majiayu000 User Story Writer Skill
This skill produces production-ready user stories from a feature brief, PRD section, or verbal description. Each story follows the standard format with a clear who/what/why, behavioural acceptance criteria in Given/When/Then format, edge cases, and definition of done. Output is ready to paste into Jira, Linear, or your planning tool.
Required Inputs
Ask the user for these if not provided:
- Feature or change to break into stories — paste the brief, PRD section, or describe the feature
- User types / personas involved (e.g. admin, end user, guest, API consumer)
- Scope — are we writing one story or decomposing an epic into a full set of stories?
- Acceptance criteria format preference — Given/When/Then, bullet checklist, or both?
- Technical constraints or notes — anything the engineering team has flagged that should shape the stories
Output Structure
For each story:
Story: [Short title — verb + noun, e.g. "Filter search results by date range"]
Epic: [Parent epic name — e.g. "Advanced Search"] Story ID: [Jira/Linear ID — leave blank if not yet created] Priority: [P1 / P2 / P3] Story points: [Leave blank — for engineering to estimate]
User Story
As a [specific user type — not "user"], I want to [concrete action they want to take], So that [the outcome they achieve — business value, not feature description].
Example:
As an account manager, I want to filter my client list by last contact date, so that I can quickly identify clients I haven't spoken to in over 30 days and prioritise outreach.
Context
[1–3 sentences of context that aren't in the user story itself: when does this story matter, what triggers the need, how does it fit into a larger flow. This helps engineers understand why before they ask.]
Acceptance Criteria
Format: Given / When / Then
Each criterion tests one specific behaviour. Write one GWT per observable outcome — not one GWT for the whole feature.
AC1: [Short name for this criterion]
Given [starting state or context]
When [user action]
Then [observable system behaviour]
AC2: [Short name]
Given [...]
When [...]
Then [...]
AC3: [Short name]
Given [...]
When [...]
Then [...]
Edge Cases
[List scenarios that are non-obvious but must be handled. These become additional ACs or notes to engineering.]
- [Edge case 1]: [e.g. User applies a date filter that returns 0 results — show empty state with clear messaging and a "clear filters" action]
- [Edge case 2]: [e.g. User has >10,000 clients — filter must not degrade load time >200ms]
- [Edge case 3]: [e.g. Date filter persists across page refresh — or explicitly should not if that's the decision]
- [Permission edge case]: [e.g. Read-only users can see the filter but cannot save filter presets]
Out of Scope
[Explicitly state what this story does NOT cover — prevents scope creep and clarifies where the next story begins.]
- Saving and sharing filter presets (separate story — see [Story X])
- Bulk actions on filtered results
- Exporting filtered client list to CSV
Definition of Done
- Acceptance criteria all pass
- Edge cases handled (or explicitly deferred with a new ticket raised)
- Unit tests written for each AC
- Works on mobile viewport (if applicable)
- Accessibility: keyboard navigable and screen-reader compatible
- Error states are handled and copy approved
- Product and design have reviewed in staging
- No console errors in production build
Epic Decomposition Template
If the user provides an epic or feature brief, decompose it into a full set of stories before writing them:
Epic: [Name] Goal: [What outcome does completing this epic achieve?] Stories:
| # | Story | Notes | Dependencies |
|---|---|---|---|
| 1 | [Core happy path story — the simplest version of the feature that delivers value] | ||
| 2 | [Validation / error handling story] | Depends on #1 | |
| 3 | [Edge case or power user story] | Depends on #1 | |
| 4 | [Admin or configuration story] | ||
| 5 | [Performance or scale story — if applicable] | Depends on #1 |
Suggested sprint order: [Which stories are P1 for MVP? Which can follow in a later sprint?]
Common Story Anti-Patterns — and Fixes
Use these to review stories before handing to engineering:
| Anti-pattern | Example | Fix |
|---|---|---|
| Solution in the story | "As a user I want a dropdown filter" | Remove the UI decision — "As a user I want to filter by date range" |
| Vague "so that" | "so that it's easier to use" | Make it specific — "so that I can prioritise outreach without opening each record manually" |
| Too big | Story covers 5 distinct user flows | Split into separate stories per flow |
| No acceptance criteria | Story has description only | Add at least 3 GWT criteria before engineering starts |
| ACs that test the solution, not the behaviour | "Given the dropdown is open, When I select an option" | Test the outcome — "Given I have applied a date filter, When I view my results, Then only clients last contacted in that date range appear" |
| Missing empty state | No AC for what happens with 0 results | Add it — empty states are part of the feature |
| Missing error state | No AC for network failure or invalid input | Add error handling ACs explicitly |
Example: Full Story Set for a Feature
Feature brief: "Allow users to export their invoice history as a PDF or CSV"
Story 1: Export invoice list as CSV
As a finance admin, I want to export my invoice history as a CSV file, so that I can import it into our accounting software without manual data entry.
AC1: Successful export
Given I am on the Invoices page with at least one invoice
When I click "Export" and select "CSV"
Then a CSV file is downloaded containing all visible invoices with columns: Invoice ID, Date, Amount, Status, Customer Name
AC2: Empty state
Given I am on the Invoices page with no invoices
When I click "Export"
Then the export button is disabled and a tooltip reads "No invoices to export"
AC3: Filtered export
Given I have applied a date filter showing invoices from Jan 2026 only
When I click "Export" and select "CSV"
Then the export contains only invoices from Jan 2026 — not all invoices
Edge cases:
- Export with >10,000 invoices — must complete in <30s or show a progress indicator
- Export triggered on mobile — downloads to device's default download location
Out of scope: PDF export (Story 2), scheduled exports (future epic)
Story 2: Export invoice list as PDF
As a finance admin, I want to export my invoice history as a formatted PDF, so that I can share a professional summary with our accountant.
[... ACs follow same pattern ...]
Quality Checks
- Every story has a specific user type — not "a user" or "the system"
- The "so that" explains business value — not just feature description
- Each AC tests one observable outcome — not a bundle of behaviours
- Empty states, error states, and edge cases are explicitly handled
- Out of scope is documented — not assumed
- Stories are independent — they can be shipped individually without depending on unreleased work (except where explicitly noted)
Example Trigger Phrases
- "Write user stories for [feature] from this brief"
- "Break this PRD section into user stories with acceptance criteria"
- "Convert these feature requirements into Jira tickets"
- "Write the user stories and ACs for [feature name]"
- "Decompose this epic into individual stories ready for sprint planning"