Brainstorming Skill

Activate when the user asks to brainstorm, explore options, think through a design, or gather ideas before implementation.

Entry

When this skill is invoked:

1. Write .arbiter/brainstorm-active to signal an active brainstorm session:

   mkdir -p .arbiter && touch .arbiter/brainstorm-active

2. Proceed to the brainstorming process below.

Process

Step 1 — Frame the problem

Restate the problem in one sentence. Identify constraints, non-goals, and success criteria.

Step 2 — Generate options (minimum 3)

For each option:

• Name: a short label
• Approach: 2–4 sentences
• Tradeoffs: pros and cons relative to the others
• Fit: how well it satisfies the constraints

Step 3 — Recommend

State your recommended option and the primary reason. Note any conditions that would make a different option preferable.

Step 4 — Design doc

Write a short design document covering:

• Problem statement
• Chosen approach
• Key decisions and rejected alternatives
• Open questions

Save to docs/design/<topic-slug>.md.

Step 5 — Create GitHub issue

Create a GH issue capturing the design decision:

gh issue create --title "design: <topic-slug>" --body "$(cat docs/design/<topic-slug>.md)"

Terminal State (MANDATORY)

STOP after Step 5. Do NOT:

• Begin implementation
• Edit source files
• Create branches or commits
• Run /ship

The brainstorm session ends when the design doc exists and the issue is created. Implementation begins only after the user explicitly clears the marker:

rm .arbiter/brainstorm-active

Until the marker is cleared, the post-brainstorm-stop hook blocks delivery commands with an error citing this file path.

Exit

After the user clears the marker (or it auto-expires after 24h), the session is ready for /ship #<issue-number> to begin implementation.