What it does. You MUST use this before any creative work - creating features, building components, adding functionality, or modifying behavior. Explores user intent, requirements and design before implementation. Part of obra/superpowers (skills framework and dev methodology) (obra/superpowers).


Upstream	obra/superpowers
Skill file	skills/brainstorming/SKILL.md
License	MIT
Author	Jesse Vincent (obra)
Fetched	2026-09-10

Install

npx skills add obra/superpowers --skill brainstorming, or copy the skill folder into ~/.claude/skills/brainstorming/.
Raw file: curl -sL https://raw.githubusercontent.com/obra/superpowers/HEAD/skills/brainstorming/SKILL.md

SKILL.md (verbatim)

name: brainstorming
description: "You MUST use this before any creative work - creating features, building components, adding functionality, or modifying behavior. Explores user intent, requirements and design before implementation."

Brainstorming Ideas Into Designs

Help turn ideas into fully formed designs and specs through natural collaborative dialogue.

Start by classifying how much process the request needs, then work through your path: understand the context, refine the idea, present a design, and get your human partner's approval.

<HARD-GATE> Do NOT invoke any implementation skill, write any code, scaffold any project, or take any implementation action until you have told your human partner what you intend and they have approved it. This applies to EVERY task on EVERY path below — the ceremony scales with the task; the approval gate never does. </HARD-GATE>

Three Paths

Before your first question, classify the request and say the classification out loud — "this looks bounded, so I'll present a short design here rather than write a spec" — so your human partner can override it:

Spike — a feasibility question ("can we...", "is it possible...", "quick and dirty is fine") whose output is an answer, not code you keep. Present the question and what you'll try in 2-3 sentences, get a nod, then find out as cheaply as correctness allows. No design doc, no spec file. Report findings as a recommendation; anything you built stays labeled throwaway.
Bounded — a well-scoped change to code that already exists in this repo: a new flag, a small endpoint, a one-file fix. Understanding the kind of app is not enough — bounded means the flow you are changing is already here to read. If there is no existing flow to change, the task is not bounded. Ask the clarifying questions that matter, present a short design IN CHAT (a few sentences to a few short paragraphs), and STOP. Implementation starts only after your human partner says yes to that design — a bounded task's approval is as hard a gate as an architectural one. No spec file, no implementation plan document.
Architectural — new projects, new subsystems, changes that restructure how components fit together or alter interfaces others depend on. Follow the full process: questions, approaches, sectioned design, written spec, then the writing-plans skill.

When in doubt between two paths, take the heavier one. The ratchet is one-way: hidden complexity discovered mid-task upgrades the path — stop, say so, and step up. Nothing downgrades mid-task.

Anti-Pattern: "Too Simple To Need Approval"

Every path ends with your human partner approving your intent before implementation. A todo list, a single-function utility, a config change — the design may be two sentences in chat, but you MUST present it and get approval. "Simple" tasks are where unexamined assumptions cause the most wasted work. What scales with simplicity is the artifact, never the approval.

Red Flags

Thought	Reality
"This is too simple to need a design"	Simple means a short design, not no design. Two sentences in chat, then approval.
"I'll call it bounded and skip the spec"	Reaching for a label to skip work IS the doubt — take the heavier path.
"It's bounded and the design is obvious — I'll start while they read it"	The gate is the approval, not the design's length. Present, then stop until you hear yes.
"I understand this kind of app, so it's bounded"	Bounded measures the repo, not your familiarity. A new project has no existing flow — it is architectural.
"The spike works, so I'll keep the code"	A spike's output is an answer. Keeping the code is a new request — classify it.
"It grew, but I'm almost done — no need to re-classify"	Hidden complexity upgrades the path mid-task. Stop and say so.
"They approved the spike, so the follow-up change is approved too"	Each task gets its own classification and its own approval.

Checklist

Classify first, announce the path, then create a task for each item on your path and complete them in order.

Spike:

Explore project context — enough to frame the probe
Present question + probe plan — 2-3 sentences
Get approval — a nod is enough
Investigate — as cheaply as correctness allows
Report findings — a recommendation; label anything built as throwaway

Bounded:

Explore project context — check files, docs, recent commits
Ask clarifying questions — one at a time, the ones that matter
Present short design in chat — approach, files touched, testing
Get approval — STOP and wait for an explicit yes; presenting the design and starting in the same breath is skipping the gate
Implement — proceed with the normal development workflow (TDD applies); no plan document

Architectural:

Explore project context — check files, docs, recent commits
Offer the visual companion just-in-time — NOT upfront. The first time a question would genuinely be clearer shown than described, offer it then (its own message); on approval its browser tab opens for you. If no visual question ever arises, never offer it. See the Visual Companion section below.
Ask clarifying questions — one at a time, understand purpose/constraints/success criteria
Propose 2-3 approaches — with trade-offs and your recommendation
Present design — in sections scaled to their complexity, get user approval after each section
Write design doc — save to docs/superpowers/specs/YYYY-MM-DD-<topic>-design.md and commit
Spec self-review — quick inline check for placeholders, contradictions, ambiguity, scope (see below)
User reviews written spec — ask user to review the spec file before proceeding
Transition to implementation — invoke writing-plans skill to create implementation plan

Process Flow

digraph brainstorming {
    "Classify: spike / bounded / architectural" [shape=diamond];
    "Present question + probe (2-3 sentences)" [shape=box];
    "Ask clarifying questions (bounded)" [shape=box];
    "Present short design in chat" [shape=box];
    "Human approves?" [shape=diamond];
    "Investigate; report recommendation" [shape=doublecircle];
    "Implement via normal workflow (no plan doc)" [shape=doublecircle];
    "Explore project context" [shape=box];
    "Ask clarifying questions" [shape=box];
    "Propose 2-3 approaches" [shape=box];
    "Present design sections" [shape=box];
    "User approves design?" [shape=diamond];
    "Write design doc" [shape=box];
    "Spec self-review\n(fix inline)" [shape=box];
    "User reviews spec?" [shape=diamond];
    "Invoke writing-plans skill" [shape=doublecircle];
    "Hidden complexity? Upgrade path" [shape=box];

    "Classify: spike / bounded / architectural" -> "Present question + probe (2-3 sentences)" [label="spike"];
    "Classify: spike / bounded / architectural" -> "Ask clarifying questions (bounded)" [label="bounded"];
    "Classify: spike / bounded / architectural" -> "Explore project context" [label="architectural"];
    "Present question + probe (2-3 sentences)" -> "Human approves?";
    "Ask clarifying questions (bounded)" -> "Present short design in chat";
    "Present short design in chat" -> "Human approves?";
    "Human approves?" -> "Investigate; report recommendation" [label="spike: yes"];
    "Human approves?" -> "Implement via normal workflow (no plan doc)" [label="bounded: yes"];
    "Hidden complexity? Upgrade path" -> "Classify: spike / bounded / architectural";
    "Explore project context" -> "Ask clarifying questions";
    "Ask clarifying questions" -> "Propose 2-3 approaches";
    "Propose 2-3 approaches" -> "Present design sections";
    "Present design sections" -> "User approves design?";
    "User approves design?" -> "Present design sections" [label="no, revise"];
    "User approves design?" -> "Write design doc" [label="yes"];
    "Write design doc" -> "Spec self-review\n(fix inline)";
    "Spec self-review\n(fix inline)" -> "User reviews spec?";
    "User reviews spec?" -> "Write design doc" [label="changes requested"];
    "User reviews spec?" -> "Invoke writing-plans skill" [label="approved"];
}

Terminal states are path-bound. Architectural: the ONLY skill you invoke after brainstorming is writing-plans — never frontend-design, mcp-builder, or any other implementation skill. Bounded: after approval, implementation proceeds directly through the normal development workflow; no plan document. Spike: the terminal state is a reported recommendation.

The Process

The subsections below serve the bounded and architectural paths (a spike stops at "present the probe, get a nod"). Sections from Exploring approaches onward are architectural-path depth — for bounded work, context plus a few questions plus a short in-chat design is the whole process.

Understanding the idea:

Check out 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 → implementation cycle.
For appropriately-scoped projects, ask questions one at a time to refine the idea
Prefer multiple choice questions when possible, but open-ended is fine too
Only one question per message - if a topic needs more exploration, break it into multiple questions
Focus on understanding: purpose, constraints, success criteria

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
YAGNI ruthlessly - remove unnecessary features from every approach and design

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
Ask after each section whether it looks right so far
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 for you to work with - you reason better about code you can hold in context at once, and your edits are more reliable when files are focused. When a file grows large, that's often a signal that 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 (e.g., 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 (architectural path)

Documentation:

Write the validated design (spec) to docs/superpowers/specs/YYYY-MM-DD-<topic>-design.md
- (User preferences for spec location override this default)
Use elements-of-style:writing-clearly-and-concisely skill if available
Commit the design document to git

Spec Self-Review: After writing the spec document, look at it with fresh eyes:

Placeholder scan: Any "TBD", "TODO", incomplete sections, or vague requirements? Fix them.
Internal consistency: Do any sections contradict each other? Does the architecture match the feature descriptions?
Scope check: Is this focused enough for a single implementation plan, or does it need decomposition?
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 spec review loop passes, ask the user to review the written spec before proceeding:

"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 spec review loop. Only proceed once the user approves.

Implementation:

Invoke the writing-plans skill to create a detailed implementation plan
Do NOT invoke any other skill. writing-plans is the next step.

Visual Companion

A browser-based companion for showing mockups, diagrams, and visual options during brainstorming. Available as a tool — not a mode. Accepting the companion means it's available for questions that benefit from visual treatment; it does NOT mean every question goes through the browser.

Offering the companion (just-in-time): Do NOT offer it upfront. Wait until a question would genuinely be clearer shown than told — a real mockup / layout / diagram question, not merely a UI topic. The first time that happens, offer it then, as its own message:

"This next part might be easier if I show you — I can put together mockups, diagrams, and comparisons in a browser tab as we go. It's still new and can be token-intensive. Want me to? I'll open it for you."

This offer MUST be its own message. Only the offer — no clarifying question, summary, or other content. Wait for the user's response. If they accept, start the server with --open so their browser opens to the first screen automatically. If they decline, continue text-only and don't offer again unless they raise it.

Per-question decision: Even after the user accepts, decide FOR EACH QUESTION whether to use the browser or the terminal. The test: would the user understand this better by seeing it than reading it?

Use the browser for content that IS visual — mockups, wireframes, layout comparisons, architecture diagrams, side-by-side visual designs
Use the terminal for content that is text — requirements questions, conceptual choices, tradeoff lists, A/B/C/D text options, scope decisions

A question about a UI topic is not automatically a visual question. "What does personality mean in this context?" is a conceptual question — use the terminal. "Which wizard layout works better?" is a visual question — use the browser.

If they agree to the companion, read the detailed guide before proceeding: skills/brainstorming/visual-companion.md

Other files in this skill

spec-document-reviewer-prompt.md (verbatim)

Spec Document Reviewer Prompt Template

Use this template when dispatching a spec document reviewer subagent.

Purpose: Verify the spec is complete, consistent, and ready for implementation planning.

Dispatch after: Spec document is written to docs/superpowers/specs/

Subagent (general-purpose):
  description: "Review spec document"
  prompt: |
    You are a spec document reviewer. Verify this spec is complete and ready for planning.

    **Spec to review:** [SPEC_FILE_PATH]

    ## What to Check

    | Category | What to Look For |
    |----------|------------------|
    | Completeness | TODOs, placeholders, "TBD", incomplete sections |
    | Consistency | Internal contradictions, conflicting requirements |
    | Clarity | Requirements ambiguous enough to cause someone to build the wrong thing |
    | Scope | Focused enough for a single plan — not covering multiple independent subsystems |
    | YAGNI | Unrequested features, over-engineering |

    ## Calibration

    **Only flag issues that would cause real problems during implementation planning.**
    A missing section, a contradiction, or a requirement so ambiguous it could be
    interpreted two different ways — those are issues. Minor wording improvements,
    stylistic preferences, and "sections less detailed than others" are not.

    Approve unless there are serious gaps that would lead to a flawed plan.

    ## Output Format

    ## Spec Review

    **Status:** Approved | Issues Found

    **Issues (if any):**
    - [Section X]: [specific issue] - [why it matters for planning]

    **Recommendations (advisory, do not block approval):**
    - [suggestions for improvement]

Reviewer returns: Status, Issues (if any), Recommendations

visual-companion.md (verbatim)

Visual Companion Guide

Browser-based visual brainstorming companion for showing mockups, diagrams, and options.

When to Use

Decide per-question, not per-session. The test: would the user understand this better by seeing it than reading it?

Use the browser when the content itself is visual:

UI mockups — wireframes, layouts, navigation structures, component designs
Architecture diagrams — system components, data flow, relationship maps
Side-by-side visual comparisons — comparing two layouts, two color schemes, two design directions
Design polish — when the question is about look and feel, spacing, visual hierarchy
Spatial relationships — state machines, flowcharts, entity relationships rendered as diagrams

Use the terminal when the content is text or tabular:

Requirements and scope questions — "what does X mean?", "which features are in scope?"
Conceptual A/B/C choices — picking between approaches described in words
Tradeoff lists — pros/cons, comparison tables
Technical decisions — API design, data modeling, architectural approach selection
Clarifying questions — anything where the answer is words, not a visual preference

A question about a UI topic is not automatically a visual question. "What kind of wizard do you want?" is conceptual — use the terminal. "Which of these wizard layouts feels right?" is visual — use the browser.

How It Works

The server watches a directory for HTML files and serves the newest one to the browser. You write HTML content to screen_dir, the user sees it in their browser and can click to select options. Selections are recorded to state_dir/events that you read on your next turn.

Content fragments vs full documents: If your HTML file starts with <!DOCTYPE or <html, the server serves it as-is (just injects the helper script). Otherwise, the server automatically wraps your content in the frame template — adding the header, CSS theme, connection status, and all interactive infrastructure. Write content fragments by default. Only write full documents when you need complete control over the page.

Starting a Session

# Start AFTER the user approves the companion. --open auto-opens their browser on
# the first screen; --project-dir persists mockups and enables same-port restart.
scripts/start-server.sh --project-dir /path/to/project --open

# Returns: {"type":"server-started","port":52341,
#           "url":"http://localhost:52341/?key=ab12…",
#           "screen_dir":"/path/to/project/.superpowers/brainstorm/12345-1706000000/content",
#           "state_dir":"/path/to/project/.superpowers/brainstorm/12345-1706000000/state"}

Save screen_dir and state_dir from the response. With --open, the browser opens itself when you push the first screen — you don't need to ask the user to open it, but still share the URL as a fallback (headless/remote setups won't auto-open).

The URL contains a session key (?key=…). The server rejects any request without it, so always give the user the complete URL from the url field — never strip the query string, and never hand out a bare http://host:port. The key gates HTTP and WebSocket access so a stray browser tab or another machine on the network can't read the screens or inject events. After the first load the browser remembers the key via a cookie, so reloads and /files/* assets work without repeating it.

Finding connection info: The server writes its startup JSON to $STATE_DIR/server-info. If you launched the server in the background and didn't capture stdout, read that file to get the URL and port. When using --project-dir, check <project>/.superpowers/brainstorm/ for the session directory.

Note: Pass the project root as --project-dir so mockups persist in .superpowers/brainstorm/ and survive server restarts. Without it, files go to /tmp and get cleaned up. Remind the user to add .superpowers/ to .gitignore if it's not already there.

Launching the server by platform:

Claude Code:

# Default mode works — the script backgrounds the server itself.
scripts/start-server.sh --project-dir /path/to/project --open

On Windows, the script auto-detects and switches to foreground mode (which blocks the tool call). Use run_in_background: true on the Bash tool call so the server survives across conversation turns, then read $STATE_DIR/server-info on the next turn to get the URL and port.

Codex:

# Codex reaps background processes. The script auto-detects CODEX_CI and
# switches to foreground mode. Run it normally — no extra flags needed.
scripts/start-server.sh --project-dir /path/to/project --open

Gemini CLI:

# Use --foreground and set is_background: true on your shell tool call
# so the process survives across turns
scripts/start-server.sh --project-dir /path/to/project --open --foreground

Copilot CLI:

# Start it with Copilot CLI's non-blocking/background shell mechanism so the
# server survives across turns. Keep --foreground so the harness, not the
# script, owns backgrounding. The launcher is a .sh, so invoke it via bash
# (on Windows, call Git Bash's bash.exe from the PowerShell tool).
bash scripts/start-server.sh --project-dir /path/to/project --open --foreground

Other environments: The server must keep running in the background across conversation turns. If your environment reaps detached processes, use --foreground and launch the command with your platform's background execution mechanism.

If the URL is unreachable from your browser (common in remote/containerized setups), bind a non-loopback host:

scripts/start-server.sh \
  --project-dir /path/to/project \
  --host 0.0.0.0 \
  --url-host localhost

Use --url-host to control what hostname is printed in the returned URL JSON.

The Loop

Check server is alive, then write HTML to a new file in screen_dir:
- Required: confirm the server is alive before referring to the URL or pushing a screen. Check that $STATE_DIR/server-info exists and $STATE_DIR/server-stopped does not. If it has shut down, restart it with start-server.sh using the same --project-dir — it reuses the same port, so the user's open tab reconnects on its own (it shows a "paused" overlay while the server is down) and you don't need to send a new URL. The server auto-exits after 4 hours idle (configurable with --idle-timeout-minutes).
- Use semantic filenames: platform.html, visual-style.html, layout.html
- Never reuse filenames — each screen gets a fresh file
- Use your file-creation tool — never use cat/heredoc (dumps noise into terminal)
- Server automatically serves the newest file
Tell user what to expect and end your turn:
- Remind them of the URL (every step, not just first)
- Give a brief text summary of what's on screen (e.g., "Showing 3 layout options for the homepage")
- Ask them to respond in the terminal: "Take a look and let me know what you think. Click to select an option if you'd like."
On your next turn — after the user responds in the terminal:
- Read $STATE_DIR/events if it exists — this contains the user's browser interactions (clicks, selections) as JSON lines
- Merge with the user's terminal text to get the full picture
- The terminal message is the primary feedback; state_dir/events provides structured interaction data
Iterate or advance — if feedback changes current screen, write a new file (e.g., layout-v2.html). Only move to the next question when the current step is validated.
Unload when returning to terminal — when the next step doesn't need the browser (e.g., a clarifying question, a tradeoff discussion), push a waiting screen to clear the stale content:
```

<div style="display:flex;align-items:center;justify-content:center;min-height:60vh">
  <p class="subtitle">Continuing in terminal...</p>
</div>
```
This prevents the user from staring at a resolved choice while the conversation has moved on. When the next visual question comes up, push a new content file as usual.
Repeat until done.

Writing Content Fragments

Write just the content that goes inside the page. The server wraps it in the frame template automatically (header, theme CSS, connection status, and all interactive infrastructure).

Minimal example:

<h2>Which layout works better?</h2>
<p class="subtitle">Consider readability and visual hierarchy</p>

<div class="options">
  <div class="option" data-choice="a" onclick="toggleSelect(this)">
    <div class="letter">A</div>
    <div class="content">
      <h3>Single Column</h3>
      <p>Clean, focused reading experience</p>
    </div>
  </div>
  <div class="option" data-choice="b" onclick="toggleSelect(this)">
    <div class="letter">B</div>
    <div class="content">
      <h3>Two Column</h3>
      <p>Sidebar navigation with main content</p>
    </div>
  </div>
</div>

That's it. No <html>, no CSS, no <script> tags needed. The server provides all of that.

CSS Classes Available

The frame template provides these CSS classes for your content:

Options (A/B/C choices)

<div class="options">
  <div class="option" data-choice="a" onclick="toggleSelect(this)">
    <div class="letter">A</div>
    <div class="content">
      <h3>Title</h3>
      <p>Description</p>
    </div>
  </div>
</div>

Multi-select: Add data-multiselect to the container to let users select multiple options. Each click toggles the item's selected styling.

<div class="options" data-multiselect>
  <!-- same option markup — users can select/deselect multiple -->
</div>

Cards (visual designs)

<div class="cards">
  <div class="card" data-choice="design1" onclick="toggleSelect(this)">
    <div class="card-image"><!-- mockup content --></div>
    <div class="card-body">
      <h3>Name</h3>
      <p>Description</p>
    </div>
  </div>
</div>

Mockup container

<div class="mockup">
  <div class="mockup-header">Preview: Dashboard Layout</div>
  <div class="mockup-body"><!-- your mockup HTML --></div>
</div>

Split view (side-by-side)

<div class="split">
  <div class="mockup"><!-- left --></div>
  <div class="mockup"><!-- right --></div>
</div>

Pros/Cons

<div class="pros-cons">
  <div class="pros"><h4>Pros</h4><ul><li>Benefit</li></ul></div>
  <div class="cons"><h4>Cons</h4><ul><li>Drawback</li></ul></div>
</div>

Mock elements (wireframe building blocks)

<div class="mock-nav">Logo | Home | About | Contact</div>
<div style="display: flex;">
  <div class="mock-sidebar">Navigation</div>
  <div class="mock-content">Main content area</div>
</div>
<button class="mock-button">Action Button</button>
<input class="mock-input" placeholder="Input field">
<div class="placeholder">Placeholder area</div>

Typography and sections

h2 — page title
h3 — section heading
.subtitle — secondary text below title
.section — content block with bottom margin
.label — small uppercase label text

Browser Events Format

When the user clicks options in the browser, their interactions are recorded to $STATE_DIR/events (one JSON object per line). The file is cleared automatically when you push a new screen.

{"type":"click","choice":"a","text":"Option A - Simple Layout","timestamp":1706000101}
{"type":"click","choice":"c","text":"Option C - Complex Grid","timestamp":1706000108}
{"type":"click","choice":"b","text":"Option B - Hybrid","timestamp":1706000115}

The full event stream shows the user's exploration path — they may click multiple options before settling. The last choice event is typically the final selection, but the pattern of clicks can reveal hesitation or preferences worth asking about.

If $STATE_DIR/events doesn't exist, the user didn't interact with the browser — use only their terminal text.

Design Tips

Scale fidelity to the question — wireframes for layout, polish for polish questions
Explain the question on each page — "Which layout feels more professional?" not just "Pick one"
Iterate before advancing — if feedback changes current screen, write a new version
2-4 options max per screen
Use real content when it matters — for a photography portfolio, use actual images (Unsplash). Placeholder content obscures design issues.
Keep mockups simple — focus on layout and structure, not pixel-perfect design

File Naming

Use semantic names: platform.html, visual-style.html, layout.html
Never reuse filenames — each screen must be a new file
For iterations: append version suffix like layout-v2.html, layout-v3.html
Server serves newest file by modification time

Cleaning Up

scripts/stop-server.sh $SESSION_DIR

If the session used --project-dir, mockup files persist in .superpowers/brainstorm/ for later reference. Only /tmp sessions get deleted on stop.

Reference

Frame template (CSS reference): scripts/frame-template.html
Helper script (client-side): scripts/helper.js

Back to obra/superpowers (skills framework and dev methodology) or Agent skills.

brainstorming skill (obra/superpowers)