pr-message-writer

PR Message Writer

Write comprehensive, well-structured pull request descriptions by analyzing code changes and following established best practices for technical documentation.

Workflow

Step 1: Gather Context

1. Determine the main branch:

   git symbolic-ref refs/remotes/origin/HEAD | sed 's@^refs/remotes/origin/@@'
   

   Falls back to main or master if not set.

2. Find the merge base:

   MAIN_BRANCH=$(git symbolic-ref refs/remotes/origin/HEAD 2>/dev/null | sed 's@^refs/remotes/origin/@@' || echo "main")
   MERGE_BASE=$(git merge-base HEAD origin/$MAIN_BRANCH)
   

3. Collect all changes since the branch diverged:

   git log --oneline $MERGE_BASE..HEAD
   git diff --stat $MERGE_BASE..HEAD
   git diff $MERGE_BASE..HEAD
   

4. If a ticket ID or branch name is provided as an argument, include it in the PR title.

5. Gather ticket context. The ticket content is essential for writing accurate testing instructions and understanding the business requirement. If the ticket content is available in context (e.g., from a previous conversation or your project tracker), use it. If it is NOT available or has fallen out of context, ask the user to provide the ticket content before proceeding. Do not guess or invent requirements.

Step 2: Analyze Changes

Read every changed file and understand:

• What was changed (new files, modified logic, deleted code)
• Why the change was made (bug fix, new feature, refactoring, performance)
• Impact on existing functionality (breaking changes, migrations, cache invalidation)
• Dependencies introduced or removed

Step 3: Follow the Template

Use the PR message template for structure: template

Review real-world examples for tone and detail level: examples

Step 4: Match Change Type to Categories

Apply the appropriate sections based on what the PR touches:

Category	When to Include
Database and Entity/Model Changes	New tables, columns, migrations, schema changes
API Changes (REST/GraphQL)	New or modified endpoints, query/mutation changes
Admin Interface Changes	New admin pages, filters, list views, form fields
Caching and Performance	Cache keys, invalidation, query optimization
Security and Permissions	Auth rules, role checks, access control changes
Event Handling	New events, handlers, message queue changes
Testing	New or modified test cases, fixtures, test utilities

Step 5: Write Testing Instructions (Optional)

Before writing testing scenarios, ask the user whether they want testing scenarios included in this PR message. Testing scenarios are optional. If the user declines, skip this step entirely and omit the "Test scenarios" section from the PR message. Still include the "Testing instructions" section with basic verification steps and database queries if applicable.

If the user wants testing scenarios included:

Target audience: QA testers with ZERO codebase knowledge. They do not know about internal code structure, classes, services, or any implementation details. Write every instruction as if explaining to someone who has never seen the code and never will.

Rules for testing instructions:

• NEVER reference code - no file paths, class names, method names, variable names, or internal architecture
• NEVER use technical implementation terms - no internal framework concepts, no code-level abstractions
• If UI exists, provide exact click-by-click navigation: which URL to open, which button to click, which field to fill, what value to enter, what to expect on screen
• If no UI exists (API-only or GraphQL-only), provide the exact request to execute - full query/mutation with example variables, which tool to use (GraphQL playground, Postman, curl), and the exact URL/endpoint
• Database queries are OK - QA knows how to run SQL. Include queries when there is no other way to verify something through UI or API
• Every scenario is checkboxed - use - [ ] **Scenario N: Name** so QA can tick them off
• Every scenario ends with "Expected results" - a bullet list of what should be visible/changed after the steps
• Every scenario is step-by-step - numbered steps, one action per step
• Use plain language - "Go to the admin panel", "Click the 'Users' menu item", "You should see a green success message"

Finding real URLs and UI paths

When a scenario involves navigating to a page, search the codebase for the actual route/URL rather than guessing or using placeholder URLs. Look in:

• Route configuration files (e.g., route definitions, annotations, attributes, decorators)
• Controller or handler definitions with route mappings
• Frontend router definitions (e.g., client-side router configs, page-based routing)

Always provide the real relative URL path (e.g., /en/account/internal-store) rather than generic placeholders like https://your-staging.example.com/store. If the route has dynamic segments, show the pattern and explain what to substitute (e.g., /en/account/store/checkout/{packageId} - replace {packageId} with the ID from the previous step).

When a feature is reachable through the UI, lead with the UI navigation - describe how to get there by clicking through menus and buttons. Only fall back to direct URL navigation when there is no UI path or the UI path is too many clicks deep.

Providing test data

Always provide concrete, realistic test data that QA can copy-paste directly. Never say "enter a valid credit card" or "use test credentials" without giving the actual values.

Common test data to include when relevant:

• Credit cards (Stripe test mode): 4242 4242 4242 4242 (Visa, succeeds), 4000 0000 0000 3220 (3D Secure required), 4000 0000 0000 0002 (declined). Expiry: any future date (e.g., 12/34). CVC: any 3 digits (e.g., 123)
• Credit cards (Adyen test mode): 4111 1111 1111 1111 (Visa), 5500 0000 0000 0004 (Mastercard). Expiry: 03/30. CVC: 737
• PayPal sandbox: provide sandbox buyer email/password if available, or note "use PayPal sandbox credentials from the team"
• Email addresses: use realistic but clearly fake addresses (e.g., qa-tester+scenario1@example.com)
• Phone numbers: use test numbers for the relevant country (e.g., +1 555 0100 for US test)
• Dates: use specific dates, not "any date" (e.g., 2025-01-15)
• Amounts/quantities: use specific numbers that test the scenario (e.g., quantity 3, not "some items")

If the project uses a specific payment provider, search for its test mode configuration in the codebase (look for environment variable keys related to payment, payment config files) to determine which test card numbers apply.

When test data requires database setup (e.g., a specific user account, a product with certain stock), provide the exact SQL INSERT or describe the UI steps to create it.

For every PR, include:

• Step-by-step verification - exact UI navigation or exact API requests to run
• Copy-pasteable requests - full GraphQL queries/mutations or curl commands with example values, specifying where to run them
• Database verification - SQL queries to confirm data integrity (QA can run these)
• Edge cases - described as user actions and expected outcomes, not as code behavior

Step 6: Maintain Consistency

• Use the same section ordering as the template
• Write in imperative mood for descriptions ("Add product review entity" not "Added" or "Adds")
• Include code blocks with language hints for syntax highlighting
• Keep line length reasonable for readability in PR tools

Quality Checklist

Before finalizing the PR message, verify:

• Ticket content was referenced (or user was asked to provide it)
• Title is concise and includes ticket ID if available
• "What have I changed" covers every file group logically
• Testing instructions contain ZERO code references (no file names, class names, method names)
• Testing instructions are step-by-step with one action per step
• Every scenario specifies exact UI navigation OR exact API requests to run
• Every scenario has a checkbox (- [ ]) and an "Expected results" bullet list
• URLs in scenarios are real routes from the codebase (not placeholder URLs)
• Test data is concrete and copy-pasteable (card numbers, emails, dates - not "use a valid card")
• Testing instructions are understandable by someone with zero codebase knowledge
• Database verification queries are included for any schema changes
• Product-facing changes are called out explicitly
• No sensitive data (secrets, tokens, internal URLs) is included
• Migration steps are documented if applicable
• Breaking changes are highlighted prominently

Common Patterns by PR Type

New Feature

• Describe the business requirement briefly
• List new entities/models, endpoints, and admin pages
• Provide full testing flow from setup to verification
• Include database queries showing new data

Bug Fix

• State the bug clearly: what happened vs. what should happen
• Explain root cause
• Describe the fix and why this approach was chosen
• Include regression test instructions

Refactoring

• Explain motivation (tech debt, performance, maintainability)
• Confirm no behavioral changes (or document any intentional ones)
• List before/after comparisons if helpful
• Note any config or dependency changes

Database Migration

• List all schema changes (new tables, columns, indexes)
• Note if migration is reversible
• Flag any data migrations that touch existing rows
• Include rollback instructions if applicable

Reference Files

Reference	Contents
PR message template	Structured template for PR descriptions with all optional sections
Example PR messages	Real-world examples for features, bug fixes, and admin changes

Integration with Other Skills

Situation	Recommended Skill
Starting work on a ticket end-to-end	ticket-delivery
Generating a summary report after completing work	report-writer
Reviewing code before writing the PR	code-review-excellence
Requesting a code review from teammates	requesting-code-review