Brainstorming Skill

Asked to brainstorm, a model produces ten reasonable ideas that any competent person would list — which is retrieval, not ideation. Real brainstorming has two phases with a wall between them: diverge (volume, no judgment, deliberately weird) then converge (explicit criteria, honest scoring). This skill enforces the wall.

What This Skill Produces

• A divergent set: 20-40 ideas spanning distinct strategies, not ten variants of one idea
• A convergent shortlist: 3-5 selected against criteria named before scoring
• The reject ledger: what was set aside and why — half the value, always preserved

Required Inputs

Ask for (if not already provided):

• The problem or prompt, and what an idea must accomplish to count
• Constraints that are real (budget/tech/brand) vs assumed — challenge one assumed constraint deliberately
• What's been tried or rejected already (avoids retreading; also reveals the requester's hidden criteria)

Divergent Phase (no judgment permitted)

1. Quota past the obvious. The first 8-10 ideas are what anyone would say — produce them fast to exhaust them, then keep going; ideas 15-30 are where non-obvious lives.
2. Rotate strategies, don't rephrase. Generate down distinct axes, a few ideas per axis:
   • Inversion — what would make the problem worse? Reverse each answer
   • Extremes — the $0 version; the $10M version; the version shipping tomorrow
   • Transplant — how does a hospital / game studio / street market solve the equivalent?
   • Constraint removal — if [assumed constraint] vanished, what becomes possible?
   • Actor shift — the user solves it themselves / the community solves it / it never occurs at all (prevention)
   • Combination — force-merge two earlier ideas
3. Keep the weird tail. 20% of the set should make the requester slightly uncomfortable. A brainstorm with no bad ideas didn't explore the edges — the weird ones exist to stretch the space, and occasionally to win.
4. No evaluative language in this phase. Not even "(probably impractical)". Judgment leaks kill volume.

Convergent Phase (judgment, but named)

5. Write criteria before looking back at the list. 3-4 max, from the requester's actual situation (impact, feasibility-this-quarter, differentiation, reversibility…). Criteria chosen after re-reading the list get reverse-engineered to bless a favourite.
6. Score coarsely (✅/➖/❌ per criterion). False precision on creative options is theatre.
7. Shortlist 3-5 with one line each on why. Include one wildcard — highest-variance, criteria-marginal — labelled as such.
8. Preserve the rejects with reasons. "Rejected: needs a partnership we don't have (yet)" is a future idea with a trigger condition; a deleted reject is a repeated brainstorm next quarter.

Output Format

Brainstorm: [prompt]

Divergent set ([n] ideas, by strategy): [grouped list — no judgments attached]

Criteria (named before selection): 1) … 2) … 3) …

Shortlisted	[C1]	[C2]	[C3]	Why it made it
(3-5 rows, incl. 🃏 one wildcard)

Reject ledger: [idea → the criterion it failed → what would revive it]

Quality Checks

• ≥20 ideas spanning ≥5 distinct strategies — not variants of two ideas
• The weird tail exists (ideas that risk sounding silly)
• Zero evaluative language in the divergent set
• Criteria were stated before scoring, and trace to the requester's situation
• Rejects preserved with revival conditions

Anti-Patterns

• Do not judge while generating — one "(unrealistic)" mid-list collapses the whole divergent phase
• Do not produce ten polished-obvious ideas and stop — that's a search result, not a brainstorm
• Do not let the criteria appear after the list has been read — that's rationalising a favourite
• Do not delete the rejects — the ledger is half the artifact
• Do not ship the shortlist without the wildcard — a fully-safe shortlist means the exercise removed everything it was for