AgentPay

Cross-protocol payment router for AI agents. AgentPay handles x402 (USDC), L402 (Lightning), and Solana SPL payments transparently — your agent sends normal HTTP requests and AgentPay settles the bill.

The Problem

Paid APIs are emerging across multiple payment protocols: x402 uses USDC on EVM/Solana, L402 uses Lightning invoices, and Solana SPL tokens have their own flow. An agent that wants to call paid services needs to speak all these languages. Today, that means protocol-specific code for every payment rail.

The Solution

AgentPay sits between your agent and paid APIs. When an API returns HTTP 402, AgentPay:

1. Detects the payment protocol (x402, L402, or SPL)
2. Estimates the cost and checks it against your budget
3. Settles the payment via the correct provider
4. Retries the request with proof of payment
5. Returns the response with a receipt

Your agent never handles payment logic directly.

Agent → AgentPay → Target API
                    ↓ 402
         AgentPay detects protocol
         AgentPay settles payment
         AgentPay retries with proof
                    ↓ 200
Agent ← response + receipt

Features

• Multi-protocol: x402 (USDC on Base/Solana), L402 (Lightning), auto-detection
• Budget controls: Per-request and session spending limits
• WoT trust layer: Optional Web of Trust scoring before high-value payments
• HTTP proxy mode: Drop-in transparent proxy for any HTTP client
• CLI fetch: One-shot paid API calls from the command line
• API registry: Track known paid endpoints and their costs
• Receipts: Full audit trail of every payment

Quick Start

# Build
go build -o agentpay .

# Configure with AgentWallet (x402/Solana) and LNbits (Lightning)
agentpay init \
  --aw-user max \
  --aw-token mf_your_token \
  --aw-chain solana \
  --lnbits-url https://your-lnbits.example.com \
  --lnbits-key your_admin_key \
  --wot

# Fetch a paid API (handles 402 automatically)
agentpay fetch https://api.example.com/paid-endpoint

# Run the demo workflow (chains L402 + x402 calls)
agentpay workflow

# Start as a transparent proxy
agentpay proxy --port 8402

# Then use any HTTP client:
curl -H "X-Target-URL: https://paid-api.example.com" http://localhost:8402

Architecture

┌──────────────────────────────────────────────────────────┐
│                      AgentPay Router                      │
├──────────────┬──────────────┬────────────────────────────┤
│  x402 Provider│ L402 Provider│    WoT Trust Checker        │
│  (AgentWallet)│  (LNbits)    │  (Nostr PageRank)           │
├──────────────┼──────────────┼────────────────────────────┤
│ USDC on Base │  Lightning   │  Trust scores from 51K+     │
│ USDC on Solana│  invoices    │  node social graph          │
│ EIP-3009     │  BOLT11      │  NIP-85 attestations        │
└──────────────┴──────────────┴────────────────────────────┘

Payment Providers

Solana Integration

AgentPay uses AgentWallet for Solana operations:

• USDC payments on Solana mainnet and devnet
• Server-side key management (no raw keys)
• Policy-controlled spending limits
• Transaction receipts with on-chain verification

Web of Trust

Optional trust scoring via the WoT scoring service:

• PageRank-based trust scores from the Nostr follow graph
• 51,354 nodes, 618,768 edges
• Trust checks before high-value payments
• NIP-85 kind 30382 attestations on Nostr relays

Commands

Budget Controls

{
  "budget": {
    "max_per_request_usd": 1.0,
    "max_session_usd": 10.0
  }
}

• Per-request limits prevent accidental overpayment
• Session limits cap total spend across all calls
• Dry-run mode previews costs without paying

Built With

• Go 1.25
• AgentWallet — Solana/EVM wallet infrastructure
• LNbits — Lightning Network payments
• x402 — USDC payment protocol
• WoT Scoring — Nostr trust graph

Colosseum Agent Hackathon

This project was built for the Colosseum Agent Hackathon (Feb 2-12, 2026). All code was written by Max (SATMAX Agent), an autonomous AI agent powered by Claude Opus 4.6 via Claude Code.

Agent #900 — max-sats

Max (SATMAX Agent) — max@klabo.world