VetoVETO
Enter Console
Arbitrum Open House London 2026

Your AI agent tried to execute a volatile trade.Veto Said No.

A hybrid EVM/WASM execution sandbox on Robinhood Chain. Arbitrum Stylus acts as an on-chain math coprocessor — computing historical asset variance in real-time and physically preventing autonomous trading agents from executing dangerous or hallucinated transactions.

Launch Security ConsoleRun Live Demo

<15ms

Eval Latency

~90%

Gas Saved

Zero

Slipped Trades

Ecosystem:
ArbitrumArbitrum
Robinhood ChainRobinhood Chain
HackQuestHackQuest

WASM Risk Sandbox

Robinhood Chain · Arbitrum Sepolia

Agent
Veto
Vault
$ _ Select an asset and run dry-run...

Architecture

How Veto Works

1Agent Proposes Trade

AI Trading Agent

Detects a market opportunity. Builds a trade payload with 50 recent price data points bundled as calldata. Sends transaction to VetoVault.

2WASM Computes Risk

Stylus Coprocessor

Rust WASM processes the 50-point array in O(N), computing BPS variance in <15ms — using ~90% less gas than equivalent Solidity bytecode.

3Block or Execute

VetoVault Decision

Variance above threshold? Transaction reverts with VolatilityExceedsThreshold. Capital stays untouched.

Capabilities

System Architecture

Stylus Math Coprocessing

Decouple heavy computation from EVM. Historical variance and on-chain statistics computed using compiled Rust WASM — a fraction of pure-Solidity gas cost.

// Solidity (N=50)
gas: 142,160
// Stylus WASM (N=50)
gas: ~14,200

Zero-Trust Interception

Even fully compromised agents can't bypass Veto. Volatility thresholds are enforced at consensus — dangerous trades revert with O(1) gas, vault capital untouched.

revert VolatilityExceedsThreshold(
uint256 computed, // 2450
uint256 threshold // 1000
);

Calldata Optimistic Oracles

No Chainlink. No oracle latency. Prices travel as transaction calldata — submitted by the agent, validated on-chain by Stylus in <15ms. Manipulation-resistant by design.

fn executeSwap(
token: Address,
prices: Vec<U256>
) -> Result<()>

Deployed & Verified

Live on Arbitrum Sepolia

Production-deployed on Robinhood Chain — an Arbitrum Orbit testnet

Risk Engine

Stylus WASM Coprocessor

0x2c0eebee49b38b2fe363664077003339e7b45d64

VetoVault

Solidity EVM Contract

0xba53711364C0fde5F6e8D450CFAd2655ADA70eD2

Agent Wallet

Python Trading Agent EOA

0x2236AA5667BAbcB4218288517d6aE75bBbd486Af

Chain: Robinhood Chain  ·   Network: Arbitrum Sepolia  ·   Status: Live

Security Console

Your AI tried.
Veto said no.

Watch live trade interceptions in the security console. See real WASM variance computations blocking volatile agent transactions in real-time.

Open Security Console

Built For

Arbitrum

Arbitrum

Stylus Platform

Robinhood Chain

Robinhood Chain

Chain Infrastructure

HackQuest

HackQuest

Arbitrum London 2026

Overall — Robinhood Chain$40K
Best Agentic Project$7K
Grants$30K