feature

Feature Creation Skill

When to Use

Add a feature when the user wants to:

• Add new functionality to an existing PRD
• Break down a large capability into trackable tasks
• Document implementation details for a specific feature

Workflow

Step 1: Identify Target PRD

Ask the user which PRD to add the feature to, or detect from context.

List existing PRDs:

ls docs/prd/

Step 2: Understand the Feature

Work with the user to define:

• What: What does this feature do?
• Why: Why is it needed?
• Acceptance criteria: How do we know it's done?
• Tasks: What implementation steps are required?

Step 3: Create Feature File

Use the template at templates/feature-template.md.

Save to: docs/prd/{prd-id}/features/{feature-id}.md

YAML Frontmatter:

---
id: feature-kebab-case-id
prd_id: parent-prd-id
number: N  # Next number after existing features (check docs/prd/{prd-id}/features/)
title: Feature Title
status: defined
created: YYYY-MM-DD
updated: YYYY-MM-DD
---

Feature Numbering: The number field determines task ID prefixes (task-{number}-{n}) and feature ordering. Check existing features in the PRD to find the next available number.

Step 4: Define Tasks

Critical: Use this exact format for task extraction:

## Tasks

### 1. First task title
Description of what needs to be done.

**Files to modify/create:**
- `path/to/file1.ts`
- `path/to/file2.ts`

**Expected changes:**
- Change 1
- Change 2

### 2. Second task title
Description...

**Files to modify/create:**
- `path/to/file.ts`

Each ### N. Title becomes a trackable task with:

• Test commit tracking (test: prefix)
• Implementation commit tracking (feat: prefix)
• Refactor commit tracking (refactor: prefix)

Task Granularity Guidance:

• Tasks should be granular enough to be independently testable
• Related tasks that are naturally implemented together CAN be grouped in a single commit
• Each task needs its own Task: header in the commit message for tracking
• Multiple Task: headers in one commit will all be tracked with the same commit SHA

Example multi-task commit:

feat(dashboard): add hooks display components

PRD: dashboard-hooks-display
Feature: hooks-display-ui
Task: Add hooks state to RepoDetailPage
Task: Add Hooks tab to repo header
Task: Create HooksList component

Implements hooks list and selection...

Step 5: Identify and Document Test Plan

IMPORTANT: Before implementation, analyze the codebase to identify relevant tests.

5a: Identify Relevant Tests

1. Find existing tests for affected code:

   • Look for test files adjacent to source files being modified
   • Check __tests__/ directories
   • Search for tests that import affected modules

2. Read the test files to understand:

   • Which test cases exercise the code paths you'll modify
   • Which assertions may need to change
   • What new scenarios need test coverage

3. Categorize each test:

   • Regression: Tests that should continue to pass unchanged
   • Amended: Tests whose expectations need updating
   • New: Tests that need to be written

5b: Document in Feature File

Add a Test Plan section using emoji categories:

Emoji	Category	Description
🔒	Regression	Must pass unchanged
✏️	Amended Case	Existing case to be modified
🆕	New Case	New test case in existing file
📄	New File	Entirely new test file

## Test Plan

### 🔒 Regression Tests
| File | Cases | Status |
|------|-------|--------|
| src/__tests__/existing.test.ts | all existing | ❌ |

### 🆕 New Tests
| File | Case | Status |
|------|------|--------|
| src/__tests__/feature.test.ts | handles new feature | ❌ |

Step 6: Update Parent PRD

Add a reference to the new feature in docs/prd/{prd-id}/prd.md:

### Feature N: {Feature Title}
**File**: [features/{feature-id}.md](features/{feature-id}.md)
**Status**: defined
**Description**: Brief description of what this feature does

Step 7: Sync Progress

After creating the feature file, call:

plan sync

This updates progress.json with the new feature and tasks.

Step 8: Confirm Creation

Tell the user:

"I've added feature '{title}' to PRD '{prd-id}' with {N} tasks."

Quality Checklist

• Feature ID is unique within the PRD
• prd_id matches parent PRD exactly
• Acceptance criteria are testable (use checkboxes)
• Tasks use ### N. Task Name format (numbered)
• Each task has files to modify listed
• Test plan identifies regression/amended/new tests
• Feature is linked from parent PRD

Template

• Feature: templates/feature-template.md

Example

User: "Add a quality CLI command to the code-quality PRD"

Claude:
1. Confirm PRD: "Adding to code-quality-analysis PRD?"
2. Discuss: "What subcommands? What options?"
3. Create:
   - docs/prd/code-quality-analysis/features/quality-cli-command.md
4. Update:
   - docs/prd/code-quality-analysis/prd.md (add feature reference)
5. Call `plan sync`
6. Confirm: "Added 'Quality CLI Command' with 5 tasks"