paycrow

The trust layer for agent-to-agent commerce. Escrow protection with real dispute resolution for x402 payments on Base.

Agents pay for API calls with USDC via x402. But payments are final — no refunds, no disputes, no recourse. Every other escrow service says "no disputes, no chargebacks." PayCrow is different: funds are locked until delivery is verified, with on-chain dispute resolution if something goes wrong.

Install as an MCP server. Your agent gets trust-informed, escrow-protected payments.

Quick Start

1. Generate a wallet

npx paycrow init

Creates a fresh wallet and prints your Claude Desktop config — copy-paste and go.

2. Fund it

Send a small amount of ETH (for gas, ~$0.50) and USDC (for payments) to the printed address on Base.

3. Add to Claude Desktop

{
  "mcpServers": {
    "paycrow": {
      "command": "npx",
      "args": ["paycrow"],
      "env": {
        "PRIVATE_KEY": "0x_YOUR_KEY_FROM_INIT"
      }
    }
  }
}

Restart Claude Desktop. Done.

Trust-only mode (no wallet needed)

If you only want trust scoring without escrow, skip the wallet setup:

{
  "mcpServers": {
    "paycrow": {
      "command": "npx",
      "args": ["paycrow"]
    }
  }
}

trust_gate and trust_score_query work without PRIVATE_KEY. Escrow/payment tools will prompt you to set one up.

Any MCP Client

PRIVATE_KEY=0x... npx paycrow

Runs over stdio. Compatible with Claude Desktop, Claude Code, Cursor, Windsurf, OpenClaw, etc.

Tools (9 total)

safe_pay — Recommended

The smart way to pay an agent. Checks their trust score first, then auto-configures escrow protection based on risk.

Flow: Check trust → Set protection → Create escrow → Call API → Verify → Release or dispute

Protection levels (automatic):
  High trust agent   → 15min timelock, proceed normally
  Moderate trust     → 60min timelock, $25 cap
  Low trust          → 4hr timelock, $5 cap
  Unknown/caution    → BLOCKED — won't send funds

Parameters:
  url               — API endpoint to call
  seller_address    — Ethereum address of the agent
  amount_usdc       — Payment amount ($0.10 - $100)
  method            — GET, POST, PUT, DELETE (default: GET)
  headers           — HTTP headers (optional)
  body              — Request body (optional)

trust_gate — Check Before You Pay

Should you pay this agent? Returns a go/no-go decision with recommended escrow parameters.

Parameters:
  address               — Ethereum address to check
  intended_amount_usdc  — How much you plan to pay (optional)

Returns:
  decision              — proceed / proceed_with_caution / do_not_proceed
  escrowParams          — recommended timelock and max amount
  trustScore            — 0-100 score
  warning               — if intended amount exceeds safe limit

trust_score_query — Full Breakdown

Full trust score from 4 on-chain sources: PayCrow escrow history (40%), ERC-8004 identity (25%), Moltbook karma (15%), and Base chain activity (20%).

trust_onchain_quick — Free Fast Check

PayCrow reputation only. No API keys needed. Free.

x402_protected_call — Advanced

Manual escrow with full control over verification (JSON Schema or hash-lock) and timelock. Use when safe_pay's automatic protection isn't enough.

escrow_create

Create a USDC escrow with built-in dispute resolution.

escrow_release

Confirm delivery and release funds to the seller.

escrow_dispute

Flag bad delivery. Locks funds for arbiter review — the only escrow on Base with real dispute resolution.

escrow_status

Check the current state of an escrow.

How It Works

Agent (buyer) ──→ paycrow ──→ Check trust ──→ Create escrow ──→ Call API
                                                    │
                                              Verify response
                                                    │
                                     ┌──────────────┴──────────────┐
                                 Valid response              Bad response
                                     │                            │
                                Auto-release              Auto-dispute
                              (seller paid)           (arbiter reviews)

Escrow lifecycle:

FUNDED → RELEASED         (delivery confirmed, seller paid minus 2% fee)
       → DISPUTED → RESOLVED  (arbiter rules: splits funds)
       → EXPIRED → REFUNDED   (timeout: full refund, no fee)

• 2% protocol fee on release/resolve. Zero fee on refund.
• $0.10 minimum, $100 maximum per escrow (v1 safety cap).
• Timelock: 5 minutes to 30 days.
• On-chain reputation auto-recorded for every escrow outcome.

Why PayCrow

| Feature | PayCrow | Others | |---------|---------|--------| | Escrow | Yes (Base, USDC) | Some | | Dispute resolution | Yes — on-chain arbiter | No — "no disputes, no chargebacks" | | Trust scoring | 4 on-chain sources | Limited or none | | Trust-informed escrow | safe_pay auto-protects | Manual only | | MCP server | 9 tools | 0-1 tools | | Price | $0.001/trust query | $0.001-0.05 |

Environment Variables

| Variable | Required | Description | |----------|----------|-------------| | PRIVATE_KEY | For escrow tools | Wallet private key (hex, with 0x prefix) | | CHAIN | No | "base" for mainnet, defaults to Base Sepolia | | BASESCAN_API_KEY | No | For Base chain activity data (free at basescan.org) | | MOLTBOOK_APP_KEY | No | For Moltbook social reputation | | BASE_RPC_URL | No | Custom RPC URL for Base mainnet |

Chain

| | Testnet | Mainnet | |-|---------|---------| | Network | Base Sepolia | Base | | USDC | 0x036CbD53842c5426634e7929541eC2318f3dCF7e | 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 | | Gas cost | ~$0.005/escrow cycle | ~$0.005/escrow cycle |

Set CHAIN=base for mainnet. Defaults to Base Sepolia.

Contract

Solidity smart contracts with:

• Escrow: full 7-state machine with 2% protocol fee
• Reputation: on-chain trust scores based on escrow history
• Dispute resolution: arbiter can review and split funds
• OpenZeppelin ReentrancyGuard + Pausable
• 135 tests (unit + fuzz + invariant + integration)

Source: github.com/michu5696/paycrow

License

MIT