{"x402_version":1,"environment":"production","asset":"USDC","decimals":6,"network":{"name":"base","chain_id":8453},"token_address":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","authorization_type":"TransferWithAuthorization (EIP-3009)","signature_scheme":"EIP-712","eip712_domain":{"name":"USD Coin","version":"2","chainId":8453,"verifyingContract":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913"},"challenge_ttl_seconds":300,"custody":"none","recipient":"0xc59c85e661d34084a7769f955d17fd38254a6235","price_minor":"dynamic per-tool (floor–x5); the 402 challenge body is authoritative","pricing_mode":"dynamic-dutch","pricing_rule":"idle decay to per-tool floor (tau=1800s); settled sales bump the price x1.5 (capped); live prices on GET /health","free_tier":"20 calls/day per client","settlement":"facilitator (gas-sponsored, on-chain, non-custodial)","notes":"The 402 challenge body is authoritative for recipient, amount, chain, nonce. Payer->seller direct; the rail never holds funds."}