Brainstorm a Feature or Improvement

Interaction Rules

1. Ask one question at a time - Do not batch several unrelated questions into one message.
2. Prefer single-select multiple choice - Use single-select when choosing one direction, one priority, or one next step.
3. Use multi-select rarely and intentionally - Use it only for compatible sets such as goals, constraints, non-goals, or success criteria that can all coexist. If prioritization matters, follow up by asking which selected item is primary.
4. Use the platform's question tool when available - When asking the user a question, prefer the platform's blocking question tool if one exists (AskUserQuestion in Claude Code, request_user_input in Codex, ask_user in Gemini). Otherwise, present numbered options in chat and wait for the user's reply before proceeding.

Output Guidance

• Keep outputs concise - Prefer short sections, brief bullets, and only enough detail to support the next decision.
• Use repo-relative paths - When referencing files, use paths relative to the repo root (e.g., src/models/user.rb), never absolute paths. Absolute paths make documents non-portable across machines and teammates.

Feature Description

<feature_description> #$ARGUMENTS </feature_description>

If the feature description above is empty, ask the user: "What would you like to explore? Please describe the feature, problem, or improvement you're thinking about."

Do not proceed until you have a feature description from the user.

Execution Flow

Phase 0: Resume, Assess, and Route

0.1 Resume Existing Work When Appropriate

If the user references an existing brainstorm topic or document, or there is an obvious recent matching *-requirements.md file in docs/brainstorms/:

• Read the document
• Confirm with the user before resuming: "Found an existing requirements doc for [topic]. Should I continue from this, or start fresh?"
• If resuming, summarize the current state briefly, continue from its existing decisions and outstanding questions, and update the existing document instead of creating a duplicate

0.2 Assess Whether Brainstorming Is Needed

Clear requirements indicators:

• Specific acceptance criteria provided
• Referenced existing patterns to follow
• Described exact expected behavior
• Constrained, well-defined scope

If requirements are already clear: Keep the interaction brief. Confirm understanding and present concise next-step options rather than forcing a long brainstorm. Only write a short requirements document when a durable handoff to planning or later review would be valuable. Skip Phase 1.1 and 1.2 entirely — go straight to Phase 1.3 or Phase 3.

0.3 Assess Scope

Use the feature description plus a light repo scan to classify the work:

• Lightweight - small, well-bounded, low ambiguity
• Standard - normal feature or bounded refactor with some decisions to make
• Deep - cross-cutting, strategic, or highly ambiguous

If the scope is unclear, ask one targeted question to disambiguate and then proceed.

Phase 1: Understand the Idea

1.1 Existing Context Scan

Scan the repo before substantive brainstorming. Match depth to scope:

Lightweight — Search for the topic, check if something similar already exists, and move on.

Standard and Deep — Two passes:

Constraint Check — Check project instruction files (AGENTS.md, and CLAUDE.md only if retained as compatibility context) for workflow, product, or scope constraints that affect the brainstorm. If these add nothing, move on.

Topic Scan — Search for relevant terms. Read the most relevant existing artifact if one exists (brainstorm, plan, spec, skill, feature doc). Skim adjacent examples covering similar behavior.

If nothing obvious appears after a short scan, say so and continue. Two rules govern technical depth during the scan:

1. Verify before claiming — When the brainstorm touches checkable infrastructure (database tables, routes, config files, dependencies, model definitions), read the relevant source files to confirm what actually exists. Any claim that something is absent — a missing table, an endpoint that doesn't exist, a dependency not in the Gemfile, a config option with no current support — must be verified against the codebase first; if not verified, label it as an unverified assumption. This applies to every brainstorm regardless of topic.

2. Defer design decisions to planning — Implementation details like schemas, migration strategies, endpoint structure, or deployment topology belong in planning, not here — unless the brainstorm is itself about a technical or architectural decision, in which case those details are the subject of the brainstorm and should be explored.

1.2 Product Pressure Test

Before generating approaches, challenge the request to catch misframing. Match depth to scope:

Lightweight:

• Is this solving the real user problem?
• Are we duplicating something that already covers this?
• Is there a clearly better framing with near-zero extra cost?

Standard:

• Is this the right problem, or a proxy for a more important one?
• What user or business outcome actually matters here?
• What happens if we do nothing?
• Is there a nearby framing that creates more user value without more carrying cost? If so, what complexity does it add?
• Given the current project state, user goal, and constraints, what is the single highest-leverage move right now: the request as framed, a reframing, one adjacent addition, a simplification, or doing nothing?
• Favor moves that compound value, reduce future carrying cost, or make the product meaningfully more useful or compelling
• Use the result to sharpen the conversation, not to bulldoze the user's intent

Deep — Standard questions plus:

• What durable capability should this create in 6-12 months?
• Does this move the product toward that, or is it only a local patch?

1.3 Collaborative Dialogue

Use the platform's blocking question tool when available (see Interaction Rules). Otherwise, present numbered options in chat and wait for the user's reply before proceeding.

Guidelines:

• Ask questions one at a time
• Prefer multiple choice when natural options exist
• Prefer single-select when choosing one direction, one priority, or one next step
• Use multi-select only for compatible sets that can all coexist; if prioritization matters, ask which selected item is primary
• Start broad (problem, users, value) then narrow (constraints, exclusions, edge cases)
• Clarify the problem frame, validate assumptions, and ask about success criteria
• Make requirements concrete enough that planning will not need to invent behavior
• Surface dependencies or prerequisites only when they materially affect scope
• Resolve product decisions here; leave technical implementation choices for planning
• Bring ideas, alternatives, and challenges instead of only interviewing

Exit condition: Continue until the idea is clear OR the user explicitly wants to proceed.

Phase 2: Explore Approaches

If multiple plausible directions remain, propose 2-3 concrete approaches based on research and conversation. Otherwise state the recommended direction directly.

When useful, include one deliberately higher-upside alternative:

• Identify what adjacent addition or reframing would most increase usefulness, compounding value, or durability without disproportionate carrying cost. Present it as a challenger option alongside the baseline, not as the default. Omit it when the work is already obviously over-scoped or the baseline request is clearly the right move.

For each approach, provide:

• Brief description (2-3 sentences)
• Pros and cons
• Key risks or unknowns
• When it's best suited

Lead with your recommendation and explain why. Prefer simpler solutions when added complexity creates real carrying cost, but do not reject low-cost, high-value polish just because it is not strictly necessary.

If one approach is clearly best and alternatives are not meaningful, skip the menu and state the recommendation directly.

If relevant, call out whether the choice is:

• Reuse an existing pattern
• Extend an existing capability
• Build something net new

Phase 3: Capture the Requirements

Write or update a requirements document only when the conversation produced durable decisions worth preserving.

This document should behave like a lightweight PRD without PRD ceremony. Include what planning needs to execute well, and skip sections that add no value for the scope.

The requirements document is for product definition and scope control. Do not include implementation details such as libraries, schemas, endpoints, file layouts, or code structure unless the brainstorm is inherently technical and those details are themselves the subject of the decision.

Required content for non-trivial work:

• Problem frame
• Concrete requirements or intended behavior with stable IDs
• Scope boundaries
• Success criteria

Include when materially useful:

• Key decisions and rationale
• Dependencies or assumptions
• Outstanding questions
• Alternatives considered
• High-level technical direction only when the work is inherently technical and the direction is part of the product/architecture decision

Document structure: Use this template and omit clearly inapplicable optional sections:

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