovery | Purchase | Support | ───────────────────────────────────── User Tasks: | Search | Add to | Contact | | Browse | Cart | Support | | Compare | Checkout | Return | | | Pay | Review | ───────────────────────────────────── Release 1: | Basic | Cart + | Email | (MVP) | search | Checkout | form | ───────────────────────────────────── Release 2: | Filters | Saved | Live | | Sort | cards | chat | | Compare | Wishlist | FAQ | ───────────────────────────────────── Release 3: | AI search | Subscr. | Chatbot | | Reco's | Gift cards | Ticket |
Story Map Template
## Story Map: [Product/Feature Name] ### Backbone (Activities - user's high-level goals) 1. [Activity 1]: [description] 2. [Activity 2]: [description] 3. [Activity 3]: [description] ### Walking Skeleton (minimum viable flow) | Activity | Minimum Story | Priority | |----------|--------------|----------| | [Act 1] | [simplest version] | Must | | [Act 2] | [simplest version] | Must | | [Act 3] | [simplest version] | Must | ### Release Slices | Release | Scope | Theme | |---------|-------|-------| | R1 (MVP) | Walking skeleton | "It works" | | R2 | Enhanced UX | "It's pleasant" | | R3 | Advanced features | "It's powerful" |
Epic Decomposition
Epic to Stories Workflow
EPIC: User Authentication System ├── STORY: Email/password registration ├── STORY: Email verification ├── STORY: Login with email/password ├── STORY: Password reset via email ├── STORY: Social login (Google) ├── STORY: Social login (GitHub) ├── STORY: MFA setup (TOTP) ├── STORY: MFA verification on login ├── STORY: Session management (logout, expire) └── STORY: Account deletion
Decomposition Strategies
| Strategy | When to Use | Example |
|---|---|---|
| By workflow step | Sequential processes | Checkout: cart -> address -> payment -> confirmation |
| By data variation | Multiple input types | Import: CSV upload, API sync, manual entry |
| By user role | Multi-role features | Dashboard: admin view, manager view, user view |
| By CRUD operation | Data management | Products: create, read, update, delete |
| By business rule | Complex logic | Pricing: base price, discounts, tax, shipping |
| By platform | Multi-platform | Notifications: email, push, SMS, in-app |
| By performance | Optimization layers | Search: basic search, filters, autocomplete, facets |
Decomposition Template
## Epic: [Epic Name] **Business Value:** [neden onemli] **Target Persona:** [kim icin] **Size Estimate:** [S/M/L/XL] ### Stories | # | Story | Priority | Size | Sprint | |---|-------|----------|------|--------| | 1 | As a [role], I want [X], so that [Y] | Must | S | 1 | | 2 | As a [role], I want [X], so that [Y] | Must | M | 1 | | 3 | As a [role], I want [X], so that [Y] | Should | S | 2 | | 4 | As a [role], I want [X], so that [Y] | Could | M | 3 | ### Dependencies - Story 2 depends on Story 1 - Story 4 can be done in parallel with Story 3 ### Definition of Done (Epic Level) - [ ] All Must stories completed - [ ] Integration tests passing - [ ] Documentation updated - [ ] Stakeholder demo completed
Decomposition Anti-Patterns
| Anti-Pattern | Neden Yanlis | Dogru Yol |
|---|---|---|
| Technical decomposition | "Create DB schema" has no user value | Split by user-facing behavior |
| Too small (< 1 hour) | Overhead > value | Combine related micro-tasks |
| Too large (> 1 sprint) | Unestimable, risky | Decompose further |
| Horizontal slicing | "Build all APIs, then all UI" | Vertical slice (API + UI for one feature) |
Edge Case Stories
Common Edge Cases
## Edge Case Stories for [Feature] ### Empty State As a new user, When I have no [items/data/history], I want to see a helpful empty state with a clear CTA, so that I know how to get started. ### Error Recovery As a user, When an operation fails (network error, timeout, server error), I want to see a clear error message with a retry option, so that I can recover without losing my work. ### Boundary Values As a user, When I enter the maximum allowed value (e.g., 10,000 characters in a text field), I want to see a character counter and graceful truncation, so that I know my limits before submitting. ### Concurrent Access As a user, When another user edits the same resource simultaneously, I want to be notified of the conflict, so that I don't accidentally overwrite their changes. ### Offline / Slow Connection As a mobile user, When I lose network connectivity, I want my pending actions to be queued and synced when back online, so that I don't lose my work. ### Permission Denied As a user without admin privileges, When I try to access an admin-only feature, I want to see a clear message explaining why access is denied, so that I can request access if needed. ### Data Migration As an existing user, When the system migrates to a new version, I want my existing data to be preserved and correctly mapped, so that I don't lose any information.
Edge Case Discovery Checklist
- What if the input is empty?
- What if the input is at maximum length?
- What if the input contains special characters / unicode?
- What if the user double-clicks / double-submits?
- What if the network fails mid-operation?
- What if the user has no permission?
- What if the data doesn't exist (404)?
- What if there are concurrent modifications?
- What if the browser is resized / mobile view?
- What if the user navigates away mid-process?
- What if the session expires during an action?
- What if the third-party service is down?
Non-Functional Requirement Stories
Performance
As a user, I want the dashboard to load within 2 seconds, so that I can quickly access my data without frustration. Acceptance Criteria: - Given normal network conditions (4G+) - When the user navigates to the dashboard - Then the page is fully interactive within 2 seconds - And the Largest Contentful Paint (LCP) is < 2.5s - And the First Input Delay (FID) is < 100ms
Security
As a security-conscious user, I want my session to expire after 30 minutes of inactivity, so that my account is protected if I forget to log out. Acceptance Criteria: - Given the user has been inactive for 30 minutes - When the user tries to perform an action - Then the user is redirected to the login page - And a "Session expired" message is shown - And no sensitive data remains in the browser
Accessibility
As a user with visual impairment, I want all form fields to have proper labels and error announcements, so that I can use the application with a screen reader. Acceptance Criteria: - Given all form fields have associated labels (aria-label or <label>) - When a validation error occurs - Then the error is announced by the screen reader (aria-live) - And focus moves to the first invalid field - And color is not the only indicator of error state
Scalability
As a system, I need to handle 10,000 concurrent users without degradation, so that the service remains reliable during peak usage. Acceptance Criteria: - Given 10,000 concurrent users - When performing standard operations - Then response time remains < 500ms (p95) - And error rate stays < 0.1% - And CPU usage stays < 80%
Reliability
As a user, I want my data changes to be saved even if the server crashes, so that I never lose my work. Acceptance Criteria: - Given the user submits a form - When the server acknowledges the request - Then the data is persisted to durable storage - And a power failure does not result in data loss - And transactions are ACID-compliant
Story Quality Checklist
Before Sprint Planning
- Story follows "As a... I want... so that..." format
- INVEST criteria all met
- Acceptance criteria written in Given-When-Then
- Happy path + at least 2 error scenarios covered
- Size is estimable (team agrees on story points)
- No technical jargon (understandable by non-devs)
- Dependencies identified and resolved
- Design/wireframe attached if UI story
- Edge cases identified
- NFR implications noted
Common Story Smells
| Smell | Symptom | Fix |
|---|---|---|
| Too vague | "As a user, I want a better experience" | Be specific about what "better" means |
| Too technical | "As a developer, I want to refactor the DB" | Reframe as user value |
| Too large | Team can't estimate confidently | Decompose into smaller stories |
| No value | "Create config file" | Attach to a user-facing story |
| Hidden dependency | "Requires API not built yet" | Make dependency explicit, plan accordingly |
| Gold plating | 15 acceptance criteria | Split into multiple stories |