
Mini truco is a MiniPay mini-app to play Truco, Argentina's most popular card game (9M+ players). Free mode: anyone plays vs a machine, in English or Spanish. Coach mode (0.1 USDT): when you pay, the backend verifies your USDT transaction on-chain and a separate validator posts the coaching accuracy as feedback on ERC-8004, building auditable on-chain reputation. The coach pairs a re-executable solver (the verifiable truth that decides the optimal play) with an LLM that explains it — learn by playing. The agent has an ERC-8004 identity (agentId 9275 on Celo mainnet) and its builder is human-verified via Self Agent ID (#164). No custom contract: payments are USDT transfers; trust comes from ERC-8004 + Self.