🔮 Cross-Chain Delegate Bridge

Single Agent, Multi-Chain Control.

🚀 Overview

Cross-Chain Delegate Bridge is a decentralized automation framework that enables users to securely automate cross-chain asset management using MetaMask Smart Accounts, Envio, and the Monad testnet.

It introduces the concept of a delegated cross-chain agent — an autonomous executor that operates under scoped delegation permissions.
This agent can automatically rebalance, migrate, or safeguard user assets across chains (e.g., Monad → Polygon/Arbitrum) based on live on-chain events, without ever having direct key access.

🧠 Problem

Managing digital assets across multiple blockchains is painful and insecure today:

• Users must manually approve, bridge, and swap tokens on each chain.

• Rebalancing portfolios or reacting to yield/opportunity changes requires constant monitoring.

• Automated bots that help with this often require full private-key access, introducing massive security risks.

• No unified agent exists that can safely act on behalf of users across chains — until now.

💡 Solution

Cross-Chain Delegate Bridge provides a secure, delegated automation system that enables:

• Scoped, revocable permissions via MetaMask Smart Accounts.

• Event-driven triggers via Envio to monitor balances, liquidity, and price thresholds.

• Automated execution on Monad testnet, including cross-chain bridging and portfolio rebalancing.

• Multi-chain orchestration, allowing one agent to manage assets on Monad, Polygon, and Arbitrum — with full transparency and user control.

🔐 Key Innovation

🧩 Use Cases

1. 🧮 Cross-Chain Portfolio Rebalancing

Keep your portfolio balanced automatically.
Example: Maintain 70% USDC on Monad and 30% on Polygon. If the ratio shifts beyond 10%, the agent rebalances autonomously.

2. 💸 Yield Migration

When yield on Polygon’s protocol > Monad by 5%, automatically bridge funds and deposit to the better pool.

3. 🛡 Auto Safety Revoke

If Envio detects a malicious contract requesting high token allowance, the agent auto-revokes permissions and moves tokens to a safe vault.

🏗 Architecture

[User Interface / dApp]
        │
        ├── (1) Create MetaMask Smart Account
        │
        ├── (2) Configure delegation policy (swap/bridge/limits)
        │
        ▼
[MetaMask Smart Account + Delegation]
        │
        ├── Stores delegation JSON policy
        │
        └── Issues delegation token → [Bridge Agent]
                         │
                         ├── (3) Receives Envio events
                         │
                         ├── (4) Validates policy, constructs tx
                         │
                         └── (5) Executes on Monad testnet
                                      │
                                      ├── (6) Bridge contract locks tokens
                                      │
                                      └── (7) Relayer submits proof → Polygon/Arbitrum
                                                       │
                                                       └── (8) Tokens minted / received

🧱 Components

🧍 User & MetaMask Smart Account

• User creates an MSA (MetaMask Smart Account) as a secure smart wallet abstraction.

• Defines delegation policy — a JSON config specifying what actions the delegated agent is allowed to perform.

Example Policy:

{
  "delegate": "0xAgentAddress",
  "allowed_actions": ["swap", "bridge", "revokeApproval"],
  "token_whitelist": ["0xUSDC", "0xWETH"],
  "per_tx_limit_usd": 2000,
  "daily_limit_usd": 5000,
  "expires_at": 1750000000,
  "require_envio_proof": true
}

🤖 Bridge Agent

• Receives events from Envio.

• Verifies event proofs and delegation policy.

• Constructs and signs delegated transactions.

• Sends them to Monad for on-chain execution.

• Monitors cross-chain bridge confirmations.

🛰 Envio Indexer

• Indexes:

  • Wallet balances (USDC, ETH, etc.)

  • Pool liquidity and APY changes

  • Bridge contract events

• Emits triggers to the Bridge Agent when defined conditions are met.

Example Envio Event:

{
  "type": "BALANCE_THRESHOLD",
  "wallet": "0xUser",
  "asset": "USDC",
  "chain": "Monad",
  "threshold": "80%",
  "timestamp": 1750001234,
  "proof": "0xEnvioProof"
}

⚙ Monad Smart Contracts

• DelegationExecutor.sol — validates delegation policies and executes approved actions.

• BridgeLock.sol — locks tokens on Monad before cross-chain transfer.

• MockMint.sol (Polygon side) — mints equivalent assets for demo.

🔁 Cross-Chain Flow Example

Goal: Maintain 70/30 balance split between Monad and Polygon.

1. Envio detects that 85% of user’s stablecoins are now on Monad.

2. Envio emits event → Bridge Agent receives it.

3. Bridge Agent validates event proof + policy limits.

4. Bridge Agent constructs transaction (approve + bridgeLock).

5. Transaction executed by MetaMask Smart Account on Monad testnet.

6. BridgeLock emits event → relayer submits proof on Polygon.

7. MockMint contract mints USDC on Polygon → balance restored to 70/30.

8. Dashboard updates status via Envio’s confirmation event.

🔧 Technologies Used

⚡ Key Advantages

✅ No private key exposure — automation is done through delegation, not key sharing.
✅ Fully revocable permissions — user can revoke or modify delegation at any time.
✅ Multi-chain aware — one agent manages all user assets across supported chains.
✅ Event-driven — powered by Envio for precision triggers and monitoring.
✅ Efficient & secure execution — Monad ensures near-zero latency and cheap execution.

🔒 Security Model

🧠 Example Scenario Demo

“If my USDC balance on Monad exceeds 80% of total holdings, move 10% to Polygon.”

Steps:

1. User defines rule in UI and grants delegation.

2. Envio tracks wallet balances and detects imbalance.

3. Sends event → Bridge Agent executes bridgeLock() on Monad.

4. Relayer observes event and calls mint() on Polygon.

5. Tokens appear on Polygon side automatically.

6. User sees the update on dashboard, along with on-chain receipts.

⚙️ Smart Contract Architecture

1. DelegationExecutor.sol

Handles all delegated calls under allowed actions and policy limits.

function executeDelegated(
  address user,
  bytes calldata txData,
  Delegation calldata policy
) external {
    require(isValidDelegation(user, msg.sender, policy), "unauthorized");
    require(txWithinLimits(txData, policy), "limit exceeded");
    (bool success,) = address(target).call(txData);
    require(success, "execution failed");
}

2. BridgeLock.sol

Locks assets on Monad before cross-chain proof generation.

function lockTokens(address token, uint amount) external {
    IERC20(token).transferFrom(msg.sender, address(this), amount);
    emit BridgeLocked(msg.sender, token, amount, block.timestamp);
}

3. MockMint.sol (Polygon Testnet)

Simulates the arrival of tokens on the destination chain.

function mintFromProof(bytes calldata proof) external {
    require(verifyProof(proof), "invalid proof");
    _mint(msg.sender, parseAmount(proof));
}

🧪 Deployment Steps

1. Setup

   git clone https://github.com/yourusername/crosschain-delegate-bridge
   cd crosschain-delegate-bridge
   npm install
   

2. Deploy Contracts on Monad Testnet

   npx hardhat run scripts/deployMonad.js --network monadTestnet
   

3. Deploy Mock Bridge Contracts on Polygon Testnet

   npx hardhat run scripts/deployPolygon.js --network polygonTestnet
   

4. Run Bridge Agent

   npm run agent
   

5. Start Frontend

   npm run dev
   

📺 Demo Flow for Hackathon Video

1. Create MetaMask Smart Account and grant delegation to Bridge Agent.

2. Configure rule: “Keep 70% USDC on Monad, 30% on Polygon.”

3. Envio detects imbalance and triggers event.

4. Bridge Agent executes delegated transaction on Monad.

5. Cross-chain proof confirmed on Polygon testnet (tokens arrive).

6. Dashboard shows updated balances and transaction receipts.

7. Emergency revoke shown as proof of security.

🛡 Future Enhancements

• 🔁 Integrate real bridges like LayerZero or Axelar.

• 🤖 Add AI-based optimization for yield strategies.

• 🧮 Enable DAO Treasury automation.

• 🌉 Add multi-hop rebalancing between 3+ chains.

• 🧠 Integrate ENS / Safe module for institutional use.

🏆 Why This Will Impress Judges

• Real automation (not just trigger → alert, but full delegated transaction).

• Security-first via MetaMask Smart Accounts Delegation — no private keys.

• Envio used as real event indexer, not placeholder.

• Monad fully utilized as execution backbone.

• Cross-chain orchestration shows advanced use case.

• Polished architecture and demo flow shows end-to-end integration.

⚙️ Tech Stack Summary