PromptPay
Pay-per-prompt AI marketplace: connect your wallet, grant one spend permission, then pay only for the prompts you send via automatic on-chain micro-payments.
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Descripción
PromptPay is a pay-per-prompt AI marketplace that replaces subscriptions and API keys with a single wallet connection.
Users grant a one-time ERC-7715 spend permission, then send prompts that are paid for automatically via x402 on-chain micro-payments settling fractions of a cent per request in the background, with no transaction to sign each time.
Prompts run on Venice AI for privacy-first inference, and payments are relayed gaslessly through the 1Shot permissionless relayer on Base. The result is a frictionless, usage-based way to access AI: pay only for what you actually use, no commitments, no key management, no recurring fees.
Progreso del hackathon
We designed and built PromptPay end-to-end during the hackathon, going from concept to a working pay-per-prompt AI marketplace.
Architecture & planning: Mapped the full system: wallet, ERC-7715 spend permission, x402 micro-payment , Venice AI inference, with the 1Shot relayer handling gasless settlement on Base Sepolia.
Frontend: Built the Next.js 14 app: landing page, prompt interface, wallet connect, a permission gate for granting the one-time spend allowance, result panel, and transaction history.
Payments; Implemented the x402 client/server flow so a protected API returns
402 Payment Required, the client auto-settles the micro-payment, and the prompt proceeds, no per-prompt signing.Permissions: Integrated ERC-7715 spend permissions via wagmi + MetaMask SDK so users grant a budget once.
AI integration: Wired up the Venice AI API for privacy-first, OpenAI-compatible inference behind the paid endpoint.
Relayer: Connected the 1Shot permissionless relayer (EIP-7710) for gasless, USDC-paid transactions.
By the end we had a functional flow: connect wallet, grant permission once, prompt and auto-pay per request.
Estado de recaudación de fondos
None