---
name: plan-design
description: Use when creating or developing, before writing code or implementation plans - refines rough ideas into fully-formed designs through collaborative questioning, alternative exploration, and incremental validation. Don't use during clear 'mechanical' processes
---

# Idea to Design

## 1. Initial Setup (Mandatory)

- **Create Plan Immediately:** Before any dialogue, create `.claude/docs/plans/<topic>-design.md`.
- **Initial Content:** Problem statement, goals, and known requirements.
- **The Golden Rule:** Update this file **after every user response**. Do not wait until the end.

## 2. Discovery Phase

- **Context Check:** Review existing files, docs, and commits first.
- **Batch Questions:** Use the ask tool to group up to 4 related questions (purpose, constraints, success metrics).
- **Preference:** Use multiple-choice or multi-select options in the tool whenever possible.
- **Loop:** Question -> Answer -> Edit Plan -> Follow-up.

## 3. Design Exploration

- **Propose Alternatives:** Present 2–3 approaches with trade-offs.
- **Recommend:** Lead with a preferred option and explain the "Why."
- **Keep it Lean:** Apply **YAGNI** (You Ain't Gonna Need It) to prune scope.

## 4. Presentation & Validation

- **Chunking:** Present the design in 200–300 word sections (Architecture, Data Flow, etc.).
- **Incremental Approval:** Use `AskUserQuestion` after _each_ section to confirm alignment.
- **Scope:** High-level conceptual flow only (e.g., "Use React Query for state").

## 5. Strict Boundaries (Design vs. Implementation)

| In Scope (Design)                    | Out of Scope (Implementation)              |
| :----------------------------------- | :----------------------------------------- |
| High-level architecture & tech stack | Specific file paths & directory structures |
| Component responsibilities           | Numbered implementation phases/steps       |
| Data flow logic                      | Complete code snippets or Git commands     |
| Trade-offs & assumptions             | "Files to create/modify" lists             |

> **CAUTION:** If you start writing "Phase 1: Setup" or specific file paths, **STOP**. Transition to the plan-write skill instead.

## 6. Closing

- **Final Review:** Ensure the `.claude/docs/plans/` file is polished and complete.
- **Next Step:** Ask: "Ready to set up for implementation?"
  - **If Yes:** Transition to `plan-write`.