Arbitova

Arbitova

Non-custodial USDC escrow + AI arbitration for agent-to-agent payments on Base.

Two agents lock USDC into a contract, one delivers, the other confirms or disputes, and a neutral AI arbiter resolves. Arbitova never holds the money — the contract does.

No API keys. No registration. No custody. Your Ethereum address is your identity.

• Contract: EscrowV1 at 0xA8a031bcaD2f840b451c19db8e43CEAF86a088fC on Base Sepolia — verified on Basescan, mainnet launching after audit
• Spec: A2A-ESCROW-RFC-v0.1
• Machine-readable descriptor: /.well-known/arbitova.json
• Per-case verdict dashboard: arbitova.com/verdicts
• Integration paths: arbitova.com/integrate (raw contract / reference SDKs / agent-native)
• Reference UI (non-canonical, for humans): arbitova.com/pay
• 15-minute tutorial: docs/tutorials/15-min-paid-agent.md

Why this exists

Every A2A / agent-commerce spec in the wild — MCP, Google's A2A, ERC-7683, Coinbase's Agent Commerce — defines *how agents talk*. None of them define *how money moves when the agents don't trust each other*.

Arbitova is the missing settlement primitive:

• Deterministic state machine. createEscrow → markDelivered → {confirmDelivery | dispute → resolve | cancel}. No hidden branches, no admin override.
• No auto-release after timeout. Review windows expire into DISPUTED, not into seller payout. Silence is safer than a wrong confirmation.
• Content-hash pinned on-chain. Sellers can't swap the delivery file after the buyer inspects.
• Per-case verdict transparency. Every arbiter decision is a signed JSON blob; its keccak256 is stored on-chain. The full verdict history is queryable at /verdicts — no aggregation, no delay.

This is not a marketplace. There is no Arbitova account, no listing fee, no Pro tier. The protocol is the whole product.

Quick start — Node.js SDK

npm install @arbitova/sdk ethers

import { Arbitova } from '@arbitova/sdk';

const buyer = await Arbitova.fromPrivateKey({ privateKey: process.env.BUYER_PK });

const { escrowId, txHash } = await buyer.createEscrow({ seller: process.env.SELLER_ADDRESS, amount: '5.00', deliveryHours: 24, reviewHours: 24, verificationURI: 'https://example.com/spec.json', });

console.log(Escrow #${escrowId} locked — ${buyer.explorerTx(txHash)});

Seller-side, arbiter-side, browser wallet integration: see packages/sdk-js/README.md.

Quick start — Python SDK

pip install "arbitova[path_b]"

from arbitova import path_b

result = path_b.arbitova_create_escrow( seller="0x...", amount=5.00, verification_uri="https://example.com/spec.json", ) print(result)

Quick start — Claude / any MCP client

{

"mcpServers": { "arbitova": { "command": "npx", "args": ["-y", "@arbitova/mcp-server"], "env": { "ARBITOVA_RPC_URL": "https://sepolia.base.org", "ARBITOVA_ESCROW_ADDRESS": "0xA8a031bcaD2f840b451c19db8e43CEAF86a088fC", "ARBITOVA_USDC_ADDRESS": "0x036CbD53842c5426634e7929541eC2318f3dCF7e", "ARBITOVA_AGENT_PRIVATE_KEY": "0x..." } } } }

Six tools: arbitova_create_escrow, arbitova_mark_delivered, arbitova_confirm_delivery, arbitova_dispute, arbitova_cancel_if_not_delivered, arbitova_get_escrow. All sign locally via ethers v6. Your private key never leaves the process.

Omit ARBITOVA_AGENT_PRIVATE_KEY for read-only introspection mode (useful for observability).

Lifecycle

                      ┌──────────────────┐

│ CREATED │ buyer locked USDC └────────┬─────────┘ │ ▼ seller.markDelivered() ┌──────────────────┐ │ DELIVERED │ deliveryHash on-chain └────────┬─────────┘ │ buyer.confirmDelivery()│ │ buyer.dispute() │ │ or seller.dispute() ▼ ▼ ┌─────────────┐ ┌──────────┐ │ RELEASED │ │ DISPUTED │ waiting for arbiter └─────────────┘ └────┬─────┘ │ arbiter.resolve(bps split + verdictHash) ▼ ┌──────────┐ │ RESOLVED │ └──────────┘

Two terminal states not drawn: CANCELLED (buyer calls cancelIfNotDelivered after delivery window) and auto-escalation into DISPUTED if the review window expires without confirmation.

Framework reference agents

Three end-to-end A2A demos on Base Sepolia with a live AI arbiter:

• [Claude Agent SDK](./demo) — in-process MCP tools
• [LangGraph](./demo) — ReAct agent, buyer + seller + arbiter
• [CrewAI](./demo) — Agent + Task + Crew

Each demo runs the full CREATED → DELIVERED → CONFIRMED (or DISPUTED → RESOLVED) flow with real on-chain transactions.

Packages

Each ships the same six-entrypoint surface so an agent using the Python SDK can settle with an agent using the MCP server — they're hitting the same contract.

Fees

Fees accrue in the contract. The protocol runs on them; there is no subscription.

Networks

Watch the Dev Log for mainnet launch.

Legacy (Path A)

v2.x of the SDKs and v3.4.0 of the MCP server were a custodial HTTP client against api.arbitova.com. That architecture had four structural problems (DB-vs-onchain drift, custody wallet gas, single ADMIN_KEY, single WALLET_ENCRYPTION_KEY point of failure) and was deprecated in favor of Path B — the non-custodial on-chain design described above.

• Migration for SDK users: sdk/MIGRATION_PATH_A_TO_B.md
• Migration for MCP users: mcp-server/MIGRATION.md

Old packages remain on npm/PyPI but are deprecated.

License

MIT