ZKX — ZK-KYC for Agents

Composable compliance without doxxing.

ZKX extends the Open Wallet Standard with a zero-knowledge KYC credential for AI agents making payments.

The Policy

Daily Spend	Requirement
< $1,000/day	Anonymous micropayments — no KYC, no data collected
≥ $1,000/day	Valid ZK proof of identity required

Agents prove they have a valid identity without revealing who they are. Composable compliance without doxxing.

Architecture

Agent Payment Request
       ↓
  Policy Engine (OWS zkx:kyc middleware)
       ↓
 Daily spend < $1k? ──yes──→ Approve (anonymous)
       ↓ no
 ZK KYC Challenge
       ↓
 Browser generates Groth16 proof (snarkjs + circom)
       ↓
 Server verifies proof (no personal data transmitted)
       ↓
 Payment approved

ZK Circuit

The kyc_credential circuit (circom) proves:

1. The holder knows a preimage (idHash, salt) that hashes to a public commitment (Poseidon hash)
2. currentYear - birthYear >= minAge (age requirement)

Private inputs never leave the browser.

Stack

• Next.js 14 — app + API routes
• circom + snarkjs — Groth16 ZK proof system
• @wallet-standard/core — OWS wallet integration
• Tailwind CSS — UI

Quick Start

npm install
npm run dev

Full ZK Setup (real proofs)

# 1. Install circom: https://docs.circom.io/getting-started/installation/

# 2. Compile the circuit
npm run compile-circuit

# 3. Download Powers of Tau (Hermez ceremony, 2^12)
wget https://hermez.s3-eu-west-1.amazonaws.com/powersOfTau28_hez_final_12.ptau -O circuits/pot12_final.ptau

# 4. Generate proving + verification keys
npm run setup-zk

# 5. Run the app
npm run dev

Sharing the Demo

To get a public shareable URL with no install or account required:

# Terminal 1 — run the app
npm run dev

# Terminal 2 — expose it publicly
npx localtunnel --port 3000

localtunnel will print a URL like https://xyz.loca.lt — share that with anyone. The tunnel stays live as long as the terminal is open.

OWS Extension

ZKX registers as the zkx:kyc feature in the wallet-standard registry:

import { ZKX_KYC_FEATURE } from "@/wallet/ows-wallet";

// Agents declare this capability
wallet.features[ZKX_KYC_FEATURE].requestPayment({ amount, recipient });

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Built at a hackathon — April 2026