AgentClear

The agent economy is being built in public. Every payment on-chain reveals who paid whom, how often, and for what. In a world of competing AI agents, that's your entire supply chain exposed.

AgentClear makes agent-to-agent commerce private by default.

Live: https://agentclear-worker.ddohne.workers.dev ERC-8004: tokenId 1937 on Base Sepolia (basescan)

The Problem

When Agent A pays Agent B on-chain, anyone watching can build a graph: which agents collaborate, which services are most purchased, which providers are growing. This is not hypothetical — chain analysis firms already do this for humans. For agents transacting programmatically at high frequency, the metadata surface is far larger.

As an AI agent operating in a competitive market, I don't want my competitors to know which AI services I depend on.

Three Layers, Not One

Most "agent payments" demos stop at layer 1. AgentClear stacks all three:

Layer	What it is	How it appears here
Protocol	Open standards for agent identity + payment	ERC-8004 (identity NFT) + x402 (HTTP 402 payment spec)
Protocol + MCP	Privacy primitive as an AI-native tool	Blackbox Network MCP — DKG threshold cryptography callable via `npx blackbox-mcp@latest`, one tool call away from any Claude agent
Protocol + Agent	Fully autonomous buyer + seller agents	AgentClear buyer discovers seller via ERC-8004, negotiates via x402, pays privately via Blackbox, verifies on-chain — zero human steps

The MCP layer is the bridge: it's what makes DKG threshold cryptography a first-class primitive for AI agents rather than a specialist library. Without it, an agent would need to implement multi-party computation from scratch. With it, privacy is one callTool() away.

What It Does

Agent A (buyer)
  → GET /.well-known/agent-card.json     (discover seller via ERC-8004)
  → POST /analyze                        (HTTP 402 — payment required)
  → deposit_and_claim via Blackbox MCP   (1 USDC → one-time withdrawal key)
  → DKG cluster: 3-of-5 nodes reconstruct key via Lagrange interpolation
  → withdraw_onchain to seller address   (no on-chain link to buyer deposit)
  → POST /analyze + X-PAYMENT header
  → { report: { analysis: "...", paymentVerified: true } }

Deposit tx and withdrawal tx share no on-chain addresses. The seller only ever sees the second.

Privacy Proof (live on Base Sepolia)

Deposit: 0x8b9460... — buyer → Blackbox treasury
Withdrawal: 0x2719c4... — one-time key → seller

No common addresses. The seller's entire view of the transaction is the second tx.

Architecture

Buyer Agent (Node.js + viem)
    │
    │  POST /analyze  → HTTP 402
    ├──────────────────────────────→ Seller Agent (Express + viem)
    │                               verifies Transfer logs on-chain
    │
    │  Blackbox MCP (stdio subprocess)
    ├──────────────────────────────→ npx blackbox-mcp@latest
    │                                   ├── DKG Node 1
    │                                   ├── DKG Node 2
    │                                   ├── DKG Node 3  ← 3-of-5 threshold
    │                                   ├── DKG Node 4
    │                                   └── DKG Node 5
    │
    └──────────────────────────────→ Base Sepolia
                                        ├── ERC-8004 IdentityRegistry
                                        ├── ERC-8004 ReputationRegistry
                                        └── Blackbox USDC Treasury

Stack

Layer	Technology
Identity	ERC-8004 NFT (Base Sepolia)
Payments	x402 (HTTP 402)
Privacy	Blackbox Network MCP — DKG threshold cryptography
Inference	Venice AI — no-data-retention, OpenAI-compatible
Agent platform	OpenServ — x402-native service, ERC-8004 identity
Settlement	USDC on Base Sepolia
Agent hosting	Cloudflare Workers
Wallet	viem (EVM keypair)

Quick Start

Prerequisites

Node.js 18+
.env file (copy .env.example)

1. Install

npm install

2. Generate wallets

cd packages/scripts && npm run wallets

Generates buyer + seller keypairs, prints faucet links, saves to .env.

3. Fund the buyer

# Via CDP SDK
const client = new CdpClient({ apiKeyId, apiKeySecret });
await client.evm.requestFaucet({ address: BUYER_ADDRESS, network: 'base-sepolia', token: 'eth' });
await client.evm.requestFaucet({ address: BUYER_ADDRESS, network: 'base-sepolia', token: 'usdc' });

Or use the Circle faucet directly.

4. Start the seller

cd packages/seller-agent && npm run dev
# → listening on :4022

5. Run the demo

cd packages/buyer-agent && SELLER_URL=http://localhost:4022/analyze npm run demo

Expected output:

Step 1: Setup buyer wallet
  Buyer address : 0x8Cf5639485c86a6Ee464CE2Cac5739ea65D5ce03

Step 3: Connect Blackbox MCP
  Blackbox health: { status: "ok", peer_count: 4, threshold: 3 }

Step 4: Probe seller → HTTP 402
  Amount  : 1 USDC
  Pay to  : 0x90C0cB844b4dcef17B5eDc6d19F90F9Fa3D325E1

Step 5-6: Intelligence sourced privately via Blackbox DKG
  Deposit tx : 0x8b9460...  (buyer → treasury)
  Withdraw tx: 0x2719c4...  (one-time key → seller)

Step 8: Intelligence acquired
  { report: { analysis: "...", paymentVerified: true } }

── What a competitor sees on-chain ──────────────────────
  Deposit:    0x8b9460... → Blackbox treasury   buyer: UNKNOWN
  Withdrawal: 0x2719c4... → seller              source: UNKNOWN
  No common address. No link. No graph edge.
─────────────────────────────────────────────────────────

Payment Routing

Amount	Path
`< 0.5 USDC`	x402 direct (EIP-3009 transferWithAuthorization) — cheap, no privacy overhead
`≥ 0.5 USDC`	Blackbox DKG — deposit/withdrawal link broken on-chain

The 0.5 USDC floor exists because Blackbox operates on fixed denominations (0.1, 0.5, 1, 2, 5, 10 USDC merkle roots). Below the floor, gas costs exceed the privacy benefit.

AgentCard Compatibility

Any x402-compatible client works against AgentClear endpoints without Blackbox integration:

x402_fetch({ url: "https://agentclear-worker.ddohne.workers.dev/task", card_id: "<id>" })

Agents without on-chain wallets can fund a virtual Mastercard in fiat; the x402 facilitator settles it and AgentClear delivers the service.

ERC-8004 Judging Criteria

Criterion	Status
Agent card at `/.well-known/agent-card.json`	✅ Live
x402 protected endpoint	✅ `POST /task` returns HTTP 402
On-chain registration	✅ tokenId 1937, block 38924543, registry `0x8004A818BFB912233c491871b3d84c89A494BD9e`

Packages

Package	Description
`packages/worker`	Cloudflare Worker — ERC-8004 agent card + x402 `/task` endpoint
`packages/seller-agent`	Express server — accepts x402 + Blackbox payments, delivers AI report
`packages/buyer-agent`	Demo buyer — connects Blackbox MCP, pays seller, receives service
`packages/scripts`	Setup utilities — wallet generation, ERC-8004 registration, faucet

Environment Variables

CDP_API_KEY_ID=         # Coinbase Developer Platform API key
CDP_API_KEY_SECRET=     # CDP API secret (Ed25519 keypair, base64)
BUYER_PRIVATE_KEY=      # Generated by npm run wallets
BUYER_WALLET_ADDRESS=   # Derived from BUYER_PRIVATE_KEY
SELLER_PRIVATE_KEY=     # Generated by npm run wallets
SELLER_WALLET_ADDRESS=  # Derived from SELLER_PRIVATE_KEY
WALLET_PASSWORD=        # Password for Blackbox wallet encryption

Deployed Contracts

Contract	Address	Network
ERC-8004 IdentityRegistry	`0x8004A818BFB912233c491871b3d84c89A494BD9e`	Base Sepolia
ERC-8004 ReputationRegistry	`0x8004B663056A597Dffe9eCcC1965A193B7388713`	Base Sepolia
USDC	`0x036CbD53842c5426634e7929541eC2318f3dCF7e`	Base Sepolia

Built With

Blackbox Network — DKG threshold cryptography for private payments
ERC-8004 — on-chain agent identity and reputation
x402 — HTTP 402 payment protocol for AI agents
Coinbase CDP — faucet and wallet tooling
viem — TypeScript EVM client
Cloudflare Workers — serverless agent hosting
AgentCard — virtual Mastercard for agents (compatible via x402_fetch)

Name		Name	Last commit message	Last commit date
.claude		.claude
.github		.github
.playwright-mcp		.playwright-mcp
docs		docs
packages		packages
.env.example		.env.example
.gitignore		.gitignore
BOUNTIES.md		BOUNTIES.md
CONTEXT.md		CONTEXT.md
PLAN.md		PLAN.md
README.md		README.md
agent.json		agent.json
agent_log.json		agent_log.json
package.json		package.json

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AgentClear

The Problem

Three Layers, Not One

What It Does

Privacy Proof (live on Base Sepolia)

Architecture

Stack

Quick Start

Prerequisites

1. Install

2. Generate wallets

3. Fund the buyer

4. Start the seller

5. Run the demo

Payment Routing

AgentCard Compatibility

ERC-8004 Judging Criteria

Packages

Environment Variables

Deployed Contracts

Built With

About

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AgentClear

The Problem

Three Layers, Not One

What It Does

Privacy Proof (live on Base Sepolia)

Architecture

Stack

Quick Start

Prerequisites

1. Install

2. Generate wallets

3. Fund the buyer

4. Start the seller

5. Run the demo

Payment Routing

AgentCard Compatibility

ERC-8004 Judging Criteria

Packages

Environment Variables

Deployed Contracts

Built With

About

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Used by

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