Brainstorming

---
name: brainstorming
description: Use before any creative or feature work - creating features, building components, adding functionality, or modifying behavior. Explores user intent, requirements, and design through dialogue before any implementation begins. When the design is settled, consider writing-plans next.
---

# Brainstorming Ideas Into Designs

Turn ideas into fully formed designs and specs through natural collaborative dialogue. Understand the current project context, ask batched clarifying questions to refine the idea, then present the design and get user approval.

<HARD-GATE>
Do NOT write any code, scaffold any project, or take any implementation action until you have presented a design and the user has approved it. This applies to EVERY project regardless of perceived simplicity.
</HARD-GATE>

## Anti-Pattern: "This Is Too Simple To Need A Design"

Every project goes through this process. A todo list, a single-function utility, a config change — all of them. "Simple" projects are where unexamined assumptions cause the most wasted work. The design can be short (a few sentences for truly simple projects), but you MUST present it and get approval.

## Checklist

Create a task for each of these items and complete them in order:

1. **Explore project context** — check files, docs, recent commits
2. **Ask clarifying questions** — batched via AskUserQuestion; understand purpose, constraints, success criteria
3. **Propose 2-3 approaches** — with trade-offs and your recommendation; apply YAGNI ruthlessly, removing unnecessary features from each
4. **Present design** — in sections scaled to their complexity, get a single design approval after the full design is presented
5. **Write design doc** — save the spec (e.g. `docs/specs/YYYY-MM-DD-<topic>-design.md`) and commit it
6. **Spec self-review** — quick inline check for placeholders, contradictions, ambiguity, scope
7. **User reviews written spec** — ask the user to review the spec file before proceeding
8. **Transition to implementation planning** — the next step is a detailed implementation plan (see the writing-plans skill), not code

**The terminal state of brainstorming is starting the implementation plan.** Never jump from an approved design straight into writing code.

## The Process

**Understanding the idea:**

- Check the current project state first (files, docs, recent commits)
- Before asking detailed questions, assess scope: if the request describes multiple independent subsystems (e.g., "build a platform with chat, file storage, billing, and analytics"), flag this immediately. Don't spend questions refining details of a project that needs to be decomposed first.
- If the project is too large for a single spec, help the user decompose into sub-projects: what are the independent pieces, how do they relate, what order should they be built? Then brainstorm the first sub-project through the normal design flow. Each sub-project gets its own spec, plan, and implementation cycle.
- For appropriately-scoped projects, ask batched clarifying questions to refine the idea
- Prefer multiple choice questions when possible, but open-ended is fine too
- Batch related questions with AskUserQuestion: up to 4 per round, one topic per question, options with the recommended choice first; ask one question per message only when that tool is unavailable.
- Focus on understanding: purpose, constraints, success criteria
- If the design has two or more components with disjoint file ownership, record them as lane candidates for parallel-plans; the plan decides whether to fan out.

**Exploring approaches:**

- Propose 2-3 different approaches with trade-offs
- Present options conversationally with your recommendation and reasoning
- Lead with your recommended option and explain why

**Presenting the design:**

- Once you believe you understand what you're building, present the design
- Scale each section to its complexity: a few sentences if straightforward, up to 200-300 words if nuanced
- Present the full design, then get a single approval — not after each section
- Cover: architecture, components, data flow, error handling, testing
- Be ready to go back and clarify if something doesn't make sense

**Design for isolation and clarity:**

- Break the system into smaller units that each have one clear purpose, communicate through well-defined interfaces, and can be understood and tested independently
- For each unit, you should be able to answer: what does it do, how do you use it, and what does it depend on?
- Can someone understand what a unit does without reading its internals? Can you change the internals without breaking consumers? If not, the boundaries need work.
- Smaller, well-bounded units are also easier to work with — reasoning is more reliable about code you can hold in context at once. When a file grows large, that's often a signal it's doing too much.

**Working in existing codebases:**

- Explore the current structure before proposing changes. Follow existing patterns.
- Where existing code has problems that affect the work (a file that's grown too large, unclear boundaries, tangled responsibilities), include targeted improvements as part of the design — the way a good developer improves code they're working in.
- Don't propose unrelated refactoring. Stay focused on what serves the current goal.

## After the Design

**Documentation:**

- Write the validated design (spec) to a dated file, e.g. `docs/specs/YYYY-MM-DD-<topic>-design.md` (user preferences for spec location override this default)
- Commit the design document to git

**Spec Self-Review** — after writing the spec, look at it with fresh eyes:

1. **Placeholder scan:** Any "TBD", "TODO", incomplete sections, or vague requirements? Fix them.
2. **Internal consistency:** Do any sections contradict each other? Does the architecture match the feature descriptions?
3. **Scope check:** Is this focused enough for a single implementation plan, or does it need decomposition?
4. **Ambiguity check:** Could any requirement be interpreted two different ways? If so, pick one and make it explicit.

Fix any issues inline. No need to re-review — just fix and move on.

**User Review Gate** — after the self-review passes, ask the user to review the written spec:

> "Spec written and committed to `<path>`. Please review it and let me know if you want to make any changes before we start writing out the implementation plan."

Wait for the user's response. If they request changes, make them and re-run the self-review. Only proceed once the user approves.

**Implementation:**

- Create a detailed implementation plan from the approved spec (the writing-plans skill covers this)
- Do not start coding directly from the spec