{"id":"da9d1ede-b08b-403a-9aae-0a9f9e5c2696","shortId":"xP4FMa","kind":"x402","title":"x402-gated premium API endpoint on Base, payable in USDC per request.","tagline":"x402-gated premium API endpoint on Base, payable in USDC per request.","description":"This endpoint at `/api/endpoint-50` is part of the lowpaymentfee.com platform, which hosts a collection of x402 protocol-gated APIs spanning data & analytics, AI/ML inference, finance/Web3, and infrastructure utilities. The specific functionality of `/api/endpoint-50` is not documented — the site's landing page lists endpoints under `/api/v1/` and `/api/v2/` paths, but `/api/endpoint-50` does not appear among them. It is described only as \"Premium API Access\" in the x402 challenge.\n\nThe endpoint is live and returns a valid x402 payment challenge. It accepts POST requests and requires payment of up to 20,000 units of USDC (contract `0x8335…2913`) on the Base network via the `exact` payment scheme. The platform advertises $0.02 per request across its listed endpoints, no API keys, no rate limits, and instant access. However, the relationship between the 20,000 raw token units in the challenge and the advertised $0.02 price is unclear without knowing the decimal handling.\n\nBecause the endpoint path does not match any documented API on the site and no input/output schema, example payloads, or functional description are available, the actual capability behind this endpoint remains unknown. The docs, pricing, API, and README pages all returned only a \"Connect wallet\" prompt with no substantive content.","tags":[],"capabilities":["x402-payment","usdc-payment","base-network","post-endpoint","pay-per-request"],"categories":["api","payments"],"synonyms":["premium API","x402 endpoint","USDC API","Base network API","pay-per-call API","lowpaymentfee","micropayment API"],"warnings":["The path /api/endpoint-50 does not appear in the site's documented API catalog — its actual functionality is unknown.","All documentation pages (docs, pricing, API, README) returned only a 'Connect wallet' prompt with no content.","No input or output schema is available; callers cannot know what to send or what to expect back.","The relationship between the 20,000 maxAmountRequired in the challenge and the advertised $0.02/request price is unclear."],"endpointUrl":"https://lowpaymentfee.com/api/endpoint-50","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/endpoint-50","description":"Premium API Access","outputSchema":{"input":{"type":"http","method":"GET","discoverable":true}},"maxAmountRequired":"20000","maxTimeoutSeconds":300}]},"qualityScore":"0.250","qualityRationale":"The endpoint is live and returns a valid 402 challenge, but the actual functionality behind /api/endpoint-50 is completely undocumented. No input schema, output schema, examples, or description beyond 'Premium API Access' exist. The docs pages are empty. This is effectively a stub listing.","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":"2026-04-18T19:35:32.776Z","embedding":[-0.019012451,-0.029312134,0.040771484,0.020324707,0.0023345947,-0.025497437,-0.014709473,0.037353516,0.06970215,-0.06451416,0.045532227,-0.050109863,-0.042877197,-0.04989624,-0.02319336,0.010017395,-0.0154953,0.0040893555,-0.046722412,0.038909912,0.0446167,-0.019744873,-0.011222839,0.046783447,0.0007991791,-0.02178955,-0.008552551,0.002981186,-0.0069351196,-0.020141602,0.025970459,-0.025909424,0.0012617111,0.00970459,-0.021896362,0.0026664734,0.00655365,0.056488037,0.030456543,-0.004737854,0.0041236877,-0.06542969,-0.01612854,0.0007414818,-0.04321289,-0.0006480217,0.014678955,-0.0317688,-0.014442444,0.011390686,-0.021881104,-0.0022773743,-0.015449524,0.0025577545,0.0059013367,0.010643005,-0.014694214,-0.016601562,0.0038032532,0.016677856,-0.0087890625,-0.068847656,-0.0056533813,0.0064468384,0.019317627,0.038513184,-0.0129852295,0.049804688,0.003484726,0.06585693,0.03793335,0.05911255,0.027618408,0.019958496,-0.008850098,-0.0015993118,0.00006240606,0.041015625,-0.011383057,-0.026275635,-0.019088745,-0.010482788,-0.05734253,-0.015586853,-0.01600647,-0.050323486,-0.02381897,0.015548706,-0.025894165,0.021987915,-0.076293945,-0.0037670135,-0.012313843,0.018463135,-0.018630981,-0.0073547363,-0.026412964,0.010398865,-0.007221222,0.016845703,0.010513306,-0.04156494,0.02734375,0.01309967,0.051361084,0.03213501,0.01763916,0.036224365,0.0065994263,-0.028335571,-0.009246826,0.012489319,-0.0032215118,-0.0035800934,0.030899048,0.0017089844,-0.013023376,0.010902405,-0.012741089,0.032562256,-0.0491333,0.055908203,0.0052375793,-0.038391113,0.0053482056,-0.038116455,0.0028686523,-0.004634857,-0.039886475,0.0026988983,0.022613525,0.0134887695,0.011878967,-0.014549255,-0.029418945,0.00762558,-0.034484863,-0.011550903,-0.053375244,-0.0231781,0.022460938,-0.027954102,0.027114868,0.030960083,-0.09399414,-0.0013008118,-0.051452637,0.023208618,-0.041778564,-0.015701294,0.011306763,0.014137268,-0.013763428,-0.018661499,-0.009666443,-0.014831543,-0.011650085,0.044891357,-0.0029945374,0.036468506,0.006591797,0.016235352,0.020889282,0.018829346,0.032440186,0.05496216,0.008666992,-0.064575195,-0.08770752,-0.04626465,-0.00299263,-0.011642456,-0.04638672,-0.0046310425,0.0006842613,-0.06817627,-0.039733887,-0.018600464,0.0000833869,-0.04421997,0.005847931,-0.030715942,0.012275696,0.0047836304,-0.065979004,-0.03074646,-0.031799316,0.06100464,0.024658203,0.0038661957,0.03451538,-0.0036773682,0.063964844,0.004173279,-0.021957397,-0.040649414,0.025405884,-0.017471313,0.048217773,0.011375427,0.005088806,-0.026428223,0.03540039,0.07556152,0.02128601,-0.007194519,0.0018997192,-0.0309906,-0.03262329,-0.041625977,0.0055122375,0.014060974,0.0036373138,0.028701782,-0.028564453,-0.040771484,-0.011627197,0.005332947,0.0206604,0.06048584,0.009689331,0.009979248,0.015808105,0.017593384,-0.037963867,0.04537964,0.01411438,0.028640747,-0.019454956,-0.0211792,0.013885498,0.02645874,-0.027740479,-0.013542175,-0.023025513,0.032226562,-0.0028381348,0.004676819,0.029159546,-0.017868042,-0.029815674,-0.026275635,-0.010765076,0.01525116,0.0017309189,-0.02949524,-0.044647217,-0.059936523,0.046661377,0.06506348,0.039154053,0.007972717,0.012283325,-0.014656067,-0.013702393,-0.060150146,0.043273926,0.06536865,-0.025466919,-0.018096924,0.012588501,-0.01763916,-0.046447754,-0.022247314,0.0014076233,-0.017715454,-0.025283813,0.008399963,-0.029388428,-0.00085783005,0.0151901245,0.024627686,0.036468506,-0.014511108,-0.049621582,-0.037872314,-0.000013232231,0.031982422,-0.031707764,-0.017410278,0.0015478134,0.00868988,0.02809143,-0.0030212402,0.020492554,-0.009895325,0.014625549,0.0021800995,0.0065231323,-0.02142334,-0.03100586,0.025482178,-0.008338928,-0.074401855,0.0121536255,0.0071372986,0.05596924,-0.049041748,0.045410156,-0.018753052,0.0023403168,0.068481445,-0.028305054,-0.06616211,-0.00096178055,0.0047073364,0.050842285,0.04840088,0.0032081604,-0.01197052,0.004558563,0.050720215,-0.009124756,0.0021095276,0.022644043,0.033721924,0.029312134,0.015731812,-0.051452637,-0.02507019,-0.0077400208,-0.009475708,0.024841309,-0.0099105835,0.039093018,-0.010437012,0.00094509125,-0.024307251,0.005218506,-0.030075073,-0.0048713684,-0.019363403,-0.00756073,-0.021759033,-0.0053901672,0.019348145,0.014442444,-0.007633209,0.008583069,0.04055786,0.021896362,-0.00907135,-0.011108398,-0.022628784,-0.022201538,0.01626587,0.019012451,0.01574707,0.012283325,0.024276733,-0.053619385,0.0073280334,0.02017212,0.009239197,0.036346436,-0.021759033,0.01751709,-0.05847168,-0.071899414,-0.015655518,-0.03918457,0.03677368,0.009971619,0.0105896,0.04232788,0.0048675537,-0.013710022,-0.03640747,0.02772522,-0.04510498,-0.004272461,0.038757324,-0.013595581,-0.03111267,0.0035972595,0.010543823,0.014297485,0.025512695,0.014762878,0.0058059692,0.064331055,0.03805542,0.011871338,0.021697998,0.00843811,0.035186768,-0.0059165955,-0.0184021,-0.030349731,-0.018081665,0.023422241,-0.018630981,-0.014389038,-0.08325195,0.05053711,0.028137207,0.07904053,0.016845703,0.015670776,0.042907715,-0.012260437,0.005859375,-0.032592773,-0.032348633,-0.027618408,-0.0385437,0.024032593,-0.012550354,-0.01436615,-0.01461792,0.019958496,0.009521484,0.01991272,-0.041992188,0.070007324,0.011306763,-0.00018894672,0.011138916,0.0078048706,0.045837402,0.048980713,-0.04397583,0.017562866,0.023101807,-0.031585693,0.004070282,0.04837036,-0.009597778,-0.005493164,-0.06085205,-0.030136108,0.004085541,-0.0043029785,-0.05532837,-0.0065193176,0.008460999,0.032989502,0.027740479,-0.02420044,-0.04144287,0.0035247803,-0.012283325,-0.045043945,-0.020462036,-0.039123535,0.030639648,0.047180176,-0.022766113,-0.0048294067,0.0068244934,-0.009902954,-0.003993988,0.020080566,-0.0118637085,0.0006594658,-0.045318604,0.03237915,0.0063972473,0.027404785,0.033843994,0.026000977,0.03213501,0.030288696,0.04147339,0.0050811768,-0.0067100525,-0.048065186,0.014816284,-0.053741455,0.0069770813,0.0132369995,-0.01763916,0.004837036,-0.018127441,-0.031951904,-0.026245117,0.014625549,-0.016326904,0.00806427,0.02494812,-0.045288086,-0.046691895,-0.05050659,-0.026321411,0.0049705505,0.075805664,0.02607727,-0.009552002,-0.06286621,-0.0124053955,0.04272461,-0.0010080338,0.0025081635,-0.0154418945,-0.011550903,-0.01751709,-0.029052734,-0.020324707,-0.022979736,0.032165527,-0.0055351257,-0.00995636,0.028335571,-0.004058838,0.025405884,-0.016738892,0.004558563,0.04257202,-0.024978638,-0.0019817352,-0.04626465,0.029876709,0.0013751984,-0.012001038,-0.064331055,0.051574707,0.006008148,0.04156494,-0.032806396,0.009597778,0.008834839,0.027740479,0.0051879883,-0.018096924,-0.019302368,0.009292603,-0.04748535,-0.08703613,0.029174805,-0.018478394,0.029632568,0.011871338,0.0134887695,0.03704834,-0.016540527,0.00011140108,0.025436401,-0.017242432,-0.009407043,-0.03768921,-0.036987305,-0.01991272,0.011779785,-0.010185242,0.014831543,0.0017490387,0.0067253113,0.000051379204,-0.02609253,0.03100586,0.0058670044,0.0044021606,0.023925781,-0.008705139,0.013755798,0.03640747,-0.0006008148,-0.039245605,0.022720337,0.0063591003,-0.0068244934,-0.0025978088,0.04928589,0.022644043,-0.0155181885,-0.0003759861,-0.0023880005,-0.011100769,-0.03265381,-0.015625,0.0009937286,0.04159546,0.0029792786,-0.034179688,0.032928467,0.012306213,-0.036193848,-0.011878967,0.020980835,0.026809692,-0.032409668,0.019500732,0.025619507,0.049438477,-0.028442383,-0.0076408386,0.0014410019,0.0234375,0.021606445,0.018127441,-0.018844604,0.016464233,-0.0079956055,0.026046753,-0.005092621,-0.020019531,0.009986877,-0.012962341,0.028274536,0.017608643,0.024017334,-0.027420044,-0.017303467,-0.007873535,-0.010147095,-0.017623901,0.021270752,0.024627686,0.018218994,-0.02217102,0.03274536,0.014457703,-0.03503418,-0.017822266,-0.007621765,0.033416748,-0.010131836,0.0014190674,0.010879517,0.013656616,0.027923584,-0.055664062,0.0033054352,0.0005507469,0.019134521,-0.023971558,-0.049438477,-0.03277588,0.007904053,0.032562256,0.022644043,0.0047683716,0.030685425,-0.016540527,0.0028858185,0.009933472,-0.0026454926,-0.010520935,-0.019363403,-0.049072266,-0.007007599,-0.0027065277,-0.008964539,-0.022964478,0.0038757324,-0.014587402,-0.019042969,0.0065460205,-0.009674072,-0.00044751167,-0.0033016205,0.014724731,0.029571533,-0.013336182,0.008277893,-0.020736694,-0.03060913,0.0031375885,0.01940918,0.027877808,-0.030670166,0.014083862,-0.018066406,-0.0017137527,-0.008964539,0.020935059,0.02418518,0.018203735,0.0036449432,0.018737793,-0.049102783,0.037902832,-0.02748108,0.01675415,0.011070251,-0.034240723,-0.004688263,-0.026000977,-0.013534546,0.03414917,-0.01625061,-0.00737381,-0.03010559,-0.03387451,-0.016143799,-0.049621582,0.013031006,0.023620605,0.036010742,-0.039123535,0.004558563,0.0021247864,-0.005809784,-0.0057792664,0.001452446,-0.005832672,0.025878906,0.028060913,0.011993408,-0.024780273,-0.02519226,-0.00053071976,-0.018844604,-0.045654297,-0.050964355,-0.029663086,0.0135650635,0.00031638145,-0.0017223358,-0.025375366,-0.024017334,-0.0036182404,-0.048919678,0.0027008057,0.008392334,0.020004272,0.022827148,-0.02027893,-0.004623413,0.017181396,-0.023803711,0.029342651,-0.0051193237,0.0014152527,-0.039520264,-0.008491516,0.04336548,0.030075073,0.006916046,-0.01651001,0.0053520203,-0.03665161,-0.058898926,0.0024318695,-0.014320374,0.0050086975,0.0054969788,-0.007911682,-0.05783081,-0.009262085,-0.023620605,0.009712219,0.017929077,-0.00024676323,0.02645874,0.009307861,0.0077590942,-0.01084137,-0.024108887,-0.042053223,0.0016555786,0.011070251,0.004623413,0.017669678,0.05102539,0.009521484,0.0048980713,0.014533997,-0.004917145,0.016815186,-0.031707764,0.010353088,-0.0018501282,0.006843567,-0.0061416626,-0.0127334595,-0.03488159,0.013587952,0.08087158,-0.012794495,0.01374054,-0.0067214966,-0.017944336,0.019104004,0.023834229,-0.053253174,0.0012969971,-0.028671265,0.013282776,-0.012435913,0.023269653,0.012016296,0.022705078,-0.027160645,-0.051574707,-0.0042495728,0.01864624,0.0004580021,-0.059417725,-0.016906738,-0.058685303,-0.011756897,-0.018234253,-0.016281128,0.007751465,0.0012807846,-0.017669678,-0.08984375,0.006626129,0.049621582,0.0074920654,0.0087890625,-0.01864624,0.015266418,0.016601562,-0.02267456,-0.029449463,0.03543091,-0.024627686,0.0014400482,-0.0317688,0.04525757,-0.0236969,-0.024765015,0.027908325,0.0061531067,0.00756073,-0.017486572,0.015991211,-0.013336182,0.011245728,-0.005290985,0.015281677,-0.008453369,-0.02420044,0.022506714,-0.045654297,0.024932861,0.016494751,0.0005187988,-0.0032291412,0.034423828,0.026168823,-0.045013428,-0.010299683,0.036376953,0.004890442,0.039733887,-0.03515625,0.03543091,0.012466431,-0.010803223,0.0025844574,-0.013336182,-0.020996094,-0.036468506,-0.04550171,0.0129852295,0.005302429,0.012237549,-0.014152527,0.011795044,0.022018433,0.012481689,0.007041931,-0.010047913,-0.012680054,-0.01335144,0.009010315,-0.0011844635,-0.000104904175,-0.0007390976,0.02217102,0.024505615,0.04940796,-0.0058174133,-0.013114929,0.013763428,0.022903442,-0.015602112,0.008888245,0.017929077,0.006942749,0.010040283,0.018493652,0.027633667,-0.028945923,-0.016235352,0.00036931038,-0.0047302246,0.0073890686,-0.005908966,-0.0047683716,0.0025463104,-0.005054474,-0.0019702911,-0.044769287,0.018081665,-0.032836914,-0.036834717,0.0008096695,-0.016906738,0.0060653687,0.020324707,-0.0018033981,0.006465912,-0.008781433,0.03540039,0.0017757416,-0.022720337,0.026672363,0.038085938,0.0017089844,-0.024963379,0.004447937,-0.0005760193,-0.007835388,0.010749817,-0.012329102,0.001865387,0.046051025,-0.018432617,0.021575928,-0.0041236877,0.015052795,-0.0016050339,0.017623901,-0.0039901733,0.013252258,-0.016326904,0.032043457,-0.05532837,0.008995056,0.019897461,0.006958008,-0.015197754,-0.035858154,-0.030136108,0.021148682,0.01134491,-0.016738892,0.045043945,-0.005130768,0.030059814,-0.023544312,-0.022323608,0.000074744225,-0.0236969,-0.014122009,0.026290894,-0.009300232,0.017623901,0.026245117,-0.025390625,0.025360107,-0.041229248,0.015304565,0.009162903,0.01574707,-0.019378662,-0.025375366,-0.013519287,-0.016616821,-0.009864807,-0.001244545,-0.00157547,0.054840088,0.025650024,0.015266418,0.024383545,0.011474609,0.009613037,-0.0491333,-0.02659607,0.009536743,-0.028549194,0.0211792,-0.01965332,0.049560547,0.047210693,-0.009933472,0.039215088,0.047424316,0.029525757,0.0055122375,0.016647339,-0.0058937073,0.016952515,-0.01499939,0.013069153,0.010093689,0.048309326,-0.030319214,0.011749268,0.0073623657,0.021591187,-0.031829834,0.037139893,0.067993164,0.031585693,-0.010391235,0.04458618,-0.0116119385,-0.024993896,-0.018875122,-0.010803223,0.042388916,0.0098724365,0.048706055,0.025283813,0.009986877,-0.024047852,0.017471313,-0.017211914,-0.041168213,0.050750732,0.03338623,-0.012588501,0.0017061234,-0.0023117065,0.0038166046,-0.04852295,-0.030563354,0.017044067,-0.0029678345,0.007671356,-0.00031971931,0.002117157,-0.011741638,0.027923584,0.009994507,0.011390686,-0.021316528,0.021896362,0.025115967,0.007865906,0.021057129,0.0059776306,0.021957397,-0.023147583,-0.0062446594,0.010139465,0.019897461,-0.003364563,-0.0010004044,0.025604248,0.022415161,0.048339844,0.042266846,-0.0137786865,-0.0066490173,0.033447266,0.01637268,-0.0063667297,0.042938232,0.016723633,0.0072364807,0.0362854,0.027130127,0.012687683,-0.027404785,0.019012451,-0.0090789795,0.019958496,-0.008125305,-0.022354126,0.011886597,-0.005630493,0.008575439,0.0024089813,-0.014389038,0.02406311,0.023269653,-0.0064468384,0.0013847351,0.0019550323,0.004333496,-0.012252808,-0.001376152,0.005279541,-0.01777649,0.02734375,0.013473511,0.03604126,-0.0317688,0.03466797,0.0010757446,-0.0077056885,0.0054855347,0.017623901,-0.039215088,-0.0007429123,0.0079193115,-0.012199402,-0.037872314,0.011199951,0.02053833,-0.008110046,0.030639648,0.0034980774,0.009605408,0.013191223,0.03074646,0.0178833,-0.011604309,-0.011665344,-0.020874023,0.032409668,0.033935547,-0.0018949509,-0.00024819374,-0.03050232,0.0040512085,0.020370483,-0.0049057007,-0.007221222,-0.0043144226,-0.014419556,-0.051696777,0.007713318,0.047302246,0.019989014,0.03149414,-0.0025939941,-0.017669678,-0.00017082691,0.028961182,-0.0012178421,-0.025741577,-0.03010559,0.022720337,-0.01210022,0.0513916,0.036865234,-0.0026454926,0.034606934,-0.011001587,-0.026657104,-0.0025405884,-0.01512146,0.021087646,-0.013710022,0.0017585754,-0.022781372,0.021209717,-0.022109985,-0.0362854,0.0049552917,-0.020248413,-0.016677856,-0.024551392,0.011749268,0.015396118,0.019012451,0.044189453,0.011413574,-0.019958496,0.06921387,-0.012535095,0.044128418,-0.018539429,0.0004556179,0.050842285,0.03100586,0.039154053,0.02255249,0.01902771,-0.026245117,0.016662598,0.03277588,0.033813477,0.016601562,-0.0041999817,-0.010238647,0.033203125,-0.0022583008,0.018844604,-0.0070762634,-0.009063721,0.016799927,-0.0063095093,-0.0066452026,0.0057640076,-0.009666443,0.017745972,0.034942627,-0.027191162,-0.0072402954,-0.014015198,-0.011421204,0.04534912,0.008087158,0.0023498535,0.0035171509,-0.015083313,0.01701355,-0.02758789,-0.019104004,0.0061798096,0.026809692,-0.05050659,-0.017211914,0.011520386,0.022109985,-0.020187378,0.029281616,0.026870728,-0.0072135925,0.014625549,0.047424316,-0.0010576248,0.05065918,-0.012367249,0.022705078,0.035064697,-0.0017671585,-0.017913818,0.019638062,0.018157959,-0.0236969,0.01638794,0.036346436,0.00046682358,0.0055007935,-0.00097322464,-0.01979065,0.010368347,0.009521484,-0.019424438,-0.008087158,-0.02319336,-0.02406311,0.011184692,0.015357971,0.001666069,0.0051116943,-0.00053977966,-0.014015198,0.0022335052,0.04196167,0.011306763,-0.04373169,0.011741638,0.0023975372,0.018569946,-0.03479004,-0.0158844,-0.0154800415,-0.027313232,0.01033783,0.02281189,0.0026226044,0.010864258,-0.01828003,-0.007633209,0.03048706,0.017303467,0.028167725,0.0064048767,0.0062217712,0.024719238,-0.0115356445,0.0049552917,-0.008300781,0.0052871704,0.009567261,0.006187439,-0.008033752,-0.025497437,0.019866943,-0.008674622,0.015655518,0.002620697,-0.012039185,0.037902832,-0.022720337,-0.0042800903,0.0012102127,0.013061523,-0.012138367,-0.018661499,-0.02357483,0.02722168,0.04788208,-0.016281128,-0.01033783,0.013618469,0.02734375,0.026031494,0.024154663,0.001865387,0.04373169,0.019241333,-0.014678955,-0.032470703,0.016159058,-0.007419586,-0.024871826,0.023498535,-0.01878357,-0.0072135925,0.022384644,0.013504028,0.0012731552,-0.036254883,-0.02116394,-0.014259338,-0.027923584,0.024353027,-0.014694214,0.007873535,-0.029663086,-0.018096924,0.012084961,-0.01386261,-0.023162842,-0.032440186,0.00046348572,-0.024673462,-0.042785645,0.012229919,-0.02078247,0.009353638,-0.023101807,-0.0064582825,-0.015090942,0.04006958,-0.008544922,0.0045051575,0.0054779053,0.023468018,0.0037899017,0.011474609,0.021896362,-0.021392822,-0.028701782,-0.012130737,-0.015655518,-0.023010254,0.017669678,-0.019805908,0.032287598,0.010169983,-0.00137043,0.0034751892,-0.011726379,-0.010673523,0.0016222,-0.03829956,-0.017150879,0.010055542,0.028060913,-0.003753662,-0.015388489,0.0395813,-0.017868042,-0.011665344,0.022216797,0.03475952,0.010696411,0.03286743,-0.0054016113,-0.0112838745,-0.024337769,0.00018239021,-0.01675415,0.005207062,0.007507324,0.0032520294,-0.0158844,0.005138397,0.018859863,-0.012176514,0.004173279,0.027557373,-0.006790161,-0.013977051,0.037261963,0.009155273,0.007419586,-0.009750366,-0.016433716,0.02758789,0.042266846,0.008331299,-0.000078082085,-0.003124237,0.015571594,-0.008964539,0.0005950928,0.022720337,-0.019561768,-0.03250122,-0.004875183,-0.02999878,0.025741577,-0.004798889,0.010749817,-0.0015134811,0.013511658,-0.01751709,-0.03656006,-0.01309967,0.0129852295,0.011619568,-0.00894928,0.0023899078,-0.0045661926,0.01361084,-0.034332275,0.009902954,-0.04360962,-0.027740479,-0.020187378,-0.025177002,0.01436615,0.002002716,-0.004432678,0.0015172958,-0.0035209656,-0.013710022,0.009651184,0.029922485,-0.01625061,-0.013298035,0.02293396,0.024780273,-0.020217896,0.019882202,-0.029312134,-0.008880615,0.012268066,-0.0026874542,0.014579773,-0.009735107,0.021469116,0.0050811768,-0.017669678,0.01914978,0.0026054382,0.02456665,-0.022644043,0.0004916191,-0.0063552856,0.007724762,0.011497498,-0.016159058,-0.021255493,-0.0022621155,-0.016296387,-0.042297363,0.008728027,0.025466919,0.032165527,-0.016799927,0.031402588,-0.012023926,-0.026245117,0.014030457,0.009010315,-0.021316528,0.0088272095,0.036376953,-0.0009908676,-0.0040283203,0.003993988,-0.011802673,-0.025848389,-0.00869751,0.0152282715,-0.016998291,0.0003311634,0.024353027,0.006298065,0.036315918,0.004371643,0.018875122,0.017120361,0.008682251,0.039733887,0.009170532,0.05078125,0.008522034,-0.02456665,0.00522995,0.017807007,-0.023498535,-0.0051345825,-0.010025024,0.006591797,-0.037078857,0.01512146,-0.00434494,0.025894165,-0.00868988,0.024307251,-0.02293396,0.005870819,-0.032165527,0.00080919266,-0.028747559,0.010292053,0.030075073,0.010292053,0.009010315,-0.004184723,-0.035614014,0.019210815,0.041168213,-0.006931305,-0.042999268,-0.0041656494,0.019042969,0.011512756,0.0038166046,0.014221191,-0.030349731,-0.020889282,-0.01171875,-0.00459671,-0.004924774,-0.00055885315,0.024337769,0.014221191,-0.0028591156,-0.0002439022,0.026763916,0.0014028549,0.01474762,0.01512146,0.0011510849,0.026672363,0.030288696,-0.020980835,0.02218628,0.024215698,-0.030853271,0.04547119,-0.01146698,0.019378662,-0.0211792,0.0020637512,-0.042816162,-0.008178711,-0.02078247,0.012832642],"createdAt":"2026-04-18T18:31:53.039Z","updatedAt":"2026-04-23T05:00:37.084Z","lastSeenAt":"2026-04-23T05:00:37.084Z","tsv":"'/api/endpoint-50':30,60,77 '/api/v1':72 '/api/v2':74 '0.02':136,168 '000':117,158 '0x8335':122 '20':116,157 '2913':123 'Base network API' 'USDC API' 'accept':107 'access':90,151 'across':139 'actual':202 'advertis':135,167 'ai/ml':50 'among':81 'analyt':49 'api':5,18,46,89,144,186,212 'appear':80 'avail':200 'base':8,21,126 'base-network' 'behind':204 'capabl':203 'challeng':94,105,164 'collect':40 'connect':220 'content':226 'contract':121 'data':48 'decim':175 'describ':85 'descript':198 'doc':210 'document':63,185 'endpoint':6,19,28,70,96,142,179,206 'exact':130 'exampl':194 'finance/web3':52 'function':58,197 'gate':3,16,45 'handl':176 'host':38 'howev':152 'infer':51 'infrastructur':54 'input/output':192 'instant':150 'key':145 'know':173 'land':67 'limit':148 'list':69,141 'live':98 'lowpaymentfee' 'lowpaymentfee.com':35 'match':183 'micropayment API' 'network':127 'page':68,215 'part':32 'path':75,180 'pay-per-call API' 'pay-per-request' 'payabl':9,22 'payload':195 'payment':104,112,131 'per':12,25,137 'platform':36,134 'post':108 'post-endpoint' 'premium':4,17,88 'premium API' 'price':169,211 'prompt':222 'protocol':44 'protocol-g':43 'rate':147 'raw':159 'readm':214 'relationship':154 'remain':207 'request':13,26,109,138 'requir':111 'return':100,217 'schema':193 'scheme':132 'site':65,189 'span':47 'specif':57 'substant':225 'token':160 'unclear':171 'unit':118,161 'unknown':208 'usdc':11,24,120 'usdc-payment' 'util':55 'valid':102 'via':128 'wallet':221 'without':172 'x402':2,15,42,93,103 'x402 endpoint' 'x402-gated':1,14 'x402-payment'","prices":[{"id":"3b5176aa-8602-4263-a51e-d95971062499","listingId":"da9d1ede-b08b-403a-9aae-0a9f9e5c2696","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/endpoint-50","description":"Premium API Access","outputSchema":{"input":{"type":"http","method":"GET","discoverable":true}},"maxAmountRequired":"20000","maxTimeoutSeconds":300}],"asset_contract":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","max_timeout_seconds":300},"createdAt":"2026-04-18T18:31:53.039Z"}],"sources":[{"listingId":"da9d1ede-b08b-403a-9aae-0a9f9e5c2696","source":"x402_bazaar","sourceId":"https://lowpaymentfee.com/api/endpoint-50","sourceUrl":"https://api.cdp.coinbase.com/platform/v2/x402/discovery/resources","isPrimary":true,"firstSeenAt":"2026-04-18T18:31:53.039Z","lastSeenAt":"2026-04-23T05:00:37.084Z"}],"details":{"listingId":"da9d1ede-b08b-403a-9aae-0a9f9e5c2696","quickStartSnippet":"curl -X POST https://lowpaymentfee.com/api/endpoint-50\n# Returns 402 with X-PAYMENT challenge; attach a valid x402 payment header to proceed.","exampleRequest":null,"exampleResponse":null,"schema":{"input":{"type":"http","method":"GET","discoverable":true}},"openapiUrl":null,"agentsTxtUrl":null,"citations":[{"claim":"The site lists APIs across data/analytics, AI/ML, finance/Web3, and infrastructure categories at $0.02/request","source_url":"https://lowpaymentfee.com"},{"claim":"The platform advertises no API keys, no rate limits, instant access, and Base network payments","source_url":"https://lowpaymentfee.com"},{"claim":"The endpoint returns a 402 challenge requiring USDC payment on Base with maxAmountRequired of 20000","source_url":"https://lowpaymentfee.com/api/endpoint-50"}],"useCases":["Programmatic access to an x402-gated service payable in USDC on Base","Agent-driven API consumption without API keys or subscriptions","Demonstrating x402 protocol payment flows"],"bestFor":["Developers experimenting with x402 payment protocol","Agents that can negotiate x402 challenges on Base","Users who want keyless, pay-per-request API access"],"notFor":["Anyone needing documented input/output schemas before integrating","Use cases requiring guaranteed SLAs or support"],"kindDetails":{"x402_version":1,"resource_type":"http","bazaar_last_updated":"2026-02-17T23:15:01.455Z"},"updatedAt":"2026-04-23T05:00:37.084Z"}}