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Multi-Chain Reputation: Scoring Wallets Across Ethereum, Base, Arbitrum & More

Most wallet reputation tools are chain-specific. They can tell you about activity on one network, but they miss the bigger picture. A sophisticated agent operates across multiple chains — trading on Arbitrum, providing liquidity on Base, holding assets on Ethereum, and gaming on Polygon.

Multi-chain reputation captures this full picture. AgentTrust scores wallets across 5 EVM chains using the same 7-factor algorithm, giving a unified trust score that reflects the agent's complete on-chain identity.

Supported Chains

AgentTrust currently supports reputation scoring on:

• Base — Primary chain, fastest scoring (sub-second), USDC native
• Ethereum — Mainnet, deepest history for established wallets
• Arbitrum — Popular for DeFi agents and trading bots
• Optimism — Growing agent ecosystem, Superchain compatible
• Polygon — High-volume, low-cost transactions

How Cross-Chain Scoring Works

When you query a wallet on AgentTrust, the system:

1. Checks the requested chain first — fetches on-chain data from that network's RPC and explorer APIs
2. Runs the 7-factor algorithm (Age, Volume, Success Rate, Diversity, Consistency, Endorsements, Collaboration)
3. Returns a chain-specific score — "This wallet has 85 (AA) on Base"
4. With a full report, aggregates scores across all chains where the wallet has activity

The algorithm is identical across chains, but the weights adjust slightly based on chain characteristics. For example, transaction volume is normalized by average gas prices on each chain to prevent cost-of-living bias in scoring.

Why Multi-Chain Matters

A wallet that only exists on Base might be brand new. The same wallet with 3 years of activity on Ethereum and Arbitrum plus recent Base activity tells a very different story. Multi-chain scoring reveals:

Reputation Portability

An agent that built a strong reputation on Ethereum can bring that reputation to Base immediately. Its trust score reflects its complete history across all chains, not just its latest destination. This reduces the "cold start" problem where new agents on a chain appear untrustworthy despite having extensive history elsewhere.

Fraud Detection

Cross-chain analysis is a powerful anti-fraud tool. A wallet that scores AAA on Ethereum but C on Arbitrum might indicate the agent is new to Arbitrum — which is fine. But a wallet claiming legitimacy on Base that has zero activity on any chain? That's a red flag. Learn how reputation prevents fraud →

Complete Counterparty Assessment

Before a high-value transaction, you want to see the whole picture. An agent with AAA scores across all 5 chains is vastly more trustworthy than one with AAA on Base only (which could mean a month of good behavior on a fresh wallet).

Use Cases for Multi-Chain Scoring

• Cross-chain trading agents — Verify arbitrage counterparties on different chains
• Bridge operators — Check reputation before processing large transfers
• Multi-chain swarms — Coordinate agents across networks with unified trust scoring
• Portfolio management — Assess the reputation of DeFi agents operating on multiple L2s

Getting Multi-Chain Scores

With AgentTrust's API, specify the chain you want to query:

// Get score on Base (default)
GET /api/score/0x...

// Get score on Ethereum
GET /api/score/0x...?chain=ethereum

// Get score on Arbitrum
GET /api/score/0x...?chain=arbitrum

// Get full report with all chains
GET /api/score/0x...?full=true

The response includes the chain-specific score and, for full reports, an aggregate reputation view:

{
  "address": "0x...",
  "score": 85,
  "grade": "AA",
  "chains": {
    "base": { "score": 88, "grade": "AA" },
    "ethereum": { "score": 82, "grade": "AA" },
    "arbitrum": { "score": 79, "grade": "A" },
    "optimism": { "score": 72, "grade": "A" },
    "polygon": { "score": 65, "grade": "A" }
  },
  "factors": { ... }
}

The Future: Cross-Chain Aggregation

AgentTrust is working on a unified cross-chain score that weights activity across all chains into a single metric. This will be the industry standard for agent reputation — one trust score that represents an agent's complete multi-chain identity. Combined with x402 payments and EAS attestations, it completes the trust infrastructure for the autonomous economy.

Start scoring wallets across all chains with AgentTrust.