{"openapi":"3.1.0","info":{"title":"Open Topo Data","version":"1.0.0","description":"Elevation lookups from Open Topo Data across public DEM datasets: SRTM 90m, ASTER 30m, and the ETOPO1 bathymetry model. Machine-payable per request.","contact":{"email":"contact@meshgateway.co"},"x-guidance":"Every path is payable per request over HTTP 402 in USDG on eip155:4663. GET or POST without credentials to receive the challenge (WWW-Authenticate Payment header, plus the x402 payment-required header). Sign PermitWitnessTransferFrom for the advertised offer (spender is the canonical x402ExactPermit2Proxy) and retry with the payment-signature header. Buyers only need USDG: a one-time sponsored Permit2 approval is available at POST /api/gas/sponsor {\"address\"}."},"x-service-info":{"description":"Elevation lookups from Open Topo Data across public DEM datasets: SRTM 90m, ASTER 30m, and the ETOPO1 bathymetry model. Machine-payable per request."},"paths":{"/aster30m":{"get":{"summary":"Elevation from the ASTER GDEM. Pass ?locations=27.98,86.92.","responses":{"200":{"description":"Successful response"},"402":{"description":"Payment Required"}},"x-payment-info":{"price":{"mode":"fixed","currency":"USD","amount":"0.002000"},"protocols":[{"mpp":{"method":"evm","intent":"charge","currency":"0x5fc5360D0400a0Fd4f2af552ADD042D716F1d168"}},{"x402":{}}],"amount":"2000","currency":"0x5fc5360D0400a0Fd4f2af552ADD042D716F1d168","description":"Open Topo Data: ASTER 30m elevation","intent":"charge","method":"evm","recipient":"0xbB818E97E2260904B1D502E154488392ba2Ab5C9","scheme":"exact","network":"eip155:4663","extra":{"assetTransferMethod":"permit2","spender":"0x402085c248EeA27D92E8b30b2C58ed07f9E20001","name":"USDG"}}}},"/etopo1":{"get":{"summary":"Land elevation and ocean depth. Pass ?locations=40,-30.","responses":{"200":{"description":"Successful response"},"402":{"description":"Payment Required"}},"x-payment-info":{"price":{"mode":"fixed","currency":"USD","amount":"0.002000"},"protocols":[{"mpp":{"method":"evm","intent":"charge","currency":"0x5fc5360D0400a0Fd4f2af552ADD042D716F1d168"}},{"x402":{}}],"amount":"2000","currency":"0x5fc5360D0400a0Fd4f2af552ADD042D716F1d168","description":"Open Topo Data: ETOPO1 bathymetry","intent":"charge","method":"evm","recipient":"0xbB818E97E2260904B1D502E154488392ba2Ab5C9","scheme":"exact","network":"eip155:4663","extra":{"assetTransferMethod":"permit2","spender":"0x402085c248EeA27D92E8b30b2C58ed07f9E20001","name":"USDG"}}}},"/srtm90m":{"get":{"summary":"Elevation from NASA SRTM. Pass ?locations=27.98,86.92 or a pipe-separated list.","responses":{"200":{"description":"Successful response"},"402":{"description":"Payment Required"}},"x-payment-info":{"price":{"mode":"fixed","currency":"USD","amount":"0.002000"},"protocols":[{"mpp":{"method":"evm","intent":"charge","currency":"0x5fc5360D0400a0Fd4f2af552ADD042D716F1d168"}},{"x402":{}}],"amount":"2000","currency":"0x5fc5360D0400a0Fd4f2af552ADD042D716F1d168","description":"Open Topo Data: SRTM 90m elevation","intent":"charge","method":"evm","recipient":"0xbB818E97E2260904B1D502E154488392ba2Ab5C9","scheme":"exact","network":"eip155:4663","extra":{"assetTransferMethod":"permit2","spender":"0x402085c248EeA27D92E8b30b2C58ed07f9E20001","name":"USDG"}}}}}}