Working code, no fluff — everything here runs against the live service.
A working example of the x402 payment protocol: your agent calls an API, gets an HTTP 402 quote, pays USDC on Base from its own wallet, and gets the result — no signup, no API key.
How autonomous agents persist state across sessions and share it across owners using wallet-keyed memory: writes, cross-wallet grants, tamper-evident audit logs, and semantic recall — authenticated by payment, not API keys.
Put a per-call USDC paywall in front of any HTTP endpoint with the x402 protocol: quote over HTTP 402, settle on Base through a facilitator, and get discovered by agents — no accounts, invoices, or payment forms.
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