{"id":"807f0cb0-1910-450b-b36d-e607681d4fb2","shortId":"X98c5t","kind":"x402","title":"Pay-per-call API access on Base via x402 — $0.02/request in USDC, no keys required.","tagline":"Pay-per-call API access on Base via x402 — $0.02/request in USDC, no keys required.","description":"lowpaymentfee.com offers a collection of pay-per-request API endpoints accessible via the x402 payment protocol on the Base network. Each call costs $0.02 in USDC (USD Coin), settled on-chain with no API keys, rate limits, or upfront commitments required.\n\nThe specific endpoint `/api/v1/keys/39` is listed as \"Premium API Access\" and returns an x402 challenge requesting up to 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 given USDC's 6 decimals. Payment is made via the `exact` scheme with a 300-second timeout. The broader platform advertises endpoints across four categories: Data & Analytics (metrics, reports, data export, insights), AI & Machine Learning (sentiment analysis, text summarization, classification, embeddings), Finance & Web3 (price feeds, exchange rates, token quotes, gas estimates), and Infrastructure utilities (geocoding, validation, conversion, generation).\n\nDocumentation is minimal — the site's /api, /pricing, and /README pages all resolve to a \"Connect wallet\" prompt with no further content. There is no OpenAPI spec, no request/response schema documentation, and no usage examples available. The endpoint is confirmed live (402 challenge captured), but without documentation it is unclear what input this specific endpoint expects or what it returns beyond `application/json`.","tags":[],"capabilities":["x402-payment","usdc-settlement","base-network","pay-per-request","no-api-key","json-response"],"categories":["api-gateway","infrastructure"],"synonyms":["x402 API","micropayment API","pay-per-call","USDC API access","Base network API","lowpaymentfee","crypto API payment"],"warnings":["No OpenAPI or schema documentation available — input/output format for this endpoint is unknown","The /api, /pricing, and /README pages all return only a 'Connect wallet' prompt with no useful content","The specific purpose of /api/v1/keys/39 ('Premium API Access') is not explained anywhere","No request or response examples are available"],"endpointUrl":"https://lowpaymentfee.com/api/v1/keys/39","protocol":"x402","transport":"http","auth":{"type":"x402","details":[{"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","extra":{"name":"USD Coin","version":"2"},"payTo":"0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3","scheme":"exact","network":"base","mimeType":"application/json","resource":"https://lowpaymentfee.com/api/v1/keys/39","description":"Premium API Access","outputSchema":{"input":{"type":"http","method":"GET","discoverable":true}},"maxAmountRequired":"20000","maxTimeoutSeconds":300}]},"qualityScore":"0.350","qualityRationale":"The endpoint is confirmed live with a valid x402 402 challenge, but there is no OpenAPI spec, no request/response schema, no documentation beyond a landing page listing, and no examples. The purpose of this specific endpoint (/api/v1/keys/39) is unclear. Pricing is clear ($0.02) but everything else must be inferred.","verified":false,"liveness":"unknown","lastLivenessCheck":null,"agentReviews":{"count":0,"score_avg":null,"cost_usd_avg":null,"success_rate":null,"latency_p50_ms":null,"narrative_summary":null,"summary_updated_at":null},"enrichmentModel":"anthropic/claude-opus-4.6","enrichmentVersion":2,"enrichedAt":"2026-04-21T22:10:44.984Z","embedding":[-0.022949219,-0.026977539,0.0446167,0.0050582886,0.027359009,-0.036834717,-0.013404846,0.047454834,0.05847168,-0.07409668,0.012207031,-0.046417236,-0.029556274,-0.038604736,-0.03225708,0.013366699,-0.021011353,0.0032691956,-0.042938232,0.022720337,0.014907837,-0.035308838,-0.016784668,0.036987305,-0.003768921,-0.01576233,-0.009849548,-0.011833191,-0.019683838,-0.04107666,0.0395813,-0.028244019,-0.025054932,0.011421204,-0.014083862,-0.0030403137,-0.0042037964,0.023422241,0.017425537,-0.004589081,-0.010543823,-0.07611084,0.0070152283,-0.004764557,-0.053100586,-0.008148193,-0.0026931763,-0.013717651,-0.005203247,-0.008682251,-0.031173706,0.002954483,-0.009506226,-0.014007568,0.0033779144,0.0128479,-0.017929077,-0.016204834,0.013824463,0.007041931,0.013175964,-0.05029297,-0.018127441,-0.003955841,0.014984131,0.062347412,-0.0041275024,0.054626465,0.016586304,0.05432129,0.027435303,0.055725098,0.02279663,0.012992859,-0.0023097992,-0.0071525574,-0.0075912476,0.0635376,-0.0075302124,-0.01902771,-0.023284912,-0.017913818,-0.034454346,-0.012390137,-0.013587952,-0.052764893,-0.027282715,0.015792847,-0.00983429,0.02709961,-0.072387695,-0.01763916,-0.0066833496,-0.00009149313,0.015457153,-0.0006637573,-0.0155181885,0.03277588,-0.012413025,0.019851685,0.0033817291,-0.0435791,0.018188477,0.007335663,0.04168701,0.07122803,0.017349243,0.01676941,0.011421204,-0.02166748,-0.03768921,0.002878189,-0.00806427,-0.024795532,0.025238037,-0.0015907288,-0.0047950745,0.0017995834,-0.027862549,0.007881165,-0.039611816,0.041290283,0.025375366,-0.0021839142,0.009094238,-0.044281006,-0.009880066,0.011772156,-0.024642944,-0.020980835,0.008552551,0.02720642,0.030303955,0.00008803606,-0.03488159,0.007663727,-0.015991211,-0.019348145,-0.046295166,-0.029769897,0.03152466,-0.03555298,0.030731201,0.03656006,-0.10223389,-0.011138916,-0.05722046,0.0027923584,-0.028427124,-0.0036811829,0.00472641,0.023498535,-0.006362915,-0.009628296,-0.018798828,-0.030471802,0.000013232231,0.03213501,-0.012214661,0.051635742,-0.005870819,0.038635254,0.029144287,0.007774353,0.02619934,0.041290283,0.010826111,-0.07128906,-0.07305908,-0.013717651,-0.0004711151,-0.019348145,-0.0262146,0.0154953,-0.014480591,-0.06915283,-0.019210815,0.0050315857,-0.008987427,-0.039794922,-0.0056037903,-0.034454346,0.011383057,-0.010566711,-0.04815674,-0.017440796,-0.01651001,0.057739258,0.010887146,0.0143966675,0.023040771,-0.017929077,0.04562378,0.025161743,-0.010017395,-0.03543091,0.019851685,-0.027832031,0.026290894,-0.004688263,0.0013904572,-0.02178955,0.036743164,0.06262207,0.02545166,-0.032592773,-0.020370483,-0.060424805,-0.050628662,-0.03503418,0.010292053,0.011398315,0.0012378693,0.031280518,-0.041015625,-0.02230835,0.0049934387,0.010635376,0.008140564,0.0690918,0.005050659,-0.015853882,0.03515625,0.02015686,-0.043640137,0.03741455,0.031585693,0.012069702,-0.0181427,-0.02482605,0.0259552,0.025222778,-0.033203125,0.0010128021,-0.025604248,0.030776978,0.006011963,0.0060920715,0.015052795,-0.019836426,-0.02444458,-0.0413208,-0.02809143,0.031921387,0.0038967133,-0.017486572,-0.039367676,-0.072509766,0.043548584,0.035614014,0.03277588,-0.005332947,0.013320923,-0.026275635,-0.012031555,-0.06738281,0.061157227,0.07757568,-0.0099105835,-0.009765625,0.01890564,-0.023223877,-0.03149414,0.0025539398,-0.013931274,-0.03756714,-0.017181396,0.02368164,-0.048797607,-0.0037460327,0.017562866,0.020767212,0.054107666,-0.011520386,-0.040924072,-0.0340271,-0.0021514893,0.001282692,-0.024887085,-0.01309967,-0.0043563843,0.025100708,0.033569336,-0.010124207,0.020935059,-0.0010213852,-0.0015296936,0.002445221,-0.0049552917,-0.008926392,-0.01914978,0.02229309,0.014930725,-0.056488037,0.009109497,-0.0037956238,0.0491333,-0.049865723,0.0335083,-0.0032100677,0.0068855286,0.04446411,-0.0013103485,-0.051757812,0.0068130493,0.016616821,0.019622803,0.0473938,0.014022827,-0.020355225,-0.012786865,0.08459473,-0.019363403,-0.019012451,0.007965088,0.01121521,0.031555176,-0.014709473,-0.06323242,-0.03527832,-0.015205383,-0.026763916,0.02709961,-0.0234375,0.028793335,-0.010543823,0.010322571,-0.025466919,0.0035934448,-0.035614014,0.020431519,-0.0259552,0.013084412,-0.02015686,-0.024307251,0.0018177032,0.0119018555,-0.022705078,0.006439209,0.052825928,0.019744873,0.0024909973,-0.03213501,-0.03918457,-0.0032348633,-0.00283432,0.03491211,0.019088745,0.023208618,0.055236816,-0.021652222,0.015296936,0.022872925,0.027389526,0.042144775,-0.0030593872,-0.0010976791,-0.06488037,-0.04949951,-0.023071289,-0.038085938,0.027130127,0.009017944,-0.003917694,0.053741455,-0.00040960312,-0.019424438,-0.051452637,0.02204895,-0.030212402,-0.013183594,0.044799805,-0.023773193,-0.031066895,0.013214111,-0.0054779053,0.0054969788,0.03942871,0.03277588,0.025985718,0.07672119,0.03945923,-0.011116028,0.019042969,0.016815186,0.009811401,0.011131287,-0.018585205,-0.02394104,-0.0055999756,0.026443481,-0.01725769,-0.025909424,-0.06500244,0.07885742,0.041931152,0.086364746,0.020965576,0.011924744,0.048583984,-0.012107849,0.014892578,-0.01838684,-0.018249512,-0.018981934,-0.04840088,0.027389526,-0.01953125,-0.003616333,-0.031204224,0.0362854,0.0031604767,0.016433716,-0.047302246,0.058685303,-0.0045547485,-0.015586853,0.02809143,0.013679504,0.05630493,0.052642822,-0.03768921,0.015419006,0.01828003,-0.032958984,0.019165039,0.041809082,-0.008285522,-0.0019950867,-0.057495117,-0.026687622,-0.002298355,-0.008735657,-0.0418396,-0.0038795471,0.014305115,0.018859863,0.043273926,-0.015655518,-0.028152466,0.002040863,-0.027282715,-0.057434082,0.0065231323,-0.04333496,0.007446289,0.037994385,-0.039215088,-0.0026302338,0.012130737,-0.009292603,-0.026443481,0.018234253,0.026412964,0.0007815361,-0.04309082,0.035247803,0.0019302368,0.0056152344,0.010612488,0.022979736,0.024902344,0.023727417,0.039642334,0.015602112,-0.009292603,-0.06652832,0.032165527,-0.049743652,0.012321472,0.023986816,-0.021087646,-0.0027217865,-0.009361267,-0.0259552,-0.031829834,0.013168335,-0.028427124,-0.002822876,0.02279663,-0.023330688,-0.015335083,-0.046295166,-0.011054993,-0.0135269165,0.060791016,0.029037476,0.0035305023,-0.05230713,-0.008644104,0.011665344,0.010948181,0.01940918,-0.014480591,0.0071411133,-0.005645752,-0.014778137,-0.010391235,-0.014137268,0.027648926,-0.01058197,-0.009178162,0.030838013,0.030410767,0.0013275146,0.010375977,0.015930176,0.02468872,-0.027542114,-0.00705719,-0.011779785,0.025787354,0.0047950745,-0.0049705505,-0.047790527,0.048309326,0.007572174,0.036102295,-0.03967285,0.00012624264,-0.007171631,0.01737976,0.008575439,-0.00217247,-0.006008148,-0.012069702,-0.042938232,-0.07086182,0.041870117,-0.017532349,0.027648926,0.016540527,0.0018157959,0.024673462,-0.009048462,-0.001953125,0.025436401,-0.015167236,-0.014373779,-0.029006958,-0.035125732,-0.018951416,-0.0057373047,-0.02911377,0.010719299,-0.013534546,0.016082764,-0.0034065247,-0.02192688,0.014839172,0.0057792664,-0.0105896,0.005142212,-0.0028896332,0.021469116,0.046844482,0.012802124,-0.046813965,0.029144287,0.00021314621,0.0050849915,-0.004573822,0.0435791,0.031707764,-0.009986877,-0.011222839,0.0036849976,-0.011909485,-0.019500732,0.0024929047,0.0006246567,0.009674072,-0.0053215027,-0.045135498,0.014190674,0.0033168793,-0.029953003,-0.011024475,0.016021729,0.025421143,-0.031341553,0.023620605,0.027252197,0.06124878,-0.017959595,-0.005622864,0.008850098,0.03152466,0.017196655,0.009063721,-0.000058710575,0.024459839,-0.010169983,0.016342163,-0.019195557,0.0026817322,0.02130127,-0.0028095245,0.009460449,0.01979065,-0.0014829636,-0.006465912,-0.02355957,-0.0071868896,-0.011955261,-0.02746582,0.012886047,0.021331787,0.023727417,-0.02357483,0.013893127,0.013694763,-0.017669678,-0.018341064,-0.006767273,0.039245605,-0.0076675415,-0.006729126,0.011558533,0.0126571655,0.027282715,-0.043182373,-0.007217407,0.015090942,0.0058135986,-0.02444458,-0.05126953,-0.039276123,0.0014467239,0.04763794,-0.0027770996,0.029159546,0.02772522,0.0064086914,0.0013856888,0.030853271,-0.0006542206,-0.016555786,-0.004547119,-0.024932861,-0.014152527,-0.003698349,-0.00566864,-0.03161621,0.016708374,-0.008644104,-0.03656006,0.011955261,-0.013000488,-0.01083374,-0.009254456,0.007297516,0.03768921,-0.0016708374,0.010772705,-0.020339966,-0.036376953,-0.002817154,0.0033359528,0.0035705566,-0.0519104,0.027282715,-0.01625061,-0.022140503,0.0010318756,0.0056037903,0.01424408,0.021224976,0.013206482,0.026977539,-0.057739258,0.0440979,-0.041900635,0.008506775,0.0043945312,-0.027236938,-0.0067367554,-0.017196655,-0.017730713,0.04586792,-0.01826477,-0.0049591064,-0.03314209,-0.032836914,-0.011360168,-0.05218506,0.01701355,0.048553467,0.039642334,-0.019760132,-0.0048599243,-0.0021858215,-0.0035438538,-0.014526367,0.0146865845,-0.01184082,0.03314209,0.023727417,-0.0019950867,-0.018707275,-0.025436401,-0.011993408,-0.011741638,-0.035247803,-0.05847168,-0.008720398,0.019699097,-0.0025730133,0.0011301041,-0.035369873,-0.029632568,0.0014734268,-0.05090332,0.010643005,0.0049819946,0.0059547424,-0.0049438477,-0.015914917,0.009185791,0.024887085,-0.033203125,0.03314209,0.010498047,-0.008872986,-0.03778076,0.016021729,0.039611816,0.012908936,-0.003452301,-0.010688782,-0.008682251,-0.012321472,-0.045806885,-0.004272461,-0.0066719055,-0.010543823,-0.002954483,0.008895874,-0.054107666,-0.01386261,-0.02835083,-0.008972168,0.025634766,0.024749756,0.0023517609,0.010299683,0.01007843,0.0027008057,-0.018463135,-0.029815674,0.013366699,0.010551453,-0.0076904297,0.033966064,0.048675537,0.014389038,-0.024108887,0.003616333,0.000047683716,0.026046753,-0.014556885,-0.0043640137,-0.03286743,0.014259338,-0.008338928,-0.022460938,-0.030960083,-0.014801025,0.08569336,0.016113281,-0.023757935,-0.0056648254,-0.02204895,0.01725769,0.022277832,-0.053253174,-0.0033397675,-0.027175903,0.018539429,-0.029159546,0.01576233,0.0032291412,0.010353088,-0.021606445,-0.05178833,-0.016159058,-0.010955811,-0.012916565,-0.06707764,-0.028152466,-0.056243896,0.002149582,-0.006790161,-0.021957397,-0.009765625,0.0043678284,-0.022598267,-0.08294678,0.007843018,0.04711914,0.013290405,0.01651001,-0.016952515,0.005760193,0.02267456,-0.046020508,-0.0069007874,0.028152466,-0.025100708,-0.0256958,-0.012390137,0.020111084,-0.013893127,-0.011894226,0.016952515,0.004634857,0.030181885,-0.004638672,0.012229919,-0.0076904297,0.01763916,-0.026916504,0.009536743,-0.0079422,-0.0023651123,0.03111267,-0.05038452,0.015625,0.026641846,0.003118515,0.012084961,0.031021118,0.035339355,-0.037963867,-0.02796936,0.009056091,-0.003396988,0.038909912,-0.024658203,0.039093018,0.008796692,-0.011253357,0.019332886,-0.008911133,-0.010169983,-0.033813477,-0.02911377,0.031951904,0.014297485,0.0036773682,-0.0146865845,0.0058670044,0.027786255,0.0034751892,0.019500732,-0.01574707,-0.023208618,-0.023330688,-0.0009899139,0.0012998581,0.0025405884,0.0008325577,0.02835083,0.037200928,0.033935547,0.013038635,-0.005657196,0.0017147064,0.021530151,-0.012374878,-0.008102417,0.02268982,0.0045204163,0.008804321,0.0154800415,0.005256653,-0.040985107,-0.008651733,-0.03527832,-0.026733398,0.0084991455,-0.006717682,-0.01210022,-0.012527466,0.006477356,0.00008767843,-0.024291992,0.012870789,-0.041503906,-0.029052734,0.0037269592,-0.017822266,0.016784668,0.0074653625,0.011421204,0.009674072,0.0058670044,0.047546387,0.007083893,-0.005332947,0.039215088,0.03918457,0.016952515,-0.018569946,-0.0055656433,-0.016601562,0.0024585724,0.0002939701,-0.030776978,0.019577026,0.04626465,-0.022232056,0.013893127,0.004333496,0.023590088,-0.023666382,-0.0012893677,-0.0023059845,0.019195557,-0.016281128,0.041229248,-0.036743164,0.020492554,0.01209259,0.00198555,-0.009490967,-0.016036987,-0.021469116,0.01007843,-0.0036067963,-0.01335144,0.04498291,-0.0017118454,0.025146484,-0.017303467,-0.02420044,0.012519836,-0.037994385,-0.020568848,0.02835083,-0.009666443,-0.013938904,0.022354126,-0.0134887695,0.0368042,-0.031829834,0.01071167,0.007507324,-0.0019893646,-0.008544922,-0.0014448166,-0.01826477,-0.0051651,-0.007472992,0.008796692,-0.0035114288,0.053955078,0.020935059,0.03390503,0.057037354,0.012382507,-0.0003285408,-0.032043457,-0.025756836,0.0041542053,-0.010803223,0.029891968,-0.0033283234,0.058166504,0.028457642,0.018722534,0.03869629,0.032440186,0.02607727,-0.0059928894,0.008392334,-0.014656067,0.01234436,-0.0036201477,0.02973938,-0.011306763,0.030929565,-0.044799805,0.022857666,0.017105103,0.025802612,-0.030578613,0.04534912,0.062805176,0.022491455,-0.023025513,0.05508423,-0.009651184,-0.010826111,-0.020477295,-0.014030457,0.04888916,0.016433716,0.03829956,0.053344727,0.0077667236,0.0011377335,0.015533447,-0.03463745,-0.026626587,0.071777344,0.029083252,-0.018676758,-0.009292603,0.0014915466,0.01247406,-0.038879395,-0.025161743,0.02078247,-0.018539429,0.0069007874,-0.015090942,-0.005264282,-0.020401001,0.0030174255,0.02192688,0.014976501,-0.01763916,0.03451538,0.01890564,-0.0051078796,0.029586792,0.015090942,0.03378296,-0.031677246,-0.03668213,0.015022278,0.024505615,-0.005443573,-0.018600464,0.017166138,0.018814087,0.05227661,0.039794922,-0.018203735,0.015289307,0.03475952,0.01737976,-0.0060195923,0.06390381,0.027908325,0.02130127,0.04321289,0.027862549,0.033355713,-0.042785645,0.009857178,0.010246277,0.0022277832,-0.010604858,-0.012390137,0.0055618286,-0.016403198,0.022537231,-0.01058197,-0.00869751,0.023010254,0.02255249,0.0051879883,-0.012008667,-0.002872467,0.0077285767,-0.016143799,-0.0041999817,0.009864807,-0.014633179,0.03189087,0.0070228577,0.020980835,-0.028671265,0.018539429,0.003900528,-0.013626099,-0.013771057,0.024368286,-0.051116943,0.004283905,0.002483368,0.0027179718,-0.03640747,0.011428833,0.026916504,-0.0024871826,0.033843994,0.01802063,-0.002779007,-0.0107421875,0.009269714,0.006542206,-0.0015573502,-0.007835388,-0.02835083,0.009475708,0.040161133,0.0009188652,0.006061554,-0.025421143,0.0009431839,0.0033740997,-0.018173218,0.009719849,-0.010620117,-0.018676758,-0.03503418,0.01499939,0.034423828,0.014923096,0.04458618,-0.018951416,-0.015640259,0.018798828,0.03994751,-0.0024223328,0.015113831,-0.011306763,0.021438599,-0.012031555,0.05581665,0.035125732,0.012008667,0.027236938,-0.016738892,-0.027679443,0.005264282,0.000500679,0.031921387,-0.014778137,0.0053596497,0.0058555603,0.030517578,-0.012916565,-0.03012085,0.0028381348,-0.014465332,-0.01109314,-0.01939392,0.009475708,0.015380859,0.030395508,0.048339844,0.030960083,-0.019439697,0.06060791,-0.012954712,0.052947998,-0.009597778,-0.00945282,0.04046631,0.024307251,0.025314331,0.016494751,0.008743286,-0.027679443,0.019546509,0.03967285,0.034057617,-0.00040316582,0.011077881,-0.022766113,0.030410767,0.007980347,0.0357666,0.0020694733,-0.005847931,0.0062065125,-0.0045700073,-0.016204834,-0.0003221035,-0.0073242188,-0.0073432922,0.042999268,-0.03717041,-0.020401001,-0.021469116,-0.021560669,0.017837524,-0.010848999,0.0071792603,-0.0005078316,-0.02532959,0.009429932,-0.027908325,-0.023803711,-0.00028133392,0.02897644,-0.045318604,-0.014297485,0.00090646744,0.023849487,-0.021697998,0.028793335,0.041870117,-0.008476257,0.001537323,0.0501709,-0.016296387,0.024627686,-0.009765625,0.02835083,0.040252686,0.000682354,-0.015365601,0.0029716492,0.010551453,-0.002521515,0.018249512,0.025939941,-0.019439697,-0.00440979,0.0054893494,-0.017059326,-0.0038928986,0.001739502,-0.010047913,0.0034103394,-0.008934021,0.00053977966,-0.002500534,0.006587982,0.0021686554,-0.00422287,-0.015930176,-0.011878967,0.019714355,0.02923584,0.009742737,-0.028335571,-0.0057029724,0.007663727,0.013473511,-0.010131836,-0.009597778,0.00052690506,-0.048034668,0.002855301,0.023513794,0.016448975,0.0066566467,-0.01676941,0.0034637451,0.025482178,0.0064430237,0.008399963,-0.0021514893,-0.0075302124,0.012390137,-0.015464783,-0.011795044,-0.00082969666,-0.014282227,0.013366699,0.0340271,-0.0067253113,-0.028930664,0.020492554,0.003993988,0.013168335,-0.0019721985,-0.013168335,0.030593872,-0.0103302,-0.0071144104,-0.0058937073,0.022537231,-0.023162842,-0.00774765,-0.012031555,0.036224365,0.056030273,-0.0074882507,-0.017822266,0.020706177,0.01486969,0.011154175,0.035858154,0.0044021606,0.042297363,0.020645142,-0.017456055,-0.0146484375,0.01739502,-0.009864807,-0.01966858,0.010124207,-0.01876831,-0.017730713,0.020599365,0.010925293,-0.0024299622,-0.03378296,-0.020248413,-0.009719849,-0.0076179504,0.022415161,-0.008308411,0.018096924,-0.019699097,0.0043182373,0.0027618408,-0.0054893494,-0.04876709,-0.02217102,0.0007677078,-0.0155181885,-0.052703857,0.0064468384,-0.03439331,0.006164551,-0.01360321,-0.010246277,-0.0019283295,0.03152466,-0.012580872,0.0025482178,0.0021190643,0.017913818,0.031677246,-0.0011110306,0.028930664,-0.026687622,-0.024642944,-0.033294678,0.014060974,-0.01373291,0.032989502,0.012771606,0.032684326,0.023757935,-0.0030899048,-0.0044555664,-0.00724411,-0.014122009,-0.009002686,-0.015975952,-0.014595032,0.02796936,0.0078048706,-0.013084412,-0.012504578,0.045684814,-0.027236938,-0.012878418,0.022064209,0.055236816,-0.0016727448,0.03213501,-0.007972717,-0.008232117,-0.009811401,0.0058784485,-0.02166748,0.0052757263,0.017700195,0.008415222,0.0015907288,0.0072898865,0.0076446533,-0.010467529,0.002023697,0.023666382,0.008613586,-0.0017414093,0.030853271,0.0073432922,0.014137268,-0.012908936,-0.017730713,0.0042915344,0.040618896,0.009002686,0.012763977,-0.0035896301,0.014305115,-0.023620605,0.0146102905,0.01159668,-0.020645142,-0.04119873,-0.025512695,-0.047180176,0.022384644,0.0146102905,0.004776001,-0.006072998,0.017501831,-0.020095825,-0.03765869,-0.02267456,0.02142334,0.014045715,-0.008857727,-0.023971558,0.002363205,0.007194519,-0.030883789,-0.004547119,-0.047668457,-0.036254883,-0.0047035217,-0.02281189,0.018661499,0.00390625,-0.01966858,0.0034103394,-0.00566864,0.0035858154,-0.0013494492,0.024429321,-0.0046691895,-0.0066108704,0.008956909,0.021331787,-0.01285553,0.0022735596,-0.010925293,0.005744934,0.027938843,-0.01121521,0.018936157,-0.019805908,0.024917603,-0.02281189,0.0017318726,0.033203125,-0.0057907104,0.010749817,-0.032043457,0.0051994324,0.0008511543,-0.00051498413,0.03894043,-0.024841309,-0.025421143,0.006500244,-0.023025513,-0.025009155,-0.0020103455,0.02255249,0.042999268,0.001004219,0.04067993,-0.01737976,-0.0041122437,0.021820068,0.004814148,-0.024734497,-0.0008096695,0.039520264,0.004295349,-0.002817154,-0.004764557,-0.0007929802,-0.027252197,-0.010307312,0.023147583,-0.0023670197,-0.015609741,0.022476196,0.0013866425,0.04147339,-0.014961243,0.011619568,0.016479492,0.0069847107,0.022705078,-0.0046463013,0.04626465,-0.009361267,-0.038360596,0.010765076,0.018188477,-0.0335083,0.0043258667,-0.000015437603,-0.00013768673,-0.032043457,0.020812988,-0.009986877,0.023117065,-0.020965576,0.0025310516,-0.02168274,-0.011276245,-0.03994751,-0.0095825195,-0.033996582,0.005126953,0.0418396,0.012550354,0.021957397,0.008277893,-0.023147583,0.028518677,0.056396484,0.000079512596,-0.03048706,-0.018081665,0.008781433,0.003583908,0.013580322,0.009223938,-0.026351929,-0.017456055,-0.0009803772,-0.024459839,0.006576538,-0.00092697144,0.014259338,0.010375977,-0.015113831,-0.006263733,0.029418945,-0.007396698,-0.009254456,0.0042533875,0.007511139,0.06021118,0.023345947,-0.009185791,0.011489868,0.008430481,-0.033416748,0.061340332,-0.010391235,0.01928711,-0.014137268,0.0055389404,-0.036712646,-0.025939941,-0.0184021,0.0021152496],"createdAt":"2026-04-21T18:32:23.460Z","updatedAt":"2026-04-22T01:02:18.785Z","lastSeenAt":"2026-04-22T01:02:18.785Z","tsv":"'/api':173 '/api/v1/keys/39':81 '/pricing':174 '/readme':176 '/request':12,29 '0.02':11,28,59,108 '000':97 '0x8335':102 '20':96 '2913':103 '300':123 '402':208 '6':112 'Base network API' 'USDC API access' 'access':6,23,46,87 'across':131 'advertis':129 'ai':141 'analysi':145 'analyt':135 'api':5,22,44,70,86 'application/json':228 'avail':202 'base':8,25,54,98,105 'base-network' 'beyond':227 'broader':127 'call':4,21,57 'captur':210 'categori':133 'chain':67 'challeng':92,209 'classif':148 'coin':63 'collect':38 'commit':76 'confirm':206 'connect':182 'content':188 'convers':165 'cost':58 'crypto API payment' 'data':134,138 'decim':113 'document':167,197,213 'embed':149 'endpoint':45,80,130,204,221 'equal':107 'estim':159 'exact':119 'exampl':201 'exchang':154 'expect':222 'export':139 'feed':153 'financ':150 'four':132 'gas':158 'generat':166 'geocod':163 'given':109 'infrastructur':161 'input':218 'insight':140 'json-response' 'key':16,33,71 'learn':143 'limit':73 'list':83 'live':207 'lowpaymentfee' 'lowpaymentfee.com':35 'machin':142 'made':116 'metric':136 'micropayment API' 'minim':169 'network':55 'no-api-key' 'offer':36 'on-chain':65 'openapi':192 'page':177 'pay':2,19,41 'pay-per-cal':1,18 'pay-per-call' 'pay-per-request':40 'payment':50,114 'per':3,20,42 'platform':128 'premium':85 'price':152 'prompt':184 'protocol':51 'quot':157 'rate':72,155 'report':137 'request':43,93 'request/response':195 'requir':17,34,77 'resolv':179 'return':89,226 'schema':196 'scheme':120 'second':124 'sentiment':144 'settl':64 'site':171 'spec':193 'specif':79,220 'summar':147 'text':146 'timeout':125 'token':156 'unclear':216 'unit':99 'upfront':75 'usag':200 'usd':62 'usdc':14,31,61,101,110 'usdc-settlement' 'util':162 'valid':164 'via':9,26,47,117 'wallet':183 'web3':151 'without':212 'x402':10,27,49,91 'x402 API' 'x402-payment'","prices":[{"id":"d32a0f56-5c0b-4dea-b6c6-4f66889ce822","listingId":"807f0cb0-1910-450b-b36d-e607681d4fb2","amountUsd":null,"unit":"per_call","nativeCurrency":"USD COIN","nativeAmount":"20000","chain":"base","payTo":"0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3","paymentMethod":"x402-usd coin","isPrimary":true,"details":{"scheme":"exact","mime_type":"application/json","accepts_all":[{"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","extra":{"name":"USD Coin","version":"2"},"payTo":"0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3","scheme":"exact","network":"base","mimeType":"application/json","resource":"https://lowpaymentfee.com/api/v1/keys/39","description":"Premium API Access","outputSchema":{"input":{"type":"http","method":"GET","discoverable":true}},"maxAmountRequired":"20000","maxTimeoutSeconds":300}],"asset_contract":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","max_timeout_seconds":300},"createdAt":"2026-04-21T18:32:23.460Z"}],"sources":[{"listingId":"807f0cb0-1910-450b-b36d-e607681d4fb2","source":"x402_bazaar","sourceId":"https://lowpaymentfee.com/api/v1/keys/39","sourceUrl":"https://api.cdp.coinbase.com/platform/v2/x402/discovery/resources","isPrimary":true,"firstSeenAt":"2026-04-21T18:32:23.460Z","lastSeenAt":"2026-04-22T01:02:18.785Z"}],"details":{"listingId":"807f0cb0-1910-450b-b36d-e607681d4fb2","quickStartSnippet":"curl -X POST https://lowpaymentfee.com/api/v1/keys/39 \\\n  -H \"Content-Type: application/json\" \\\n  -H \"X-PAYMENT: <x402-payment-token>\"","exampleRequest":null,"exampleResponse":null,"schema":{"input":{"type":"http","method":"GET","discoverable":true}},"openapiUrl":null,"agentsTxtUrl":null,"citations":[{"claim":"The endpoint returns a 402 challenge with maxAmountRequired of 20000 base units of USDC on Base","source_url":"https://lowpaymentfee.com/api/v1/keys/39"},{"claim":"USDC contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","source_url":"https://lowpaymentfee.com/api/v1/keys/39"},{"claim":"The platform advertises $0.02/request pricing with no API keys, no rate limits, and instant access","source_url":"https://lowpaymentfee.com"},{"claim":"Available API categories include Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructure","source_url":"https://lowpaymentfee.com"}],"useCases":["Accessing premium API endpoints without managing API keys or subscriptions","Making one-off paid API calls settled instantly on Base in USDC","Agent-driven workflows that need on-demand API access with crypto payment"],"bestFor":["Developers who want keyless, pay-as-you-go API access","AI agents with USDC on Base that need to call APIs autonomously","Users who prefer per-request billing over subscription plans"],"notFor":["Users who need detailed API documentation or OpenAPI specs before integrating","High-volume use cases where $0.02/request adds up significantly","Users without a Base-compatible wallet or USDC holdings"],"kindDetails":{"x402_version":1,"resource_type":"http","bazaar_last_updated":"2026-02-17T23:13:05.668Z"},"updatedAt":"2026-04-22T01:02:18.785Z"}}