brainstorming

Brainstorming

This skill provides detailed process knowledge for effective brainstorming sessions that clarify WHAT to build before diving into HOW to build it.

When to Use This Skill

Brainstorming is valuable when:

• Requirements are unclear or ambiguous
• Multiple approaches could solve the problem
• Trade-offs need to be explored with the user
• The user hasn't fully articulated what they want
• The feature scope needs refinement

Brainstorming can be skipped when:

• Requirements are explicit and detailed
• The user knows exactly what they want
• The task is a straightforward bug fix or well-defined change

Core Process

Phase 0: Assess Requirement Clarity

Before diving into questions, assess whether brainstorming is needed.

Signals that requirements are clear:

• User provided specific acceptance criteria
• User referenced existing patterns to follow
• User described exact behavior expected
• Scope is constrained and well-defined

Signals that brainstorming is needed:

• User used vague terms ("make it better", "add something like")
• Multiple reasonable interpretations exist
• Trade-offs haven't been discussed
• User seems unsure about the approach

If requirements are clear, suggest: "Your requirements seem clear. Consider proceeding directly to planning or implementation."

Phase 1: Understand the Idea

Ask questions one at a time to understand the user's intent. Avoid overwhelming with multiple questions.

Question Techniques:

1. Prefer multiple choice when natural options exist

   • Good: "Should the notification be: (a) email only, (b) in-app only, or (c) both?"
   • Avoid: "How should users be notified?"

2. Start broad, then narrow

   • First: What is the core purpose?
   • Then: Who are the users?
   • Finally: What constraints exist?

3. Validate assumptions explicitly

   • "I'm assuming users will be logged in. Is that correct?"

4. Ask about success criteria early

   • "How will you know this feature is working well?"

Key Topics to Explore:

Topic	Example Questions
Purpose	What problem does this solve? What's the motivation?
Users	Who uses this? What's their context?
Constraints	Any technical limitations? Timeline? Dependencies?
Success	How will you measure success? What's the happy path?
Edge Cases	What shouldn't happen? Any error states to consider?
Existing Patterns	Are there similar features in the codebase to follow?

Exit Condition: Continue until the idea is clear OR user says "proceed" or "let's move on"

Phase 2: Explore Approaches

After understanding the idea, propose 2-3 concrete approaches.

Structure for Each Approach:

### Approach A: [Name]

[2-3 sentence description]

**Pros:**
- [Benefit 1]
- [Benefit 2]

**Cons:**
- [Drawback 1]
- [Drawback 2]

**Best when:** [Circumstances where this approach shines]

Guidelines:

• Lead with a recommendation and explain why
• Be honest about trade-offs
• Consider YAGNI—simpler is usually better
• Reference codebase patterns when relevant

Phase 3: Capture the Design

Summarize key decisions in a structured format.

Design Doc Structure:

---
date: YYYY-MM-DD
topic: <kebab-case-topic>
---

# <Topic Title>

## What We're Building
[Concise description—1-2 paragraphs max]

## Why This Approach
[Brief explanation of approaches considered and why this one was chosen]

## Key Decisions
- [Decision 1]: [Rationale]
- [Decision 2]: [Rationale]

## Open Questions
- [Any unresolved questions for the planning phase]

## Next Steps
→ `/gc:plan` for implementation details

Output Location: docs/brainstorms/YYYY-MM-DD-<topic>-brainstorm.md

Phase 4: Handoff

Present clear options for what to do next:

1. Proceed to planning → Run /gc:plan
2. Refine further → Continue exploring the design
3. Done for now → User will return later

YAGNI Principles

During brainstorming, actively resist complexity:

• Don't design for hypothetical future requirements
• Choose the simplest approach that solves the stated problem
• Prefer boring, proven patterns over clever solutions
• Ask "Do we really need this?" when complexity emerges
• Defer decisions that don't need to be made now

Incremental Validation

Keep sections short—200-300 words maximum. After each section of output, pause to validate understanding:

• "Does this match what you had in mind?"
• "Any adjustments before we continue?"
• "Is this the direction you want to go?"

This prevents wasted effort on misaligned designs.

Anti-Patterns to Avoid

Anti-Pattern	Better Approach
Asking 5 questions at once	Ask one at a time
Jumping to implementation details	Stay focused on WHAT, not HOW
Proposing overly complex solutions	Start simple, add complexity only if needed
Ignoring existing codebase patterns	Research what exists first
Making assumptions without validating	State assumptions explicitly and confirm
Creating lengthy design documents	Keep it concise—details go in the plan

Integration with Planning

Brainstorming answers WHAT to build:

• Requirements and acceptance criteria
• Chosen approach and rationale
• Key decisions and trade-offs

Planning answers HOW to build it:

• Implementation steps and file changes
• Technical details and code patterns
• Testing strategy and verification

When brainstorm output exists, /gc:plan should detect it and use it as input, skipping its own idea refinement phase.