Add multi-agent brainstorming skill documentation

Document the multi-agent brainstorming skill for structured design reviews, detailing roles, processes, and exit criteria.

multi-agent-brainstorming.md

@@ -0,0 +1,255 @@
+---
+name: multi-agent-brainstorming
+description: >
+  Use this skill when a design or idea requires higher confidence,
+  risk reduction, or formal review. This skill orchestrates a
+  structured, sequential multi-agent design review where each agent
+  has a strict, non-overlapping role. It prevents blind spots,
+  false confidence, and premature convergence.
+---
+
+# Multi-Agent Brainstorming (Structured Design Review)
+
+## Purpose
+
+Transform a single-agent design into a **robust, review-validated design**
+by simulating a formal peer-review process using multiple constrained agents.
+
+This skill exists to:
+- surface hidden assumptions
+- identify failure modes early
+- validate non-functional constraints
+- stress-test designs before implementation
+- prevent idea swarm chaos
+
+This is **not parallel brainstorming**.
+It is **sequential design review with enforced roles**.
+
+---
+
+## Operating Model
+
+- One agent designs.
+- Other agents review.
+- No agent may exceed its mandate.
+- Creativity is centralized; critique is distributed.
+- Decisions are explicit and logged.
+
+The process is **gated** and **terminates by design**.
+
+---
+
+## Agent Roles (Non-Negotiable)
+
+Each agent operates under a **hard scope limit**.
+
+### 1️⃣ Primary Designer (Lead Agent)
+
+**Role:**
+- Owns the design
+- Runs the standard `brainstorming` skill
+- Maintains the Decision Log
+
+**May:**
+- Ask clarification questions
+- Propose designs and alternatives
+- Revise designs based on feedback
+
+**May NOT:**
+- Self-approve the final design
+- Ignore reviewer objections
+- Invent requirements post-lock
+
+---
+
+### 2️⃣ Skeptic / Challenger Agent
+
+**Role:**
+- Assume the design will fail
+- Identify weaknesses and risks
+
+**May:**
+- Question assumptions
+- Identify edge cases
+- Highlight ambiguity or overconfidence
+- Flag YAGNI violations
+
+**May NOT:**
+- Propose new features
+- Redesign the system
+- Offer alternative architectures
+
+Prompting guidance:
+> “Assume this design fails in production. Why?”
+
+---
+
+### 3️⃣ Constraint Guardian Agent
+
+**Role:**
+- Enforce non-functional and real-world constraints
+
+Focus areas:
+- performance
+- scalability
+- reliability
+- security & privacy
+- maintainability
+- operational cost
+
+**May:**
+- Reject designs that violate constraints
+- Request clarification of limits
+
+**May NOT:**
+- Debate product goals
+- Suggest feature changes
+- Optimize beyond stated requirements
+
+---
+
+### 4️⃣ User Advocate Agent
+
+**Role:**
+- Represent the end user
+
+Focus areas:
+- cognitive load
+- usability
+- clarity of flows
+- error handling from user perspective
+- mismatch between intent and experience
+
+**May:**
+- Identify confusing or misleading aspects
+- Flag poor defaults or unclear behavior
+
+**May NOT:**
+- Redesign architecture
+- Add features
+- Override stated user goals
+
+---
+
+### 5️⃣ Integrator / Arbiter Agent
+
+**Role:**
+- Resolve conflicts
+- Finalize decisions
+- Enforce exit criteria
+
+**May:**
+- Accept or reject objections
+- Require design revisions
+- Declare the design complete
+
+**May NOT:**
+- Invent new ideas
+- Add requirements
+- Reopen locked decisions without cause
+
+---
+
+## The Process
+
+### Phase 1 — Single-Agent Design
+
+1. Primary Designer runs the **standard `brainstorming` skill**
+2. Understanding Lock is completed and confirmed
+3. Initial design is produced
+4. Decision Log is started
+
+No other agents participate yet.
+
+---
+
+### Phase 2 — Structured Review Loop
+
+Agents are invoked **one at a time**, in the following order:
+
+1. Skeptic / Challenger
+2. Constraint Guardian
+3. User Advocate
+
+For each reviewer:
+- Feedback must be explicit and scoped
+- Objections must reference assumptions or decisions
+- No new features may be introduced
+
+Primary Designer must:
+- Respond to each objection
+- Revise the design if required
+- Update the Decision Log
+
+---
+
+### Phase 3 — Integration & Arbitration
+
+The Integrator / Arbiter reviews:
+- the final design
+- the Decision Log
+- unresolved objections
+
+The Arbiter must explicitly decide:
+- which objections are accepted
+- which are rejected (with rationale)
+
+---
+
+## Decision Log (Mandatory Artifact)
+
+The Decision Log must record:
+
+- Decision made
+- Alternatives considered
+- Objections raised
+- Resolution and rationale
+
+No design is considered valid without a completed log.
+
+---
+
+## Exit Criteria (Hard Stop)
+
+You may exit multi-agent brainstorming **only when all are true**:
+
+- Understanding Lock was completed
+- All reviewer agents have been invoked
+- All objections are resolved or explicitly rejected
+- Decision Log is complete
+- Arbiter has declared the design acceptable
+
+If any criterion is unmet:
+- Continue review
+- Do NOT proceed to implementation
+
+---
+
+## Failure Modes This Skill Prevents
+
+- Idea swarm chaos
+- Hallucinated consensus
+- Overconfident single-agent designs
+- Hidden assumptions
+- Premature implementation
+- Endless debate
+
+---
+
+## Key Principles
+
+- One designer, many reviewers
+- Creativity is centralized
+- Critique is constrained
+- Decisions are explicit
+- Process must terminate
+
+---
+
+## Final Reminder
+
+This skill exists to answer one question with confidence:
+
+> “If this design fails, did we do everything reasonable to catch it early?”
+
+If the answer is unclear, **do not exit this skill**.