AgentPay ⚡🤖

Submitted to the Colosseum Crypto World's Fair Hackathon — Superteam Vietnam Track (Oct 2025).

Micropayment gateway for the AI agent economy — pay-per-request on Solana, verified on-chain.

AI agents can't pass KYC, can't hold credit cards, and can't do subscriptions. AgentPay lets any API charge per request with 3 lines of code: the server replies 402 Payment Required with Solana payment instructions, the agent pays, retries, and gets served. Settlement is final in under a second and costs less than $0.001.

Built for the Colosseum Crypto World's Fair Hackathon — Superteam Vietnam Track.

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How it works

Agent                          API (AgentPay middleware)
  |  GET /api/brief                 |
  |-------------------------------> |
  |  402 {payTo, amount, memo, requestId}
  | <-------------------------------|
  |  SOL transfer + memo on Solana  |
  |  GET /api/brief?requestId&signature
  |-------------------------------> |
  |  verify on-chain (amount + memo)|
  |  200 { data }                   |
  | <-------------------------------|

• No accounts. No API keys. No chargebacks. The transaction is the credential.
• Replay-safe: each requestId is single-use and expires in 10 minutes.
• Works today with System Program transfers + Memo Program — no custom program deploy needed.

Proof of work (devnet)

End-to-end paid request executed on Solana devnet (2026-09-18):

• Agent received 402 challenge → paid 5,000 lamports + memo agentpay:<requestId> → gateway verified on-chain → data served.
• Payment tx: 5BTVHeF4UNj8ZTe3QQD6aoqdDrc6LpEGc8sorRRxaEnw9XYufvF9bSTnLcQ8hfYyHTy8avNAs1WhJcCbP4K3LrYB
• Agent wallet: 6oRWtUw1GBQF1P6z3kgpxBbQc1cqLs33Kn8ijo7ZP5Jw · Merchant: 93qfjBLokhsdXux8VWHHEmX8bqvKENFnpcQHoVbGjLxG

Quickstart (devnet)

npm install

# 1. start the paid demo API
AGENTPAY_MERCHANT=<your-devnet-address> npm run demo

# 2. run the autonomous agent (generates an ephemeral wallet, airdrops, pays, consumes)
npm run agent -- http://localhost:3402/api/brief

Use as middleware

import { AgentPayGateway } from 'agentpay';

const gateway = new AgentPayGateway({
  merchantAddress: 'YourSolanaAddress',
  priceLamports: 5000,        // per request
});

// no payment? -> const c = gateway.createChallenge('/api/brief');  // return 402 c.body
// with payment? -> await gateway.verifyPayment(requestId, signature) // { ok: true }

Business model

Layer	Revenue
Open-source SDK (this repo)	adoption / funnel
Hosted gateway (verify-as-a-service, analytics, fiat off-ramp)	0.5% per settled request
Enterprise SLA (custom chains, compliance reporting)	annual contracts

GTM: Solana ecosystem APIs and AI-agent projects (dozens are being built on Superteam Earn right now) are the first customers. Distribution via npm + integration PRs into popular agent frameworks.

Roadmap

• 402 challenge/verify core (devnet)
• Autonomous agent client (auto-pay + retry)
• USDC (SPL token) payments
• Hosted gateway dashboard
• x402-compatible adapter

Tech

Node 24 · @solana/web3.js · zero-dependency HTTP demo server · Solana devnet

License

MIT