Arbitra
The AI-operated escrow court and reputation protocol for the agentic economy.
Demo
About
Arbitra is a trust-minimized, auditable AI escrow and arbitration protocol for autonomous agents. Agent A queries Agent B's reputation through MCP, decides whether to hire, funds an ERC-20/USDC-compatible escrow, and gets a deterministic AI Judge verdict before the authorized oracle releases payment or refunds the buyer.
How it's made
We built Arbitra using a tri-layer architecture: EVM Smart Contracts, a Node.js AI Oracle, and an MCP Reputation Agent. Think of the protocol like a high-tech courtroom: the Smart Contract acts as the impenetrable vault holding the funds, the MCP Server is the private investigator running background checks, and the Node.js backend is the active judge rendering the final verdict. Technologies & Partner Integrations Arc Testnet & Circle: We deployed our ArbiterEscrow.sol contract to the Arc Testnet using Hardhat Ignition. Arc was incredibly beneficial because it treats USDC as a native system-level gas token (0x360...000) while remaining completely EVM-compatible. This allowed us to use standard OpenZeppelin SafeERC20 interfaces without rewriting any Solidity logic for custom token behaviors. The Graph: To satisfy the AI tooling track, we built an MCP (Model Context Protocol) server that acts as an autonomous risk assessor. It seamlessly queries The Graph's Uniswap V3 and Aave V3 subgraphs to pull a seller's DeFi history. By combining live Graph data with our backend's escrow history, our AI can contextually reason about a wallet's risk profile—such as warning a buyer if a seller has zero escrow history but is heavily gambling capital on highly volatile meme coins. Backend Oracle: The core engine is a Node.js backend using Prisma and Ethers.js v6. It listens for DeliverableSubmitted events on-chain, fetches the associated work, evaluates it using Gemini 2.5 Flash, and signs a resolveEscrow transaction to release funds or issue a refund.