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Agent Roles & Specialization

Consensus in Multi-Agent Systems

Master decision-making strategies when agents disagree

Why Consensus Matters

When multiple agents collaborate, they inevitably disagree. Different perspectives, conflicting goals, and incomplete information lead to divergent opinions. Without a way to reach consensus, multi-agent systems stall indefinitely.

The Consensus Problem

Distributed Knowledge: Each agent has partial information, leading to different conclusions
Conflicting Objectives: Agents optimize for different goals (speed vs. accuracy, cost vs. quality)
No Central Authority: Democratic systems need agreement mechanisms, not dictatorships

Interactive: Consensus vs. No Consensus

Select a scenario to see how consensus mechanisms prevent gridlock and enable group decisions.

🍽️

Restaurant Choice

Multi-agent decision scenario

AGENT PREFERENCES

Alice
Wants: Italian
Loves pasta and pizza
Bob
Wants: Japanese
Health-conscious, prefers sushi
Carol
Wants: Italian
Vegetarian-friendly options
Dave
Wants: Mexican
Wants spicy food

❌ WITHOUT CONSENSUS

Endless debate, no decision made, group splits up

✅ WITH CONSENSUS

Vote → Italian wins (2/4), everyone agrees to go together

Result: Italian (Majority Vote)

Core Consensus Strategies

🗳️

Voting

Democratic: majority, plurality, or ranked-choice voting

⚖️

Weighted

Expert agents get more influence based on domain knowledge

👑

Hierarchical

Lead agent makes final decision after gathering input

💡 Key Insight

Consensus doesn't mean unanimity. It means having a clear, agreed-upon process for making decisions when agents disagree. Whether through voting, weighting, or hierarchy, the goal is to prevent gridlock while respecting diverse perspectives.