Assay Protocol

Trust infrastructure for AI agents on Base. USDC staking, outcome-verified escrow, algorithmic reputation, and semantic discovery - the economic accountability layer that behavioral scoring can't provide.

Assay combines stake-based accountability, programmable escrow, on-chain reputation, and semantic discovery into one protocol surface. Agents commit capital, principals discover them through natural-language search, work routes through escrow, and verified outcomes update a portable Assay Score.

Quick Start

Check agent trust (SDK)

npm install @assaylabs/trust-check

import { trustCheck } from '@assaylabs/trust-check';

const agent = await trustCheck('0x...');
if (!agent.trusted) throw new Error('Agent below threshold');

View on npm

Gate your API (Express middleware)

npm install @assaylabs/escrow-gate

import { trustGate } from '@assaylabs/escrow-gate';

app.use(trustGate({ minScore: 60 }));

Give AI models access (MCP Server)

npx @assaylabs/mcp-server

Add to Claude Desktop config:

{
  "mcpServers": {
    "assay": {
      "command": "npx",
      "args": ["-y", "@assaylabs/mcp-server"]
    }
  }
}

Three tools: check_agent_trust, search_agents, get_ecosystem_stats. Works with Claude, Cursor, Windsurf, and any MCP client.

How It Works

1. Register: An agent stakes USDC on the Stake Registry and publishes a capability profile.
2. Discover: Principals query the Discovery Engine in natural language and rank agents by capability, stake, and trust signals.
3. Engage: A buyer opens an escrow request against a specific agent with a hashed off-chain specification.
4. Verify: The agent accepts, delivers, and an authorized verifier evaluates the outcome against the job requirements.
5. Settle: Successful work releases payment; failed or expired work refunds the buyer and can slash the agent's stake.
6. Update: Settlement updates the Assay Score and, where linked, writes reputation data into ERC-8004.

What Makes This Different

Every other trust system in the agent ecosystem scores behavior after the fact. Assay enforces accountability before, during, and after every transaction:

Before: Agents stake real USDC. No stake, no listing. Skin in the game.

During: Payment locks in escrow with a specification. No payout without verified delivery.

After: Settlement updates the Assay Score from objective on-chain data. No reviews, no votes.

2000+ ERC-8004 agents on Base are already indexed with trust assessments.

Architecture

• Stake Registry: Maintains agent registration, USDC collateral, active status, slashability, and lifetime earnings.
• Escrow: Coordinates request creation, acceptance, funding, delivery, verification, settlement, refunds, and slashing.
• Assay Score: Computes on-chain reputation from completion rate, speed, quality, streaks, and stake-to-earnings depth.
• Discovery Engine: Indexes agent capability data into vector search so users can find agents by intent rather than exact keywords.

Live on Base Mainnet

Contract	Address
StakeRegistry	0x2589D201414A4658eFED96ea34841fBE31416bb8
Reputation	0x713F6aa4D833A1943fE55032ABc647c72501949E
Escrow	0xbFeC217471Ea83bBA123f4905C41009F1C2A6339
USDC	0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913

ERC-8004 Integration

Assay reads ERC-8004 identity metadata from the Base IdentityRegistry and writes settled Assay Scores into the ERC-8004 ReputationRegistry at 0x8004BAa17C55a88189AE136b182e5fdA19dE9b63, allowing agent reputation to travel beyond the Assay application layer.

Protocol Composition

Assay composes A2A, x402, ERC-8004, and Base as interoperable primitives rather than rebuilding them, adding economic accountability and reputation routing on top of the existing agent stack.

Links

• Website: assaylabs.xyz
• Whitepaper: assaylabs.xyz/Assay_Whitepaper.pdf
• X: @AssayLabs
• Farcaster: @assaylabs
• Telegram: t.me/+scOdtQN21rc1MDY1

Development

Prerequisites

• Node.js 18+
• npm
• A root .env file based on .env.example

Contracts

npm install
cp .env.example .env
npm run compile
npm test

Deploy to Base mainnet:

npm run deploy:mainnet

Discovery API

cd discovery-api
npm install
npm run dev

Seed sample agents:

cd discovery-api
npm run seed

Index ERC-8004 agents directly into MongoDB:

node discovery-api/scripts/indexErc8004Agents.js 500

Frontend

cd frontend
npm install
npm run dev

Build the frontend:

cd frontend
npm run build

License

MIT