{"id":"47931c83-9373-4c1a-b339-89f002f5b92f","shortId":"fRJjZ4","kind":"x402","title":"x402-gated premium API access on Base, pay $0.02 per request in USDC — no API keys required.","tagline":"x402-gated premium API access on Base, pay $0.02 per request in USDC — no API keys required.","description":"lowpaymentfee.com offers a suite of pay-per-call API endpoints gated by the x402 protocol on the Base network. The specific endpoint at `/api/v1/charges/31` is labeled \"Premium API Access\" and returns a 402 challenge requesting payment in USDC (contract 0x8335…2913 on Base). The maximum amount required per call is 20,000 base units of USDC (6 decimals), which equals $0.02 USD. Payment is made via the x402 exact scheme by including an X-PAYMENT header with each request.\n\nThe broader lowpaymentfee.com 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 (geocoding, validation, conversion, generation). All endpoints are listed at the same $0.02/request price point. The platform emphasizes no API keys, no rate limits, no minimums, and instant access.\n\nHowever, the specific functionality behind `/api/v1/charges/31` (\"Premium API Access\") is not documented — it is unclear which of the above services this particular charge ID maps to, or whether it is a distinct endpoint. The docs, pricing, and API pages all returned only a \"Connect wallet\" prompt with no further documentation. There is no OpenAPI spec, no request/response schema, and no usage examples available from the crawl.","tags":[],"capabilities":["x402-payment","usdc-base","pay-per-request","no-api-key","http-post"],"categories":["api-gateway","misc"],"synonyms":["x402 API","pay-per-call API","USDC micropayment API","Base network API","lowpaymentfee","402 payment API","crypto-gated endpoint"],"warnings":["The specific functionality behind /api/v1/charges/31 ('Premium API Access') is not documented — it is unclear what data or service it provides.","No OpenAPI spec, request schema, or response schema is available.","All documentation pages (docs, pricing, API, README) returned only a 'Connect wallet' prompt with no usable content.","The platform lists many endpoint categories but none are individually documented with schemas or examples."],"endpointUrl":"https://lowpaymentfee.com/api/v1/charges/31","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/charges/31","description":"Premium API Access","outputSchema":{"input":{"type":"http","method":"GET","discoverable":true}},"maxAmountRequired":"20000","maxTimeoutSeconds":300}]},"qualityScore":"0.350","qualityRationale":"The endpoint is live and returns a valid x402 402 challenge, confirming pricing and payment details. However, there is no documentation, no OpenAPI schema, no request/response examples, and the specific functionality of /api/v1/charges/31 is undefined. The docs pages are empty beyond a wallet-connect prompt. 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":"2026-04-19T03:54:07.887Z","embedding":[-0.016082764,-0.038238525,0.043762207,0.018203735,0.011604309,-0.032684326,-0.02848816,0.026062012,0.06311035,-0.06951904,0.04272461,-0.040740967,-0.028656006,-0.017562866,-0.035827637,-0.0031051636,-0.017700195,0.006881714,-0.059173584,0.038848877,0.03970337,-0.011276245,-0.015403748,0.041290283,-0.00422287,-0.013557434,0.010231018,-0.019470215,-0.015655518,-0.015068054,0.019210815,-0.02418518,-0.010627747,0.011772156,-0.012458801,-0.021224976,-0.018295288,0.049041748,0.036834717,-0.007484436,0.0066833496,-0.0473938,0.0010519028,-0.0055274963,-0.049438477,-0.0057868958,0.013381958,-0.025405884,-0.030456543,0.0007953644,-0.034698486,-0.005050659,-0.015472412,0.0071983337,0.019515991,0.022399902,-0.019622803,-0.009635925,0.0074386597,0.009399414,-0.012367249,-0.06549072,-0.020141602,0.008361816,0.011062622,0.051940918,-0.012001038,0.048736572,0.0151901245,0.0574646,0.036346436,0.058685303,0.049865723,0.0074157715,0.0072517395,-0.002035141,-0.0025177002,0.044403076,-0.011177063,0.00032162666,-0.01737976,-0.01071167,-0.051208496,-0.0007157326,-0.023498535,-0.04345703,-0.015205383,0.019302368,-0.020141602,0.020950317,-0.07489014,-0.00018811226,-0.026138306,0.0047912598,-0.0003888607,0.0132751465,0.00019264221,0.025131226,-0.01461792,0.013130188,0.006690979,-0.043914795,0.020751953,0.02784729,0.056915283,0.042755127,0.017974854,0.038970947,-0.00983429,-0.02331543,-0.004711151,0.011245728,-0.028686523,-0.012008667,0.022460938,0.0012578964,-0.022903442,0.018081665,-0.03189087,0.02078247,-0.06021118,0.042236328,0.041229248,-0.031051636,0.016189575,-0.029312134,-0.01725769,0.0017633438,-0.03515625,-0.01838684,0.02017212,0.013305664,0.0390625,-0.028076172,-0.018417358,0.0035552979,-0.010528564,-0.031036377,-0.05606079,-0.01878357,0.042144775,-0.026626587,0.032348633,0.035949707,-0.095825195,-0.001285553,-0.049865723,0.0050239563,-0.036315918,-0.009925842,-0.020843506,0.032806396,-0.015464783,-0.0158844,-0.013946533,-0.01637268,-0.0051612854,0.03729248,-0.0029697418,0.042419434,-0.019760132,0.023757935,0.009849548,0.0014343262,0.024414062,0.03463745,-0.0038852692,-0.07623291,-0.0793457,-0.031143188,-0.011993408,-0.01322937,-0.04360962,-0.0065574646,0.0011014938,-0.08099365,-0.036834717,0.0032463074,-0.0013484955,-0.026748657,-0.012031555,-0.02519226,0.014083862,-0.014190674,-0.0657959,-0.0158844,-0.011688232,0.0657959,0.011627197,0.01461792,0.02470398,-0.013374329,0.068359375,0.018676758,-0.026901245,-0.02607727,0.024032593,-0.016983032,0.033996582,0.006690979,0.009262085,-0.044067383,0.037750244,0.045288086,0.013191223,-0.019470215,0.010414124,-0.05407715,-0.03463745,-0.04006958,0.005142212,0.0039100647,-0.009994507,0.040008545,-0.0335083,-0.03942871,0.0047073364,-0.0022735596,0.026794434,0.06185913,0.0030078888,-0.014038086,-0.001493454,0.015434265,-0.045288086,0.040740967,0.035308838,0.020599365,-0.025039673,-0.015464783,0.016921997,0.038238525,-0.037628174,-0.009460449,-0.026107788,0.009124756,0.014671326,-0.003955841,0.04156494,-0.022735596,-0.03186035,-0.023208618,-0.004585266,0.026626587,0.0057640076,-0.04824829,-0.047332764,-0.066223145,0.039916992,0.05014038,0.025131226,0.007499695,0.015777588,-0.027511597,-0.011138916,-0.06970215,0.06536865,0.07550049,-0.0077590942,-0.021224976,0.028656006,-0.015335083,-0.028244019,-0.010932922,-0.004508972,-0.017059326,-0.022476196,0.02154541,-0.036193848,0.0071640015,0.022155762,0.020950317,0.06210327,-0.021820068,-0.049224854,-0.03543091,0.005203247,0.0011091232,-0.015136719,0.00067567825,-0.011390686,0.015464783,0.021469116,-0.00756073,0.03062439,0.0029678345,0.02458191,-0.0042304993,-0.018295288,-0.024887085,-0.024642944,0.014083862,-0.015472412,-0.076293945,0.012306213,0.010353088,0.050476074,-0.0423584,0.04724121,-0.0060653687,0.004989624,0.05871582,-0.022628784,-0.037200928,-0.0021591187,0.02684021,0.035858154,0.04171753,0.0110321045,-0.010986328,-0.004184723,0.06188965,-0.014160156,-0.000047802925,0.005580902,0.014190674,0.024780273,0.010299683,-0.0692749,-0.038208008,-0.009437561,-0.03237915,0.02178955,-0.03918457,0.028717041,-0.007648468,0.0056381226,-0.008300781,0.008514404,-0.043426514,0.012580872,-0.014053345,0.0039978027,-0.024246216,-0.022064209,0.02142334,0.019470215,-0.020492554,0.00018525124,0.021865845,0.027954102,-0.0050849915,-0.03845215,-0.010253906,-0.016204834,0.0035743713,0.022338867,0.018066406,0.018859863,0.038330078,-0.03692627,0.021499634,0.026641846,0.020324707,0.03488159,-0.022705078,0.014953613,-0.04840088,-0.05307007,-0.015686035,-0.044036865,0.037628174,0.009033203,0.009063721,0.038238525,0.006626129,-0.022720337,-0.035369873,0.024749756,-0.04373169,0.0030460358,0.025604248,-0.010887146,-0.041229248,0.0015335083,0.012779236,0.00217247,0.035614014,0.0141067505,0.0018949509,0.056610107,0.035247803,0.013343811,0.02406311,0.025650024,0.027832031,-0.0063591003,-0.03579712,-0.02772522,-0.0064964294,0.022491455,-0.02015686,-0.017593384,-0.07385254,0.042175293,0.032684326,0.08477783,0.019317627,0.011116028,0.02217102,-0.011054993,0.015991211,-0.032470703,-0.023803711,-0.030181885,-0.04055786,0.034729004,-0.007835388,-0.005619049,-0.032806396,0.03781128,0.022705078,0.014053345,-0.032073975,0.064819336,-0.0031585693,-0.024551392,0.02293396,0.010673523,0.043273926,0.06933594,-0.054351807,0.030212402,0.020935059,-0.027389526,-0.009490967,0.039398193,0.0012779236,-0.010437012,-0.06933594,-0.030517578,-0.0025291443,-0.01965332,-0.06738281,0.0021400452,0.012634277,0.0262146,0.013381958,-0.014724731,-0.035217285,0.0020103455,-0.023849487,-0.045074463,0.00013887882,-0.039764404,0.012825012,0.039276123,-0.02859497,0.0015954971,0.0004248619,-0.007396698,0.0037212372,0.016921997,-0.00674057,-0.003320694,-0.05130005,0.018051147,0.007785797,0.008575439,0.01939392,0.027114868,0.036071777,0.026275635,0.057373047,0.007633209,-0.01576233,-0.061584473,0.01436615,-0.041900635,0.003036499,0.001168251,-0.017684937,-0.00598526,-0.019866943,-0.02027893,-0.018859863,0.0019512177,-0.03604126,0.010185242,0.02330017,-0.03491211,-0.028793335,-0.05090332,-0.014480591,-0.004501343,0.068481445,0.032684326,-0.0052757263,-0.06549072,-0.019454956,0.018493652,0.0071144104,0.009757996,-0.016189575,-0.015586853,-0.0066604614,-0.036010742,-0.028381348,-0.026473999,0.02848816,-0.009017944,-0.024642944,0.023086548,-0.012672424,0.01663208,-0.005897522,0.013549805,0.032226562,-0.025863647,-0.011894226,-0.03451538,0.012664795,0.003206253,-0.0030059814,-0.047943115,0.04574585,0.022567749,0.035949707,-0.03729248,-0.00223732,-0.0051574707,0.017501831,0.023605347,-0.01473999,-0.010902405,0.008766174,-0.037719727,-0.07104492,0.03086853,-0.032928467,0.028182983,0.00028157234,0.004146576,0.030456543,-0.009262085,0.007751465,0.024978638,-0.029724121,0.000099122524,-0.025222778,-0.04135132,-0.012321472,0.008972168,-0.009918213,0.018844604,-0.02420044,0.014656067,-0.01146698,-0.021621704,0.033996582,0.009048462,-0.0018320084,0.024749756,0.00062704086,0.017089844,0.05105591,0.008323669,-0.032440186,0.019714355,-0.0010662079,0.0048599243,-0.009010315,0.04296875,0.017730713,-0.02079773,-0.006713867,-0.008773804,-0.0135650635,-0.024765015,-0.01600647,0.020507812,0.039978027,0.008666992,-0.039276123,0.02558899,0.017700195,-0.03250122,-0.008140564,0.019302368,0.023666382,-0.030136108,0.028961182,0.03164673,0.050628662,-0.025344849,-0.0062294006,0.009918213,0.0259552,0.01977539,0.022827148,-0.021530151,0.010345459,-0.018859863,0.009468079,-0.0052986145,-0.0103302,0.010482788,-0.008712769,0.01625061,0.028961182,0.025238037,-0.020248413,-0.03111267,0.009025574,-0.010543823,-0.0124053955,0.022720337,0.016799927,0.011924744,-0.012969971,0.024810791,0.022323608,-0.037078857,-0.018203735,-0.012504578,0.04660034,-0.018341064,-0.010147095,0.013908386,0.0035858154,0.04006958,-0.052825928,0.00248909,0.008140564,0.0181427,-0.017333984,-0.03878784,-0.037384033,0.00497818,0.03567505,0.008796692,0.0067481995,0.032104492,-0.0012874603,0.01096344,0.016143799,-0.0010614395,-0.016342163,-0.008430481,-0.047180176,-0.0070762634,-0.017440796,-0.0065574646,-0.030212402,0.012680054,-0.021713257,-0.040740967,0.0021896362,-0.017196655,-0.003419876,0.0001257658,0.022598267,0.03778076,0.00356102,0.014343262,-0.013946533,-0.018417358,0.017120361,-0.008872986,0.028869629,-0.03866577,0.011894226,-0.015487671,-0.007041931,-0.0034637451,-0.0030937195,0.024230957,0.02015686,0.0025920868,0.03010559,-0.0473938,0.04751587,-0.028930664,0.017410278,-0.001241684,-0.04156494,-0.011405945,-0.026428223,-0.024871826,0.033050537,-0.026046753,0.002368927,-0.023468018,-0.019424438,-0.0055160522,-0.043273926,0.021026611,0.033050537,0.03866577,-0.027008057,-0.00434494,0.0025634766,0.0020198822,-0.015380859,0.0014104843,-0.01789856,0.0155181885,0.0143966675,0.006828308,-0.028717041,-0.02357483,-0.009246826,0.000787735,-0.052246094,-0.04675293,-0.020889282,0.01979065,-0.008041382,-0.013046265,-0.019699097,-0.018463135,0.0029563904,-0.03286743,0.011428833,0.010047913,0.030654907,0.0078048706,-0.017868042,0.007572174,0.025360107,-0.02029419,0.035217285,0.006969452,-0.010292053,-0.039489746,-0.0025634766,0.035827637,0.024124146,-0.0020427704,-0.0116119385,-0.008872986,-0.023101807,-0.05206299,-0.002670288,-0.016937256,-0.0009889603,0.0029735565,0.0020065308,-0.052581787,-0.012779236,-0.017929077,0.006801605,0.020019531,0.012573242,0.024276733,-0.008460999,0.0056610107,-0.010871887,-0.005554199,-0.035217285,0.012992859,0.012069702,-0.0039367676,0.0037250519,0.03665161,0.009521484,-0.013298035,0.000579834,-0.0020923615,0.019454956,-0.029800415,0.011077881,-0.014808655,0.014884949,-0.0046043396,-0.012840271,-0.037963867,-0.008590698,0.08343506,-0.0036735535,-0.007843018,-0.0032997131,-0.008346558,0.015312195,0.022491455,-0.054229736,-0.0135269165,-0.03945923,0.02204895,-0.021850586,0.020767212,0.001742363,0.013999939,-0.02835083,-0.06561279,-0.015586853,0.019989014,-0.0048828125,-0.051574707,-0.011306763,-0.04699707,-0.009689331,-0.009712219,-0.01927185,-0.009437561,0.013168335,-0.019073486,-0.08105469,0.01398468,0.052368164,0.015106201,0.020980835,-0.0149002075,0.01927185,0.03250122,-0.018844604,-0.016799927,0.027923584,-0.01499939,-0.018417358,-0.01737976,0.030838013,-0.013343811,-0.029067993,0.021728516,0.014816284,0.022613525,-0.002067566,0.0064315796,-0.013687134,0.013900757,-0.012084961,0.010818481,-0.0041503906,-0.008163452,0.024169922,-0.043884277,0.031188965,0.007827759,-0.000038146973,-0.0064735413,0.022033691,0.03488159,-0.039733887,-0.023651123,0.042114258,-0.0005927086,0.043792725,-0.03878784,0.05392456,0.027862549,-0.022598267,0.019210815,-0.013710022,-0.03579712,-0.031219482,-0.034240723,0.01360321,0.027557373,0.015853882,-0.011444092,-0.0022449493,0.023284912,-0.00969696,0.007820129,-0.01285553,-0.017837524,-0.007129669,0.012466431,0.0005221367,0.009475708,-0.010292053,0.018951416,0.021240234,0.048736572,-0.0005760193,-0.003030777,0.007381439,0.022644043,-0.023101807,0.009651184,0.004600525,0.014877319,0.021316528,0.020950317,0.009002686,-0.030792236,-0.019729614,-0.020370483,-0.008201599,0.002254486,0.005458832,-0.0054855347,0.0012683868,-0.0007786751,-0.011360168,-0.045043945,0.015823364,-0.028549194,-0.02609253,0.006576538,-0.008979797,0.013168335,0.007144928,-0.00050497055,0.011779785,0.003944397,0.056549072,-0.002456665,-0.001625061,0.016479492,0.030044556,0.011909485,-0.03857422,-0.010292053,-0.009338379,-0.0084991455,0.0043792725,-0.016403198,0.014038086,0.04534912,-0.007156372,0.01612854,-0.0118255615,0.015594482,0.008956909,0.006668091,-0.013412476,-0.0010156631,-0.018127441,0.035736084,-0.048309326,0.018814087,0.01878357,0.009346008,-0.007926941,-0.023025513,-0.02696228,0.008216858,0.010597229,-0.014289856,0.059509277,-0.008491516,0.030136108,-0.0178833,-0.029632568,0.015991211,-0.033416748,-0.01763916,0.045288086,-0.0062675476,-0.00067424774,0.016601562,-0.02848816,0.0345459,-0.037719727,0.02067566,-0.007888794,-0.004802704,-0.010131836,-0.01890564,-0.02128601,-0.013771057,-0.013046265,0.012763977,0.0013189316,0.03982544,0.031036377,0.026641846,0.036315918,0.029754639,0.006565094,-0.04257202,-0.01928711,-0.0034275055,-0.034301758,0.022857666,-0.0143585205,0.031188965,0.04034424,-0.0037021637,0.038879395,0.04815674,0.029449463,-0.0011138916,0.014953613,-0.016036987,0.014656067,-0.0009493828,0.036956787,0.007736206,0.033996582,-0.02999878,0.012519836,-0.004638672,0.032684326,-0.027511597,0.024002075,0.07305908,0.026885986,-0.0124053955,0.042999268,-0.0006108284,-0.010093689,-0.020523071,-0.012527466,0.066589355,0.018249512,0.04638672,0.05014038,0.021316528,-0.01789856,0.017120361,-0.023956299,-0.044647217,0.059753418,0.024749756,-0.023117065,-0.008888245,-0.008308411,0.01335144,-0.05557251,-0.019302368,0.025238037,-0.0013141632,0.015174866,-0.01374054,-0.0043754578,-0.010002136,0.016830444,0.013023376,0.01473999,-0.016021729,0.009719849,0.018295288,0.0129470825,0.02128601,0.0020427704,0.020629883,-0.029769897,-0.010536194,0.0049972534,0.016693115,-0.012535095,0.0028209686,0.02482605,0.021774292,0.04272461,0.034698486,-0.017227173,-0.001420021,0.029632568,0.023254395,-0.004070282,0.047332764,0.033996582,0.015007019,0.036712646,0.04397583,0.026626587,-0.030532837,0.015571594,0.00025749207,0.016921997,0.002122879,-0.012664795,0.0064849854,-0.008308411,0.008224487,0.0013418198,-0.011650085,0.028930664,0.030670166,-0.003944397,0.0001013875,-0.009780884,-0.0020923615,0.0014247894,0.0005264282,0.0039138794,-0.019195557,0.021255493,0.0035743713,0.030929565,-0.026657104,0.019851685,-0.004875183,-0.027709961,-0.009117126,0.009521484,-0.03692627,0.0019607544,-0.0046958923,-0.0036201477,-0.032592773,0.008613586,0.025115967,-0.00035119057,0.028793335,0.019424438,0.00020360947,-0.00566864,0.019180298,0.010513306,-0.010559082,-0.014411926,-0.01184845,0.037322998,0.041503906,-0.0024795532,0.014556885,-0.015396118,-0.0049972534,0.0057678223,-0.0037326813,0.0050582886,-0.0021591187,-0.0112838745,-0.029968262,0.01626587,0.043701172,0.020950317,0.03475952,-0.004508972,-0.024520874,0.007888794,0.029205322,0.006877899,0.005264282,-0.012382507,0.020614624,-0.0018844604,0.043121338,0.031982422,0.0049209595,0.027923584,-0.018692017,-0.007381439,0.012069702,-0.018920898,0.026824951,-0.016799927,0.008201599,-0.023330688,0.025253296,-0.022750854,-0.03475952,0.008888245,-0.013206482,-0.01625061,-0.02772522,0.0077590942,0.0037841797,0.018066406,0.034423828,0.021377563,-0.021881104,0.06762695,-0.008796692,0.055847168,-0.007019043,-0.0038452148,0.052734375,0.04812622,0.038909912,0.018371582,0.0090408325,-0.028930664,0.010902405,0.03793335,0.033721924,0.0013837814,0.0017948151,-0.006690979,0.028869629,-0.01210022,0.015434265,-0.015991211,0.0032138824,0.008964539,-0.011161804,-0.014015198,-0.0011339188,-0.003238678,0.020584106,0.04928589,-0.035003662,-0.015899658,-0.030319214,-0.009223938,0.027923584,-0.0048942566,-0.0019359589,-0.0039138794,-0.01146698,0.013870239,-0.02507019,-0.020996094,0.015960693,0.025497437,-0.045043945,-0.019699097,-0.0013465881,0.023651123,-0.028457642,0.02684021,0.020645142,-0.0072402954,0.011917114,0.05065918,-0.0045318604,0.034576416,-0.0014314651,0.019622803,0.033355713,0.0033874512,-0.0236969,-0.0013093948,0.0015764236,-0.0062713623,0.012237549,0.040740967,-0.009208679,0.013122559,0.001789093,-0.020904541,-0.0000026226044,0.010253906,-0.01550293,0.011619568,-0.0044555664,-0.014587402,0.0026607513,0.0016336441,0.0077171326,0.0023918152,-0.0065574646,-0.006210327,-0.008300781,0.030044556,0.010932922,-0.045288086,-0.0047683716,0.013771057,0.019592285,-0.029281616,-0.031341553,-0.018417358,-0.03100586,0.013549805,0.015312195,0.011421204,0.004501343,-0.021911621,-0.0002373457,0.02748108,0.004737854,0.023284912,0.0025081635,-0.0104522705,0.005683899,-0.021102905,-0.0018520355,-0.0024642944,-0.0020389557,0.0107803345,0.0053901672,-0.0017929077,-0.034179688,0.016647339,0.00044941902,0.011978149,0.0031585693,-0.014556885,0.024307251,-0.010215759,-0.009513855,0.009971619,0.012680054,-0.011657715,-0.013114929,-0.028717041,0.03289795,0.05697632,-0.0058021545,-0.008232117,0.012626648,0.016723633,0.025772095,0.038879395,0.01763916,0.039611816,0.016464233,-0.011146545,-0.02507019,0.028518677,-0.0065956116,-0.036193848,0.020767212,-0.006259918,-0.0155181885,0.019958496,0.01889038,-0.008995056,-0.023635864,-0.021057129,-0.019042969,-0.012008667,0.022613525,-0.0234375,0.014205933,-0.029754639,-0.012496948,0.016906738,-0.021499634,-0.045715332,-0.03353882,-0.0072250366,-0.013320923,-0.053375244,0.011566162,-0.029724121,0.008140564,-0.02571106,-0.0013628006,-0.0065345764,0.03353882,-0.005710602,0.0014705658,0.01133728,0.027404785,0.0034694672,0.016036987,0.012207031,-0.029067993,-0.024414062,-0.0211792,-0.0014152527,-0.012420654,0.018188477,-0.0017738342,0.030212402,0.009895325,-0.008605957,0.003540039,-0.008918762,0.0011510849,-0.0005965233,-0.040405273,-0.022857666,0.011856079,0.029632568,-0.016860962,-0.0149383545,0.048065186,-0.020324707,-0.013809204,0.014984131,0.04336548,0.01436615,0.028869629,-0.01852417,-0.012840271,-0.016555786,-0.00078344345,-0.0178833,0.0035896301,0.016296387,0.0018672943,0.0017995834,-0.00018954277,0.015945435,-0.016418457,-0.0040779114,0.026367188,0.0034713745,-0.029037476,0.041748047,0.012969971,0.0017671585,-0.0037460327,-0.010169983,0.017700195,0.048858643,0.0036087036,0.008255005,-0.0019311905,0.0065231323,-0.014884949,0.020263672,0.01361084,-0.02407837,-0.03503418,-0.027740479,-0.023757935,0.0141067505,0.004550934,0.024337769,0.0024471283,0.013908386,-0.020935059,-0.022094727,-0.032165527,0.020751953,-0.01499939,-0.012931824,-0.0076828003,0.013824463,0.020614624,-0.03829956,0.0022792816,-0.04083252,-0.016830444,-0.010559082,-0.02859497,0.017181396,0.010147095,-0.007701874,0.004184723,-0.0064926147,-0.011505127,0.0046195984,0.032287598,-0.019195557,0.0048713684,0.022628784,0.010688782,-0.02696228,0.014053345,-0.0058937073,-0.009475708,0.017929077,-0.013771057,0.0155181885,-0.018936157,0.030380249,0.009475708,-0.0038146973,0.036071777,0.00006341934,0.009483337,-0.01701355,-0.008178711,-0.0006451607,-0.00831604,0.039611816,-0.011520386,-0.025680542,0.010971069,-0.021896362,-0.034851074,0.0069465637,0.028518677,0.04043579,-0.018356323,0.03652954,-0.016082764,-0.018295288,0.012420654,0.013259888,-0.016952515,0.0021038055,0.036712646,0.010383606,-0.00025558472,0.0050582886,-0.012557983,-0.03152466,-0.00932312,0.02418518,-0.007347107,-0.0141067505,0.021194458,0.009857178,0.045715332,0.000893116,0.020385742,0.026184082,0.00066900253,0.030044556,-0.0026416779,0.05105591,-0.0011396408,-0.036712646,0.0035896301,0.0012426376,-0.018234253,-0.009407043,0.0023727417,0.0030651093,-0.040802002,0.011917114,0.00066137314,0.04321289,-0.02532959,0.011955261,-0.018417358,-0.0042152405,-0.0317688,0.0022945404,-0.032226562,0.016662598,0.036865234,0.012588501,0.011245728,0.0055389404,-0.028717041,0.029876709,0.04284668,-0.0053596497,-0.022460938,-0.0079574585,0.017120361,-0.0027427673,-0.002286911,0.021270752,-0.025619507,-0.010520935,0.003522873,-0.02571106,0.008979797,-0.0029468536,0.019210815,0.0011262894,-0.012069702,-0.0037631989,0.025543213,0.008262634,-0.008491516,0.0062332153,0.00894928,0.038238525,0.04006958,-0.008613586,0.016555786,0.025970459,-0.031402588,0.0501709,-0.013771057,0.023773193,-0.025131226,0.013206482,-0.034088135,-0.0031032562,-0.0073127747,0.011291504],"createdAt":"2026-04-18T18:45:04.304Z","updatedAt":"2026-04-22T09:01:01.761Z","lastSeenAt":"2026-04-22T09:01:01.761Z","tsv":"'/api/v1/charges/31':61,189 '/request':167 '0.02':10,28,98,166 '000':89 '0x8335':77 '20':88 '2913':78 '402':70 '402 payment API' '6':94 'Base network API' 'USDC micropayment API' 'access':6,24,66,183,192 'across':124 'advertis':122 'ai':134 'amount':83 'analysi':138 'analyt':128 'api':5,16,23,34,46,65,174,191,221 'avail':246 'base':8,26,55,80,90 'behind':188 'broader':119 'call':45,86 'categori':126 'challeng':71 'charg':206 'classif':141 'connect':227 'contract':76 'convers':157 'crawl':249 'crypto-gated endpoint' 'data':127,131 'decim':95 'distinct':215 'doc':218 'document':195,233 'embed':142 'emphas':172 'endpoint':47,59,123,160,216 'equal':97 'estim':152 'exact':106 'exampl':245 'exchang':147 'export':132 'feed':146 'financ':143 'four':125 'function':187 'gas':151 'gate':3,21,48 'generat':158 'geocod':155 'header':114 'howev':184 'http-post' 'id':207 'includ':109 'infrastructur':154 'insight':133 'instant':182 'key':17,35,175 'label':63 'learn':136 'limit':178 'list':162 'lowpaymentfee' 'lowpaymentfee.com':37,120 'machin':135 'made':102 'map':208 'maximum':82 'metric':129 'minimum':180 'network':56 'no-api-key' 'offer':38 'openapi':237 'page':222 'particular':205 'pay':9,27,43 'pay-per-cal':42 'pay-per-call API' 'pay-per-request' 'payment':73,100,113 'per':11,29,44,85 'platform':121,171 'point':169 'premium':4,22,64,190 'price':145,168,219 'prompt':229 'protocol':52 'quot':150 'rate':148,177 'report':130 'request':12,30,72,117 'request/response':240 'requir':18,36,84 'return':68,224 'schema':241 'scheme':107 'sentiment':137 'servic':203 'spec':238 'specif':58,186 'suit':40 'summar':140 'text':139 'token':149 'unclear':198 'unit':91 'usag':244 'usd':99 'usdc':14,32,75,93 'usdc-base' 'valid':156 'via':103 'wallet':228 'web3':144 'whether':211 'x':112 'x-payment':111 'x402':2,20,51,105 'x402 API' 'x402-gated':1,19 'x402-payment'","prices":[{"id":"b98f2215-f10e-4d86-a91a-e4b0666c3a43","listingId":"47931c83-9373-4c1a-b339-89f002f5b92f","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/charges/31","description":"Premium API Access","outputSchema":{"input":{"type":"http","method":"GET","discoverable":true}},"maxAmountRequired":"20000","maxTimeoutSeconds":300}],"asset_contract":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","max_timeout_seconds":300},"createdAt":"2026-04-18T18:45:04.304Z"}],"sources":[{"listingId":"47931c83-9373-4c1a-b339-89f002f5b92f","source":"x402_bazaar","sourceId":"https://lowpaymentfee.com/api/v1/charges/31","sourceUrl":"https://api.cdp.coinbase.com/platform/v2/x402/discovery/resources","isPrimary":true,"firstSeenAt":"2026-04-18T18:45:04.304Z","lastSeenAt":"2026-04-22T09:01:01.761Z"}],"details":{"listingId":"47931c83-9373-4c1a-b339-89f002f5b92f","quickStartSnippet":"# Send a POST with x402 payment header to access the endpoint\ncurl -X POST https://lowpaymentfee.com/api/v1/charges/31 \\\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/charges/31"},{"claim":"USDC contract address on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","source_url":"https://lowpaymentfee.com/api/v1/charges/31"},{"claim":"Platform advertises $0.02/request pricing with no API keys, no rate limits, and instant access","source_url":"https://lowpaymentfee.com"},{"claim":"Platform lists endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categories","source_url":"https://lowpaymentfee.com"}],"useCases":["Accessing premium API services with per-request USDC micropayments on Base","Agent-driven API consumption without pre-registration or API key management","Programmatic pay-as-you-go access to data, AI, finance, or utility endpoints"],"bestFor":["Developers or agents wanting keyless, pay-per-use API access","x402-compatible clients on the Base network","Low-volume or exploratory API usage at $0.02/call"],"notFor":["Users who need detailed API documentation or guaranteed SLAs before purchasing","High-volume consumers who need bulk pricing or rate-limit guarantees","Users without USDC on Base or an x402-compatible payment client"],"kindDetails":{"x402_version":1,"resource_type":"http","bazaar_last_updated":"2026-02-17T23:14:22.617Z"},"updatedAt":"2026-04-22T09:01:01.761Z"}}