plan-mode

name	plan_mode
description	Structured decomposition skill for complex development tasks. Outputs step-by-step plans before execution.

Plan Mode — Structured Task Decomposition

Trigger conditions (any one):

1. Involves collaboration across 2+ modules
2. Requires modifying 3+ files
3. User explicitly requests "plan first / plan / decompose task"

Skip conditions: Single-file simple modifications, user says "just do it", pure Q&A.

---

1 Plan Output Format

## Execution Plan

**Task**: [One-sentence description]
**Involved modules**: [Module list]
**Estimated files to modify**: [N]
**Rules/skills to load**: [List]

### Step Decomposition

| # | Action | Target file/location | Dependency | Checkpoint |
|---|--------|---------------------|-----------|------------|
| 1 | ... | ... | None | ... |

### Risks

### Completion Criteria

---

2 High-Frequency Task Templates

2.1 New Page Route

## Execution Plan

**Task**: New page route at [path]
**Involved modules**: app/ + components/ + lib/
**Estimated files to modify**: 2-5
**Rules/skills to load**: project_rule + code_review + proactive-correction

### Step Decomposition

| # | Action | Target file/location | Dependency | Checkpoint |
|---|--------|---------------------|-----------|------------|
| 1 | Create page directory under `app/` | `app/[segment]/page.tsx` | None | Directory structure correct |
| 2 | Implement page as Server Component with data fetching | `app/[segment]/page.tsx` | None | Async data fetch returns expected shape |
| 3 | Create reusable components if needed | `components/[Name].tsx` | None | Client Components only if interactive |
| 4 | Add `loading.tsx` if data fetch is slow | `app/[segment]/loading.tsx` | Step 2 | Suspense boundary wraps content |
| 5 | Add `error.tsx` for error handling | `app/[segment]/error.tsx` | Step 2 | Error boundary catches fetch errors |
| 6 | Add metadata export or `generateMetadata()` | `app/[segment]/page.tsx` | Step 2 | SEO metadata present |

### Risks
- Server/Client boundary violations (using hooks in Server Components)
- Missing error/loading states for async operations

### Completion Criteria
- Page renders correctly at the expected URL
- No `'use client'` on layout.tsx
- loading.tsx and error.tsx present for async routes
- Metadata API used for SEO

2.2 New API Route

## Execution Plan

**Task**: New API route handler
**Involved modules**: app/api/
**Estimated files to modify**: 1-3
**Rules/skills to load**: project_rule + code_review

### Step Decomposition

| # | Action | Target file/location | Dependency | Checkpoint |
|---|--------|---------------------|-----------|------------|
| 1 | Create route directory under `app/api/` | `app/api/[segment]/route.ts` | None | Directory structure correct |
| 2 | Implement HTTP method handlers | `app/api/[segment]/route.ts` | Step 1 | Each handler returns `NextResponse` |
| 3 | Add input validation (zod) | `app/api/[segment]/route.ts` | Step 2 | Invalid input returns 400 |
| 4 | Add error handling with proper status codes | `app/api/[segment]/route.ts` | Step 2 | Errors return structured JSON |

### Risks
- Hardcoded API base URLs in client code
- Missing input validation on POST/PUT
- Leaking server-only secrets in responses

### Completion Criteria
- All HTTP methods return proper `NextResponse.json()`
- Input validation present for write operations
- Error responses include meaningful status codes

2.3 New Shared Component

## Execution Plan

**Task**: New shared UI component
**Involved modules**: components/ + lib/
**Estimated files to modify**: 1-3
**Rules/skills to load**: project_rule + code_review

### Step Decomposition

| # | Action | Target file/location | Dependency | Checkpoint |
|---|--------|---------------------|-----------|------------|
| 1 | Create component file | `components/[Name].tsx` | None | PascalCase naming |
| 2 | Add `'use client'` only if interactive | `components/[Name].tsx` | Step 1 | Directive only if needed |
| 3 | Define TypeScript props interface | `components/[Name].tsx` | Step 1 | Props fully typed (no `any`) |
| 4 | Add styles (Tailwind or CSS Module) | Component file | Step 1 | Styles are scoped |
| 5 | Export component | `components/[Name].tsx` | Steps 1-3 | Default or barrel export |

### Risks
- Unnecessary `'use client'` increasing client bundle
- Missing TypeScript types for props

### Completion Criteria
- Component renders correctly in isolation
- `'use client'` only present if needed
- Props are fully typed

2.4 Add Server Action (Data Mutation)

## Execution Plan

**Task**: Add Server Action for data mutation
**Involved modules**: app/ + lib/ + components/
**Estimated files to modify**: 2-4
**Rules/skills to load**: project_rule + code_review

### Step Decomposition

| # | Action | Target file/location | Dependency | Checkpoint |
|---|--------|---------------------|-----------|------------|
| 1 | Create Server Action | `lib/actions/[name].ts` | None | File starts with `'use server'` |
| 2 | Implement action with input validation | `lib/actions/[name].ts` | Step 1 | Zod schema validates input |
| 3 | Add `revalidatePath` after mutation | `lib/actions/[name].ts` | Step 2 | Cache revalidation present |
| 4 | Wire action to form/component | `components/[Form].tsx` | Step 3 | Form calls action via `action` prop |

### Risks
- Missing revalidation after mutation (stale data)
- No error handling in Server Action

### Completion Criteria
- Mutation persists data correctly
- UI updates reflect the mutation without full page reload
- Error states are handled and displayed

---

3 Execution Principles

1. Output plan first, wait for user confirmation (unless user says "just do it")
2. Strict sequential execution when steps have dependencies, parallel when independent
3. Verify checkpoint after each step; stop and explain if not passed
4. Correction checkpoint after each step — delegate proactive-correction agent for dimension 2 scan
5. Pause and ask when encountering gray areas
6. Plan is iterative: Update plan and notify user when new situations arise
7. Correction closure: After all steps, trigger proactive-correction for dimension 2+3 scan

---

4 Collaboration with Other Rules/Skills

Task Scenario	Additional Rules to Load
New page	project_rule + proactive-correction
New API route	project_rule + proactive-correction
New Server Action	project_rule + proactive-correction
Post-code generation	Auto-trigger code_review
Performance optimization	project_rule + code_review + proactive-correction