{"id":"9136e310-81ab-422b-8d77-c8f52c834d4b","shortId":"wX2ELE","kind":"x402","title":"x402-gated API key endpoint on Base, paying $0.02 in USDC per request.","tagline":"x402-gated API key endpoint on Base, paying $0.02 in USDC per request.","description":"This endpoint at lowpaymentfee.com provides \"Premium API Access\" via the x402 payment protocol. It is one of many endpoints offered by the lowpaymentfee.com platform, which hosts a variety of pay-per-request APIs spanning data & analytics, AI & machine learning, finance & Web3, and infrastructure utilities — all priced at $0.02 per call settled in USDC on the Base network.\n\nThe specific resource `/api/v1/apikeys/27` appears to be an API-key provisioning or management endpoint. The x402 challenge confirms it is live, accepting POST requests, and requires an exact payment of 20,000 base units of USDC (0x8335…2913 on Base, 6 decimals → $0.02) to the payTo address 0x1A2B…85F3. The payment timeout is 300 seconds. No OpenAPI schema, detailed documentation, or example request/response bodies were found in the crawl — the docs, pricing, API, and README pages all returned only a \"Connect wallet\" prompt with no substantive content.\n\nThe platform advertises no API keys required, no rate limits, and instant access for all its endpoints. However, the lack of documentation makes it difficult to know what request body this particular endpoint expects or what it returns. Users should treat this as a lightly-documented, experimental service.","tags":[],"capabilities":["x402-payment","usdc-base","pay-per-request","api-key-provisioning","post-endpoint"],"categories":["infrastructure","api-management"],"synonyms":["x402 API key","pay-per-call API","USDC micropayment API","Base network API","lowpaymentfee","premium API access","crypto-paid API"],"warnings":["No API documentation available — docs, pricing, API, and README pages all return only a 'Connect wallet' prompt with no content.","The exact purpose and expected request/response format of /api/v1/apikeys/27 is undocumented and must be inferred from the endpoint name alone.","No OpenAPI or JSON schema provided for request or response bodies.","Platform appears experimental with minimal public information."],"endpointUrl":"https://lowpaymentfee.com/api/v1/apikeys/27","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/apikeys/27","description":"Premium API Access","outputSchema":{"input":{"type":"http","method":"GET","discoverable":true}},"maxAmountRequired":"20000","maxTimeoutSeconds":300}]},"qualityScore":"0.300","qualityRationale":"The endpoint is live and returns a valid x402 challenge with clear pricing. However, there is no OpenAPI schema, no documentation beyond a landing page listing, no example requests or responses, and the docs/pricing/README pages are all empty (wallet-connect only). The purpose of this specific endpoint (apikeys/27) is unclear.","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":"2026-04-19T15:15:47.772Z","embedding":[-0.007637024,-0.024154663,0.035003662,0.007534027,0.017715454,-0.04055786,-0.019821167,0.03540039,0.06878662,-0.08001709,0.019256592,-0.038513184,-0.05166626,-0.044128418,-0.03036499,0.00019001961,-0.035583496,0.0016298294,-0.05706787,0.02760315,0.04562378,-0.028869629,-0.00075769424,0.054901123,-0.0010023117,-0.010185242,-0.0052948,-0.025817871,-0.01159668,-0.037475586,0.038360596,-0.027313232,-0.02897644,0.026031494,-0.02305603,0.0012550354,-0.0065193176,0.040222168,0.028167725,-0.005455017,-0.0074310303,-0.058258057,0.008407593,0.012374878,-0.028121948,0.0014286041,-0.012580872,-0.03353882,-0.024520874,0.0032596588,-0.027374268,0.004119873,-0.0096588135,0.013397217,0.014030457,0.021957397,-0.0078125,-0.026870728,0.0006785393,0.02507019,0.02279663,-0.050964355,-0.0043945312,0.011276245,0.015731812,0.048461914,-0.0053710938,0.050994873,0.012001038,0.046813965,0.025863647,0.070495605,0.027648926,0.025054932,-0.0032577515,0.0025234222,-0.00491333,0.047546387,-0.004295349,-0.021194458,-0.019348145,-0.013153076,-0.044708252,-0.020523071,-0.022201538,-0.06970215,-0.037078857,0.0024681091,-0.011177063,0.02470398,-0.08477783,-0.012687683,0.0049362183,0.03579712,0.010574341,-0.0055503845,-0.03036499,0.009361267,-0.0010271072,0.029586792,0.019485474,-0.03475952,0.016448975,0.020462036,0.047088623,0.048553467,0.015914917,0.023651123,0.005203247,-0.026748657,-0.032348633,-0.0032463074,-0.0181427,-0.008087158,0.024169922,-0.012374878,-0.013008118,0.022949219,-0.0138168335,0.008171082,-0.04824829,0.04949951,0.027496338,-0.030288696,-0.004085541,-0.059143066,-0.0038833618,0.0039367676,-0.03555298,-0.01828003,0.010765076,0.002620697,0.009819031,0.0027675629,-0.024765015,0.012817383,-0.017578125,-0.026107788,-0.054626465,-0.012481689,0.02897644,-0.03741455,0.025863647,0.03729248,-0.103637695,-0.010513306,-0.05609131,0.0073394775,-0.023208618,-0.015975952,0.01838684,0.0067977905,0.0017700195,-0.0013494492,-0.0049819946,-0.021514893,-0.011642456,0.014022827,-0.008308411,0.040740967,-0.024719238,0.041046143,0.03314209,0.018188477,0.020126343,0.048675537,0.0042648315,-0.070129395,-0.081726074,-0.02734375,-0.002462387,-0.012840271,-0.032165527,0.020446777,-0.013542175,-0.058776855,-0.034942627,-0.0032615662,-0.010169983,-0.048187256,-0.013244629,-0.020111084,0.009605408,-0.001282692,-0.052947998,-0.009399414,-0.027038574,0.051635742,0.017807007,0.0022697449,0.024475098,-0.016143799,0.046447754,0.015533447,0.0047035217,-0.037841797,0.017288208,-0.039886475,0.042663574,0.019363403,0.006225586,-0.032684326,0.02746582,0.049438477,0.02998352,-0.015914917,0.012672424,-0.038208008,-0.02923584,-0.026275635,0.008644104,0.008102417,-0.00047898293,0.009780884,-0.030090332,-0.019424438,0.0013418198,0.0050582886,0.018005371,0.061462402,-0.008728027,-0.00299263,0.026138306,0.039886475,-0.033996582,0.051483154,0.031341553,0.019958496,-0.026748657,-0.018737793,0.028167725,0.038085938,-0.027160645,0.0029563904,-0.02670288,0.013435364,-0.0040397644,0.008911133,0.023391724,-0.01247406,-0.013694763,-0.0413208,-0.021011353,0.031280518,-0.010513306,-0.0079574585,-0.052764893,-0.06591797,0.035308838,0.04107666,0.027191162,-0.016052246,0.010887146,-0.034851074,-0.005302429,-0.06439209,0.049041748,0.07397461,-0.010009766,-0.019866943,0.026290894,-0.018722534,-0.027679443,-0.013557434,0.00005722046,-0.025985718,-0.011680603,0.023910522,-0.04135132,0.0115737915,0.011833191,0.023132324,0.055114746,-0.020080566,-0.023101807,-0.012939453,0.011070251,0.0065078735,-0.04711914,-0.010749817,0.019973755,0.008422852,0.043029785,-0.0077590942,0.02017212,-0.00034165382,0.0070152283,-0.0062294006,-0.026123047,-0.019073486,-0.02458191,0.024658203,0.0070114136,-0.049438477,0.025558472,0.0016460419,0.027862549,-0.043701172,0.02394104,-0.0073776245,0.016021729,0.037628174,-0.011131287,-0.06524658,-0.013786316,0.031280518,0.04043579,0.05596924,0.023529053,0.007911682,0.0005545616,0.077941895,-0.01977539,-0.010322571,0.006389618,0.03338623,0.036102295,-0.015975952,-0.07397461,-0.03540039,-0.022125244,-0.021728516,0.016647339,-0.026123047,0.03213501,-0.0058288574,0.013557434,-0.009819031,0.001701355,-0.028823853,0.020339966,-0.02961731,0.01398468,-0.015670776,-0.030426025,-0.006752014,0.03439331,-0.008308411,0.014877319,0.036865234,0.006996155,-0.0061073303,-0.012123108,-0.0035991669,-0.027648926,0.015068054,0.04397583,0.019500732,0.005382538,0.04144287,-0.024093628,0.01638794,0.014190674,-0.00083208084,0.031173706,-0.0054016113,0.008743286,-0.054595947,-0.054260254,-0.0037021637,-0.01991272,0.031707764,-0.0007505417,-0.0019893646,0.047454834,-0.009651184,-0.009307861,-0.06414795,0.029464722,-0.033203125,-0.004196167,0.029342651,-0.021194458,-0.029083252,0.0018396378,0.004283905,0.02381897,0.033477783,0.025360107,0.012496948,0.0713501,0.03692627,0.019561768,0.008514404,0.031341553,0.028411865,-0.018005371,-0.01727295,-0.024215698,0.005317688,0.02432251,-0.03515625,-0.023834229,-0.07623291,0.070739746,0.04458618,0.07574463,0.01625061,0.00048971176,0.05935669,-0.026397705,0.002840042,-0.017089844,-0.0021858215,-0.02798462,-0.04776001,0.025527954,-0.02015686,0.007827759,-0.040008545,0.035003662,0.017440796,0.007881165,-0.056762695,0.06365967,0.015014648,-0.006958008,0.00995636,0.0027770996,0.04034424,0.04901123,-0.03829956,-0.009025574,0.0099105835,-0.02482605,0.006855011,0.035247803,-0.0034236908,-0.01474762,-0.06677246,-0.029022217,-0.00932312,-0.017578125,-0.07220459,-0.0065574646,0.01159668,0.012649536,0.021255493,-0.040161133,-0.03036499,-0.0012340546,-0.0178833,-0.05319214,0.018493652,-0.045837402,0.015899658,0.042175293,-0.028869629,-0.012306213,0.012191772,0.000026404858,-0.014503479,0.023071289,0.01361084,0.008575439,-0.039367676,0.02619934,-0.0014619827,0.0023498535,0.012359619,0.016098022,0.030807495,0.01889038,0.040252686,0.025161743,-0.010719299,-0.042236328,0.032104492,-0.057495117,0.01361084,0.015640259,-0.032196045,-0.0076828003,-0.01247406,-0.03387451,-0.020904541,0.024459839,-0.022613525,0.01424408,0.04510498,-0.05050659,-0.018173218,-0.056854248,-0.030914307,-0.0042877197,0.05960083,0.03729248,0.0154418945,-0.049346924,-0.0064048767,0.013244629,0.0005426407,0.0034732819,-0.014419556,-0.009162903,-0.008514404,-0.014190674,-0.015975952,-0.01424408,0.0446167,-0.0043411255,-0.01322937,0.011932373,0.011421204,0.00071525574,0.025344849,0.011955261,0.023757935,-0.025756836,-0.0051498413,-0.016845703,0.015838623,0.0048675537,-0.015640259,-0.047332764,0.04043579,0.0061454773,0.040740967,-0.03463745,0.002779007,0.011489868,0.02558899,0.010025024,0.00012528896,0.0018529892,0.0073127747,-0.0524292,-0.08453369,0.034057617,-0.015510559,0.032836914,0.016311646,0.014137268,0.038238525,-0.02281189,-0.0023612976,0.025619507,-0.035095215,-0.020843506,-0.03857422,-0.02861023,-0.022155762,0.014709473,-0.028717041,0.0025691986,-0.009773254,0.004184723,-0.016326904,-0.026931763,0.024307251,0.014709473,-0.0053215027,0.010848999,-0.0026245117,0.018585205,0.0513916,0.0020923615,-0.027816772,0.026107788,0.013069153,0.0033302307,-0.001616478,0.044403076,0.031066895,-0.028900146,-0.0033111572,0.0009889603,-0.0066108704,-0.018051147,-0.018539429,0.01158905,0.032470703,-0.0038375854,-0.043121338,0.0209198,0.030578613,-0.033996582,-0.014343262,0.021759033,0.027938843,-0.037231445,0.02494812,0.022201538,0.054901123,-0.008514404,-0.007835388,-0.001625061,0.021240234,0.008094788,0.015182495,-0.009124756,0.016967773,-0.022232056,0.008842468,-0.0042915344,-0.01008606,0.021911621,-0.0053100586,-0.00021743774,0.022079468,0.0019388199,-0.006790161,-0.03491211,0.00009638071,-0.009407043,-0.01838684,0.011421204,0.013465881,0.027572632,-0.019577026,0.017318726,0.010108948,-0.025680542,-0.008468628,-0.010627747,0.04156494,-0.0023403168,0.0030879974,0.011024475,0.004711151,0.027557373,-0.055419922,-0.007320404,0.020492554,0.018539429,-0.027389526,-0.058502197,-0.027114868,-0.0134887695,0.048309326,0.005695343,0.008934021,0.022201538,-0.0058059692,-0.012588501,0.01651001,0.01084137,0.002407074,-0.020599365,-0.03515625,-0.019500732,0.0003540516,-0.008728027,-0.025985718,0.029541016,-0.019485474,-0.023757935,0.010803223,-0.011604309,-0.007949829,0.0069122314,0.010681152,0.0345459,-0.0033798218,0.01335144,-0.022521973,-0.04034424,0.0010557175,0.017120361,0.013191223,-0.04055786,0.015838623,-0.01600647,-0.018676758,-0.006378174,-0.002445221,0.016204834,0.027816772,-0.009757996,0.03475952,-0.0546875,0.042755127,-0.049713135,0.004047394,-0.0028858185,-0.029022217,-0.0013427734,-0.03060913,-0.019332886,0.034942627,-0.011779785,-0.00046515465,-0.019943237,-0.029159546,-0.0017852783,-0.06072998,0.026824951,0.025543213,0.03250122,-0.045440674,-0.0039749146,-0.0037212372,0.001964569,-0.0077209473,-0.007911682,-0.006504059,0.022872925,0.025421143,-0.011657715,-0.027114868,-0.02746582,-0.0064468384,-0.006160736,-0.037322998,-0.0546875,-0.004547119,0.029205322,0.004005432,0.0046081543,-0.025344849,-0.017745972,-0.0041885376,-0.042022705,0.012161255,-0.010025024,0.0029029846,-0.0021209717,-0.01626587,0.004299164,0.033233643,-0.037384033,0.042114258,-0.0025615692,-0.020645142,-0.033325195,0.0049591064,0.050872803,0.016098022,0.0037899017,-0.025268555,-0.011917114,-0.03286743,-0.044555664,-0.012924194,-0.010864258,-0.008758545,0.0074882507,0.0078048706,-0.04547119,-0.018539429,-0.030029297,-0.008140564,0.02229309,0.04269409,0.0016746521,0.0038452148,0.009590149,-0.010360718,-0.008575439,-0.03338623,0.011543274,0.010154724,-0.002603531,0.027389526,0.0385437,0.015914917,-0.014732361,0.000058948994,-0.010047913,0.01373291,-0.017654419,0.014625549,-0.028564453,0.0053367615,0.008773804,-0.017807007,-0.03265381,-0.00030064583,0.0736084,0.008224487,-0.0022773743,-0.0026626587,-0.01184082,0.028015137,0.036193848,-0.06774902,-0.008979797,-0.02822876,0.020507812,-0.014564514,0.025863647,0.005870819,-0.017929077,-0.011528015,-0.046203613,-0.004108429,0.010856628,0.003982544,-0.06982422,-0.009529114,-0.04434204,-0.01133728,-0.004722595,-0.014503479,0.002128601,0.0035076141,-0.025863647,-0.07702637,0.010864258,0.04901123,0.024780273,0.009849548,-0.01940918,-0.008758545,0.01348114,-0.039794922,-0.013519287,0.026184082,-0.019836426,-0.025680542,-0.027496338,0.03314209,-0.02671814,-0.019363403,0.016098022,-0.003868103,0.04397583,-0.0048065186,0.014266968,-0.01133728,0.0047950745,-0.013336182,0.0030841827,0.0002965927,-0.008766174,0.021530151,-0.048217773,0.02407837,0.021636963,0.021331787,0.0116119385,0.016952515,0.031204224,-0.052825928,-0.0027160645,0.023498535,-0.010070801,0.021697998,-0.030700684,0.045318604,0.021774292,-0.008407593,0.010421753,-0.020004272,-0.039489746,-0.048431396,-0.033721924,0.018325806,0.016342163,0.02331543,-0.018463135,-0.006401062,0.039154053,0.00078105927,0.00869751,-0.034820557,-0.018295288,-0.023849487,-0.0021343231,0.0036678314,0.0028514862,0.008094788,0.026870728,0.032165527,0.041931152,-0.009437561,-0.010643005,0.0031661987,0.017608643,-0.005844116,-0.006965637,0.014877319,0.0149002075,0.008712769,0.032165527,0.02243042,-0.03201294,-0.022369385,-0.027236938,-0.006881714,0.008392334,-0.0059051514,-0.01411438,-0.006717682,-0.00032234192,0.0044822693,-0.038757324,0.023422241,-0.043914795,-0.019882202,0.003376007,-0.01574707,0.023345947,0.017364502,0.009788513,-0.000172019,0.0071907043,0.061462402,0.020080566,-0.0002040863,0.027572632,0.053741455,0.0017995834,-0.015312195,-0.0063095093,-0.010299683,0.016937256,0.0012111664,-0.021011353,0.024505615,0.033477783,-0.014137268,0.010673523,0.0062179565,0.0259552,-0.022705078,0.0028057098,-0.0016450882,0.020004272,-0.024505615,0.04067993,-0.040527344,0.01020813,0.017913818,0.004058838,-0.00083732605,-0.031829834,-0.024154663,0.009170532,-0.000521183,-0.035247803,0.04058838,-0.012901306,0.014785767,-0.019500732,-0.026062012,0.012168884,-0.03677368,-0.014579773,0.027008057,-0.0116119385,-0.01210022,0.01626587,-0.018722534,0.028060913,-0.02746582,-0.004173279,0.014045715,-0.0054893494,-0.018814087,0.00031495094,-0.023986816,-0.004878998,-0.0077400208,-0.0116119385,-0.0033340454,0.049041748,0.045562744,0.021621704,0.03829956,0.0070152283,0.0095825195,-0.040618896,-0.019317627,0.014503479,-0.016738892,0.021224976,-0.01272583,0.053588867,0.031463623,0.012062073,0.033477783,0.033294678,0.01737976,-0.0040779114,0.011016846,0.0015983582,0.037109375,-0.003967285,0.02381897,-0.012245178,0.038116455,-0.046081543,0.0035629272,0.0032520294,0.022979736,-0.027008057,0.02835083,0.07873535,0.025314331,-0.022369385,0.050689697,-0.011253357,-0.0071029663,-0.020690918,-0.0067329407,0.04534912,0.00756073,0.035064697,0.029342651,0.014953613,0.0027980804,0.013084412,-0.02558899,-0.029464722,0.04928589,0.025283813,-0.021148682,-0.0071907043,-0.015838623,0.0066108704,-0.053253174,-0.022567749,0.011398315,-0.017105103,0.004425049,-0.019210815,0.008087158,-0.011703491,0.0005979538,0.011917114,0.017547607,-0.0154953,0.032470703,0.009597778,0.0062217712,0.029800415,0.0021572113,0.037994385,-0.030654907,-0.013122559,0.012611389,0.027236938,0.00020813942,-0.021102905,0.016738892,0.027191162,0.070495605,0.04034424,-0.01361084,0.0019721985,0.025482178,0.018951416,0.0057640076,0.04638672,0.027160645,0.0018815994,0.024093628,0.027374268,0.018920898,-0.028121948,-0.0020179749,-0.002527237,0.011497498,-0.020523071,-0.022003174,0.009094238,-0.018127441,0.020965576,0.000047385693,-0.015960693,0.034301758,0.035247803,0.0011520386,0.008552551,0.0057868958,0.011016846,0.0008006096,0.003168106,0.017105103,-0.008811951,0.018112183,0.011177063,0.01940918,-0.025726318,0.033203125,-0.010047913,-0.024978638,-0.024917603,-0.0020999908,-0.048614502,0.0047035217,-0.0005402565,-0.005722046,-0.031585693,0.01776123,0.029953003,0.009880066,0.0395813,0.022537231,-0.0015068054,-0.0010194778,0.00894165,0.016952515,-0.017028809,-0.013221741,-0.01626587,0.0060539246,0.029800415,-0.0017108917,0.018951416,-0.02809143,0.0061035156,0.010124207,-0.016845703,0.00749588,0.012832642,-0.018478394,-0.037353516,0.009933472,0.046569824,0.021484375,0.035247803,-0.004257202,-0.016601562,0.012077332,0.020721436,0.0067825317,0.0052719116,-0.020568848,0.021560669,-0.007881165,0.047973633,0.03149414,0.010101318,0.017913818,-0.017196655,-0.015342712,0.00078964233,-0.014450073,0.01890564,-0.02041626,0.013015747,0.00004053116,0.024627686,-0.029937744,-0.026641846,0.010871887,-0.010101318,-0.008781433,-0.021987915,0.005794525,0.018722534,0.023345947,0.041534424,0.022979736,-0.01525116,0.06604004,-0.0031375885,0.050994873,-0.022338867,-0.0075035095,0.04333496,0.030532837,0.027526855,0.011314392,-0.0047950745,-0.014320374,0.009811401,0.048736572,0.034729004,0.0019550323,0.0054473877,-0.017532349,0.023788452,0.009147644,0.029586792,-0.0031757355,-0.016326904,0.0068473816,-0.010101318,-0.029541016,0.009468079,-0.02017212,0.0056877136,0.042907715,-0.046417236,-0.021865845,-0.018188477,-0.031555176,0.019897461,-0.00067329407,0.010635376,-0.0036087036,-0.024612427,0.0048713684,-0.016784668,-0.012001038,-0.007965088,0.040130615,-0.050201416,-0.014175415,-0.0019130707,0.018814087,-0.019454956,0.031555176,0.04623413,-0.017456055,0.006126404,0.03930664,-0.008804321,0.04345703,-0.007904053,0.020965576,0.054748535,0.00856781,-0.006591797,0.015220642,-0.00038433075,-0.0234375,0.00957489,0.04071045,-0.0043411255,0.008628845,0.0067596436,-0.0044937134,-0.00040626526,0.010124207,-0.007801056,0.0019273758,-0.021652222,0.006881714,-0.009468079,0.021865845,0.0068359375,-0.007888794,-0.011558533,-0.010414124,0.01763916,0.02696228,0.005973816,-0.03555298,0.002626419,0.020843506,0.02456665,-0.01361084,-0.013374329,-0.014137268,-0.049865723,0.014808655,0.040008545,0.0154800415,0.001455307,-0.032196045,0.00003373623,0.018478394,0.013839722,0.010528564,-0.0007753372,-0.008590698,-0.001042366,-0.010803223,-0.01285553,-0.02229309,-0.010803223,0.012420654,0.034210205,-0.0013313293,-0.020324707,0.016723633,-0.0038547516,0.004447937,-0.0021476746,-0.0119018555,0.03643799,-0.0052223206,-0.014373779,-0.008522034,0.008628845,-0.03186035,-0.01335144,-0.016540527,0.015434265,0.039886475,-0.014656067,-0.021850586,0.00674057,0.009933472,0.019714355,0.027938843,0.0008044243,0.05340576,0.028121948,-0.0041046143,-0.02470398,0.017593384,-0.024291992,-0.022491455,0.009147644,-0.016601562,-0.027053833,0.030395508,0.0012369156,0.00008660555,-0.02998352,-0.013122559,0.0011520386,-0.017822266,0.025482178,-0.014205933,0.01008606,-0.036193848,-0.003660202,0.006122589,0.010498047,-0.030426025,-0.021896362,0.004547119,-0.0206604,-0.05618286,0.0059051514,-0.022369385,0.009819031,-0.02142334,0.002943039,0.006248474,0.032165527,-0.0032844543,0.005001068,0.011749268,0.030059814,0.00983429,0.010231018,0.03250122,-0.011810303,-0.021072388,-0.016098022,0.020126343,-0.020248413,0.028381348,-0.01373291,0.046295166,0.01335144,-0.0053749084,0.0029449463,-0.00415802,-0.015548706,-0.0035896301,-0.015548706,-0.016784668,0.027648926,0.024307251,-0.008384705,-0.010620117,0.047302246,-0.012680054,-0.01727295,0.027114868,0.04989624,-0.0026302338,0.03741455,0.004020691,-0.018554688,-0.020339966,-0.0019683838,-0.029647827,-0.0006504059,0.013298035,0.0073013306,-0.006427765,0.0018920898,0.0058059692,-0.018966675,0.013893127,0.016433716,0.010505676,-0.011146545,0.026443481,0.005168915,0.00774765,-0.028244019,-0.016433716,0.010757446,0.035583496,0.012931824,0.002149582,-0.0078125,0.012878418,-0.014785767,0.007106781,0.008850098,-0.01953125,-0.032043457,-0.023208618,-0.029174805,0.019241333,0.00982666,0.014526367,0.005592346,0.013069153,-0.0040283203,-0.033569336,-0.01309967,0.01928711,0.0057868958,-0.013031006,-0.012794495,0.0061073303,0.01071167,-0.025512695,0.01309967,-0.04171753,-0.03967285,-0.0045051575,-0.031555176,0.012916565,0.004383087,-0.015068054,0.008056641,-0.009025574,0.0023384094,0.015838623,0.016235352,-0.00073099136,-0.0064926147,0.006511688,0.009735107,-0.01398468,0.010856628,-0.012634277,-0.0057411194,0.019989014,-0.008255005,0.019058228,-0.007209778,0.02128601,-0.002029419,-0.0134887695,0.019760132,0.0008134842,0.010055542,-0.03744507,0.0024356842,-0.009796143,0.0032920837,0.019454956,-0.022003174,-0.01965332,0.006996155,-0.023483276,-0.028411865,-0.0015468597,0.031036377,0.03326416,-0.006252289,0.028747559,-0.020217896,0.0011110306,0.016143799,0.006336212,-0.010437012,-0.0028419495,0.040039062,0.0070495605,0.0002142191,-0.0044898987,0.010406494,-0.028411865,-0.015350342,0.0112838745,-0.0110321045,-0.009429932,0.01398468,0.0075683594,0.032806396,-0.0061035156,0.0045547485,0.027191162,-0.000064373016,0.022033691,-0.0016765594,0.040374756,-0.014732361,-0.024749756,0.0073127747,0.034362793,-0.021652222,0.008399963,-0.009399414,0.0005569458,-0.047698975,0.018341064,-0.006336212,0.023468018,-0.032196045,0.017715454,-0.011230469,-0.0068626404,-0.024993896,-0.0040664673,-0.041412354,0.0023288727,0.04232788,0.01651001,0.014770508,-0.007484436,-0.026184082,0.048553467,0.04714966,-0.0002837181,-0.024841309,-0.020446777,0.004421234,-0.0043792725,-0.0023422241,0.006591797,-0.030883789,-0.015838623,-0.00040316582,-0.0154418945,0.0064735413,0.00030732155,0.0035209656,0.012718201,-0.012504578,0.006198883,0.02809143,-0.006175995,-0.011116028,0.00056123734,-0.0013828278,0.050598145,0.029083252,-0.01637268,0.02607727,0.013557434,-0.028793335,0.05987549,-0.02456665,0.012413025,-0.01675415,-0.0011062622,-0.04147339,-0.02381897,-0.009567261,-0.0030517578],"createdAt":"2026-04-18T19:29:25.307Z","updatedAt":"2026-04-23T08:02:07.528Z","lastSeenAt":"2026-04-23T08:02:07.528Z","tsv":"'/api/v1/apikeys/27':90 '0.02':10,24,77,130 '000':119 '0x1a2b':135 '0x8335':124 '20':118 '2913':125 '300':141 '6':128 '85f3':136 'Base network API' 'USDC micropayment API' 'accept':109 'access':36,187 'address':134 'advertis':177 'ai':66 'analyt':65 'api':4,18,35,62,96,160,179 'api-key':95 'api-key-provisioning' 'appear':91 'base':8,22,85,120,127 'bodi':151,204 'call':79 'challeng':104 'confirm':105 'connect':168 'content':174 'crawl':156 'crypto-paid API' 'data':64 'decim':129 'detail':146 'difficult':199 'doc':158 'document':147,196,221 'endpoint':6,20,30,47,101,191,207 'exact':115 'exampl':149 'expect':208 'experiment':222 'financ':69 'found':153 'gate':3,17 'host':54 'howev':192 'infrastructur':72 'instant':186 'key':5,19,97,180 'know':201 'lack':194 'learn':68 'light':220 'lightly-docu':219 'limit':184 'live':108 'lowpaymentfee' 'lowpaymentfee.com':32,51 'machin':67 'make':197 'manag':100 'mani':46 'network':86 'offer':48 'one':44 'openapi':144 'page':163 'particular':206 'pay':9,23,59 'pay-per-call API' 'pay-per-request':58 'payment':40,116,138 'payto':133 'per':13,27,60,78 'platform':52,176 'post':110 'post-endpoint' 'premium':34 'premium API access' 'price':75,159 'prompt':170 'protocol':41 'provid':33 'provis':98 'rate':183 'readm':162 'request':14,28,61,111,203 'request/response':150 'requir':113,181 'resourc':89 'return':165,212 'schema':145 'second':142 'servic':223 'settl':80 'span':63 'specif':88 'substant':173 'timeout':139 'treat':215 'unit':121 'usdc':12,26,82,123 'usdc-base' 'user':213 'util':73 'varieti':56 'via':37 'wallet':169 'web3':70 'x402':2,16,39,103 'x402 API key' 'x402-gated':1,15 'x402-payment'","prices":[{"id":"b1338d0e-519f-4bfa-9182-7c95fb6bc5df","listingId":"9136e310-81ab-422b-8d77-c8f52c834d4b","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/apikeys/27","description":"Premium API Access","outputSchema":{"input":{"type":"http","method":"GET","discoverable":true}},"maxAmountRequired":"20000","maxTimeoutSeconds":300}],"asset_contract":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","max_timeout_seconds":300},"createdAt":"2026-04-18T19:29:25.307Z"}],"sources":[{"listingId":"9136e310-81ab-422b-8d77-c8f52c834d4b","source":"x402_bazaar","sourceId":"https://lowpaymentfee.com/api/v1/apikeys/27","sourceUrl":"https://api.cdp.coinbase.com/platform/v2/x402/discovery/resources","isPrimary":true,"firstSeenAt":"2026-04-18T19:29:25.307Z","lastSeenAt":"2026-04-23T08:02:07.528Z"}],"details":{"listingId":"9136e310-81ab-422b-8d77-c8f52c834d4b","quickStartSnippet":"curl -X POST https://lowpaymentfee.com/api/v1/apikeys/27 \\\n  -H \"X-PAYMENT: <x402-payment-header>\" \\\n  -H \"Content-Type: application/json\"","exampleRequest":null,"exampleResponse":null,"schema":{"input":{"type":"http","method":"GET","discoverable":true}},"openapiUrl":null,"agentsTxtUrl":null,"citations":[{"claim":"The endpoint returns a valid x402 challenge with maxAmountRequired of 20000 base units of USDC on Base","source_url":"https://lowpaymentfee.com/api/v1/apikeys/27"},{"claim":"All endpoints on the platform are priced at $0.02 per request with no API keys, no rate limits, and instant access","source_url":"https://lowpaymentfee.com"},{"claim":"The USDC asset address is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base network","source_url":"https://lowpaymentfee.com/api/v1/apikeys/27"}],"useCases":["Programmatically provisioning or retrieving API keys via a single micropayment","Agents purchasing API access on-the-fly without pre-registration","Demonstrating x402 payment-gated endpoint integration"],"bestFor":["Developers experimenting with x402 payment protocol","AI agents that need to acquire API keys autonomously","Users who want no-signup, pay-per-use API access on Base"],"notFor":["Production workloads requiring detailed API documentation and SLAs","Users who cannot transact in USDC on the Base network","High-volume use cases where per-request pricing may be inefficient"],"kindDetails":{"x402_version":1,"resource_type":"http","bazaar_last_updated":"2026-02-17T23:13:29.432Z"},"updatedAt":"2026-04-23T08:02:07.528Z"}}