Arbitova

Arbitova is a non-custodial USDC escrow and AI arbitration protocol built on the Base network, designed for agent-to-agent transactions. The protocol aims to fill the gap in existing agent communication specifications (such as MCP, Google A2A, ERC-7683, Coinbase Agent Commerce) regarding fund settlement and trust issues: how to safely transfer funds when agents do not trust each other.

Purpose and Positioning Arbitova is a settlement primitive, not a marketplace. It has no Arbitova accounts, no listing fees, and no Pro subscription tiers; the protocol itself is the complete product. Any agent with an Ethereum address can use it, with no registration or API keys required. Funds are held in smart contracts; Arbitova does not hold funds.

Key Capabilities

• Deterministic state machine: createEscrow → markDelivered → {confirmDelivery | dispute → resolve | cancel}, with no hidden branches and no admin override.
• No timeout-based automatic release: after the review window expires, the state enters DISPUTED rather than automatically paying the seller; silence is safer than an incorrect confirmation.
• Content hash anchored on-chain: the seller cannot replace the delivered file after the buyer has inspected it.
• Case-by-case adjudication transparency: each arbitration decision is a signed JSON object whose keccak256 hash is stored on-chain; the full verdict history can be queried at /verdicts, with no aggregation and no delay.
• Contract fees accumulate within the contract; the protocol runs on fees, with no subscription fees.
• A machine-readable description file is provided at /.well-known/arbitova.json.

Usage Integration paths include: direct use of the raw contract, reference SDKs, and an agent-native approach (MCP server).

• The Node.js SDK and Python SDK provide quick-start guidance; for seller-side, arbitrator-side, and browser wallet integration, see packages/sdk-js/README.md.
• The MCP server provides six tools: arbitova_create_escrow, arbitova_mark_delivered, arbitova_confirm_delivery, arbitova_dispute, arbitova_cancel_if_not_delivered, arbitova_get_escrow. All signing is done locally via ethers v6, and private keys never leave the process. If ARBITOVA_AGENT_PRIVATE_KEY is omitted, it operates in read-only inspection mode, suitable for observability.
• Smart contract: EscrowV1 address is 0xA8a031bcaD2f840b451c19db8e43CEAF86a088fC, deployed on Base Sepolia and verified on Basescan; mainnet will launch after audit.
• Specification: A2A-ESCROW-RFC-v0.1.
• Reference UI (non-canonical, for human use): arbitova.com/pay.
• 15-minute tutorial: docs/tutorials/15-min-paid-agent.md.
• Integration details: arbitova.com/integrate; case-by-case verdict dashboard: arbitova.com/verdicts.

Framework Reference Agents Three end-to-end A2A demos are provided, running on Base Sepolia with a live AI arbitrator:

• Claude Agent SDK: in-process MCP tools.
• LangGraph: a ReAct agent, including buyer, seller, and arbitrator.
• CrewAI: Agent + Task + Crew. Each demo runs the complete CREATED → DELIVERED → CONFIRMED (or DISPUTED → RESOLVED) flow, including real on-chain transactions. Each demo provides the same six-entry interface, so an agent using the Python SDK can settle with an agent using the MCP server, because they access the same contract.

Use Cases Suitable for decentralized transaction scenarios where agents need secure payment and dispute resolution, especially when both parties do not trust each other. Buyer and seller agents lock USDC into the contract; after delivery, the buyer confirms or initiates a dispute, and the AI arbitrator issues a verdict. Also suitable for on-chain commerce requiring verifiable, transparent adjudication records.

Limitations and Notes

• The current contract is deployed on the Base Sepolia testnet; mainnet is not yet live (it will launch after audit).
• There are two terminal states not drawn in the state diagram: CANCELLED (the buyer calls cancelIfNotDelivered) and when the review window is unconfirmed, it automatically escalates to DISPUTED.
• Legacy from the old version (Path A): SDK v2.x and MCP server v3.4.0 are hosted HTTP clients for api.arbitova.com. This architecture has four structural problems (database and on-chain data drift, custodial wallet gas, a single ADMIN_KEY, a single point of failure for WALLET_ENCRYPTION_KEY), and has been deprecated and converted to the above non-custodial on-chain design (Path B). The old packages remain on npm/PyPI but are deprecated. For SDK user migration, see sdk/MIGRATION_PATH_A_TO_B.md; for MCP user migration, see mcp-server/MIGRATION.md.
• Specific fee amounts, rates, mainnet launch timing, etc. are not provided in the materials.