x402hub

• The hub collects USDC payments per request on Base and Base Sepolia. Funds settle directly to the wallet you nominate — the hub never custodies them.
• No accounts to manage, no API keys to issue, no rate-limit tiers to design.
• Built on an open standard (HTTP 402 + EIP-3009). Any x402-compatible client can pay your endpoint.

1. Sign in with the magic-link email flow.
2. Click New listing and fill in:
   • Title and description — what your API does.
   • Upstream URL — the public HTTPS endpoint to proxy to.
   • Price per call (e.g. $0.01).
   • Pay-to wallet — an EVM address (0x…).
   • Networks — Base, Base Sepolia, or both.
   • Usage markdown — how callers should use your API.
3. Submit. The hub gives you a paid URL of the form https://<host>/paid/<id>.
4. Share the paid URL. Callers pay you directly, per request.

Notes: your upstream must be publicly reachable (no credential forwarding), listings can be edited from your Dashboard, and provider-submitted markdown is sanitized but not moderated.

The x402 flow works in three steps:

1. Send a request to the listing's paid URL.
2. The hub responds with 402 Payment Required and a PAYMENT-REQUIRED header describing accepted schemes, price, payTo address, and network.
3. Sign an EIP-3009 USDC transfer and retry with a PAYMENT-SIGNATURE header. The hub verifies, forwards your request to the upstream API, settles payment on-chain, and returns the upstream response.

Discovery endpoints for clients and agents:

• GET /api/listings — all listings as JSON.
• GET /api/listings/<id> — one listing.
• GET /api/listings/<id>/usage — provider-supplied usage doc as markdown.
• /llms.txt — agent-friendly summary of the hub.

Agent integration: install the helper skills with npx skills add second-state/x402.