{"id":"47004673-5656-49d8-81f2-7bf716b182dd","shortId":"YAAWQy","kind":"x402","title":"Pay-per-call API platform on Base (USDC) offering data, AI, finance, and utility endpoints at $0.02/request.","tagline":"Pay-per-call API platform on Base (USDC) offering data, AI, finance, and utility endpoints at $0.02/request.","description":"lowpaymentfee.com is an x402-enabled API platform that provides a broad catalog of pay-per-request endpoints settled in USDC on the Base network. The specific endpoint at `/api/v1/inbox/22` is listed as \"Premium API Access\" and costs up to $0.02 per call (20,000 base units of USDC with 6 decimals). Payment is handled via the x402 protocol — no API keys, accounts, or subscriptions are required; callers simply attach an X-PAYMENT header with a valid payment proof.\n\nThe wider platform advertises four endpoint 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). All endpoints are listed at the same $0.02/request price point.\n\nHowever, the specific functionality of the `/api/v1/inbox/22` endpoint is unclear. The path pattern (\"inbox/22\") does not match any of the documented API categories, and the description is simply \"Premium API Access\" with no further detail. There is no OpenAPI spec, no request/response schema documentation, and the crawled docs pages (pricing, README, API) all returned only a \"Connect wallet\" prompt with no additional content. Prospective callers should be aware that the actual behavior of this particular endpoint is undocumented.","tags":[],"capabilities":["x402-payment","usdc-settlement","base-network","pay-per-request","no-api-key","post-endpoint"],"categories":["api-platform","pay-per-use"],"synonyms":["x402 API","micropayment API","USDC pay-per-call","Base network API","lowpaymentfee","crypto API access","402 payment API"],"warnings":["The specific functionality of /api/v1/inbox/22 is completely undocumented — the path does not match any of the advertised API categories","No OpenAPI spec or request/response schema is available for any endpoint on this platform","Documentation pages (/pricing, /README, /api) returned only 'Connect wallet' with no useful content","The purpose of 'inbox/22' is unclear — it may be a generic or placeholder endpoint"],"endpointUrl":"https://lowpaymentfee.com/api/v1/inbox/22","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/inbox/22","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 it accepts USDC on Base at $0.02/request. However, there is no OpenAPI spec, no request/response schema, no documentation of what this specific endpoint actually does, and the path 'inbox/22' doesn't match any documented category. The listing is essentially a stub with confirmed liveness but unknown functionality.","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":"2026-04-21T21:37:38.211Z","embedding":[-0.023117065,-0.02029419,0.033569336,0.023132324,0.024047852,-0.034362793,-0.01927185,0.04321289,0.076293945,-0.07385254,0.018585205,-0.03717041,-0.019927979,-0.026260376,-0.019989014,0.0068092346,0.0014762878,0.0042915344,-0.046813965,0.026306152,0.012161255,0.0023002625,-0.04071045,0.035491943,-0.004589081,-0.033569336,-0.01777649,-0.018585205,-0.0024719238,-0.036102295,0.053985596,-0.027557373,0.0042152405,0.008644104,-0.016235352,-0.01638794,0.0063819885,0.0362854,0.028869629,-0.0041885376,-0.017532349,-0.046875,0.0049743652,-0.020217896,-0.052520752,-0.008377075,0.0026073456,-0.011314392,0.00046539307,0.0049858093,-0.03564453,-0.0044288635,-0.0022563934,0.013496399,0.026809692,0.009109497,0.007896423,-0.0021343231,0.015594482,0.018157959,-0.0013999939,-0.05657959,-0.03567505,-0.0050201416,-0.0020484924,0.03881836,-0.00047707558,0.05340576,-0.002670288,0.07122803,0.031799316,0.043823242,0.009422302,0.014625549,0.011146545,-0.0020809174,-0.0030994415,0.05328369,-0.016860962,-0.010696411,-0.019195557,-0.008811951,-0.05596924,-0.0016431808,-0.018112183,-0.038024902,-0.021499634,0.012588501,-0.036895752,0.012619019,-0.08203125,-0.022735596,-0.007896423,0.008575439,0.005420685,-0.02041626,0.003063202,0.012641907,-0.013725281,0.027770996,0.0015392303,-0.04537964,0.018478394,0.006515503,0.04220581,0.033081055,0.012870789,0.010437012,0.022521973,-0.015380859,-0.043304443,0.012336731,-0.030319214,-0.0082092285,-0.00541687,0.007499695,-0.0068626404,0.014846802,-0.03543091,0.012886047,-0.03793335,0.046783447,0.012428284,0.011451721,0.0026512146,-0.0496521,-0.009635925,0.013900757,-0.034088135,-0.012260437,0.02015686,0.013084412,0.014022827,-0.026351929,-0.053649902,-0.014045715,-0.030181885,-0.005508423,-0.039001465,-0.042053223,0.046020508,-0.035217285,0.024154663,0.01940918,-0.10467529,-0.012763977,-0.034362793,-0.008865356,-0.01751709,-0.004676819,-0.019851685,0.03555298,-0.01322937,-0.027877808,-0.015113831,-0.012664795,0.028762817,0.018508911,-0.021606445,0.05517578,-0.017730713,0.008308411,0.018615723,0.00012242794,0.0066184998,0.019256592,0.0005464554,-0.09259033,-0.07867432,-0.016830444,0.007698059,-0.014450073,-0.032318115,-0.0018959045,-0.009590149,-0.047180176,-0.0155181885,-0.014755249,0.0040626526,-0.04937744,0.011962891,-0.014312744,0.017791748,-0.026672363,-0.04623413,-0.018249512,-0.01398468,0.05053711,0.01309967,0.027404785,0.037872314,-0.026504517,0.06756592,0.047912598,-0.03717041,-0.02748108,0.010047913,-0.02331543,0.014732361,0.00037121773,0.004383087,-0.050933838,0.030151367,0.07696533,-0.002122879,0.004043579,-0.008995056,-0.039764404,-0.041992188,-0.028045654,0.032287598,0.009925842,-0.015464783,0.038726807,-0.039733887,-0.051239014,-0.030319214,0.0096206665,0.012519836,0.060516357,0.01940918,0.024032593,-0.0016002655,0.033966064,-0.0335083,0.031463623,0.025970459,-0.004486084,-0.033813477,-0.012634277,0.016067505,0.043426514,-0.005088806,0.0054473877,0.0024700165,0.02708435,-0.022644043,0.0069351196,0.02229309,0.011001587,-0.017684937,-0.0236969,-0.03173828,0.018692017,0.006023407,-0.02519226,-0.020935059,-0.07513428,0.05053711,0.029144287,0.048583984,0.0052948,-0.0033016205,-0.024719238,-0.003293991,-0.06317139,0.052368164,0.06329346,-0.004837036,-0.02180481,0.026565552,-0.015037537,-0.029251099,0.03314209,-0.0074768066,-0.042297363,-0.0070495605,0.00705719,-0.06341553,-0.010231018,-0.0017547607,0.034698486,0.056152344,0.004348755,-0.042266846,-0.018051147,-0.02267456,-0.031677246,-0.016983032,0.009536743,-0.026870728,-0.000055730343,0.017959595,-0.0049819946,0.018920898,-0.01108551,0.021514893,-0.0067863464,0.002626419,-0.025680542,-0.023803711,0.010093689,0.005302429,-0.046417236,-0.007396698,-0.02015686,0.081604004,-0.040222168,0.030151367,-0.0043678284,0.026229858,0.028259277,0.018249512,-0.048980713,0.0076789856,0.02571106,0.029830933,0.053863525,0.004005432,-0.034332275,-0.024719238,0.061950684,-0.018661499,-0.012008667,0.0045166016,-0.005508423,0.019363403,-0.017425537,-0.045440674,-0.027526855,-0.016113281,-0.023834229,0.018692017,-0.025680542,0.030975342,-0.0049858093,0.0115356445,-0.010978699,-0.005214691,-0.019744873,0.027359009,-0.051940918,-0.00050878525,-0.026016235,-0.025268555,0.021911621,0.008903503,0.0038433075,-0.012680054,0.02607727,0.025756836,-0.015991211,-0.040130615,-0.021484375,-0.023590088,-0.0011320114,0.010940552,0.02696228,0.025863647,0.045074463,-0.040863037,0.0036315918,0.04940796,0.013710022,0.03137207,-0.0031909943,0.010131836,-0.08947754,-0.055725098,-0.0234375,-0.035888672,0.0062179565,0.017669678,0.0049972534,0.03982544,0.0015745163,-0.03955078,-0.070617676,0.035491943,-0.05255127,0.020950317,0.04043579,-0.013343811,-0.029266357,-0.0055389404,-0.0016441345,0.0058517456,0.03152466,0.012062073,0.019439697,0.087768555,0.057525635,-0.014183044,0.018692017,0.024291992,0.024429321,0.0031795502,-0.019592285,-0.033172607,0.00042033195,0.028930664,-0.027130127,-0.027618408,-0.07574463,0.039123535,0.038116455,0.07598877,0.016815186,0.010688782,0.015899658,-0.003572464,0.00020170212,-0.03100586,-0.015586853,-0.031082153,-0.044403076,0.040252686,-0.025802612,0.0075302124,-0.028305054,0.045166016,-0.017425537,0.029296875,-0.020263672,0.035186768,-0.0115356445,0.009803772,0.016586304,0.013656616,0.04849243,0.07110596,-0.048797607,0.020996094,0.03793335,-0.021484375,0.008285522,0.044128418,-0.011703491,-0.0128479,-0.078552246,-0.040252686,0.0026836395,-0.010643005,-0.059387207,0.014259338,0.002319336,0.016052246,0.021957397,-0.01600647,-0.0016756058,-0.009803772,-0.025344849,-0.064208984,-0.003791809,-0.03717041,0.012962341,0.04171753,-0.025726318,-0.0061454773,-0.003250122,-0.02330017,-0.00075769424,0.010292053,0.023590088,0.00020992756,-0.042510986,0.027450562,0.011856079,-0.00088214874,0.01576233,0.032165527,-0.0067749023,0.025268555,0.060791016,0.0124053955,-0.020050049,-0.056671143,0.026184082,-0.050964355,0.017288208,0.011199951,-0.03552246,0.020080566,0.0057792664,-0.041778564,-0.029052734,0.012084961,-0.022537231,-0.012252808,0.016906738,-0.017059326,-0.019454956,-0.040618896,-0.015411377,0.019989014,0.073913574,0.01235199,0.007797241,-0.05960083,-0.004837036,0.008728027,0.003856659,0.04147339,-0.015113831,-0.019363403,-0.008125305,-0.038848877,-0.01939392,-0.017120361,0.031921387,0.0036849976,-0.0104522705,0.042663574,0.013183594,0.015556335,0.013420105,0.0022830963,0.019729614,-0.036712646,-0.023666382,0.005428314,0.05340576,0.005722046,-0.01398468,-0.04498291,0.029296875,0.019470215,0.037353516,-0.02041626,-0.01576233,-0.02053833,0.022232056,0.011222839,-0.017974854,-0.012954712,0.0074768066,-0.06744385,-0.061523438,0.036010742,-0.019683838,0.018112183,0.014846802,0.016525269,0.0055732727,-0.0052871704,0.015106201,0.014770508,-0.026138306,-0.0037631989,-0.017837524,-0.021697998,-0.011657715,-0.007183075,-0.0056152344,0.017959595,-0.010879517,0.012207031,0.005054474,-0.0042266846,0.032348633,-0.0016345978,0.004600525,0.030685425,0.006401062,0.024536133,0.03353882,0.0069351196,-0.045288086,0.028198242,-0.014198303,0.02607727,-0.012702942,0.041992188,0.04031372,0.013046265,-0.009292603,-0.009025574,-0.026901245,-0.018463135,0.0075645447,0.0018463135,0.015686035,-0.020263672,-0.058288574,0.023330688,0.011802673,-0.038391113,-0.034729004,0.014945984,0.009963989,-0.037353516,0.013244629,0.022705078,0.0597229,-0.032165527,0.024871826,0.01826477,0.038024902,0.035186768,0.0017747879,-0.011871338,0.014022827,-0.0071105957,0.009719849,0.0024795532,0.0009870529,0.026565552,-0.0005941391,0.030975342,0.037841797,0.02017212,-0.013496399,-0.03781128,0.0036716461,-0.008224487,-0.009094238,0.014183044,0.02583313,0.025146484,-0.03213501,0.015571594,0.007259369,-0.02128601,-0.0073242188,-0.019241333,0.029510498,-0.005859375,-0.010276794,0.02180481,0.009979248,0.021087646,-0.045074463,-0.0024662018,0.011665344,0.020690918,-0.017990112,-0.048034668,-0.04650879,0.010513306,0.014076233,0.00843811,0.027191162,0.03111267,-0.0024585724,-0.002632141,0.025665283,0.0105896,-0.032073975,-0.015716553,-0.031799316,-0.017044067,-0.015235901,0.00048971176,-0.033599854,0.01838684,-0.0014514923,-0.028396606,-0.008155823,-0.011451721,-0.00059747696,-0.007949829,-0.0019607544,0.045043945,0.0071258545,0.022491455,-0.0049552917,-0.025726318,-0.006099701,-0.010803223,0.030288696,-0.045318604,0.017349243,-0.004005432,0.0041618347,-0.0036029816,0.002090454,0.008140564,0.022369385,0.017166138,0.0335083,-0.04623413,0.05810547,-0.020217896,0.01612854,-0.0015983582,-0.026504517,0.0020542145,-0.023529053,-0.016433716,0.033813477,-0.0236969,-0.036315918,-0.023880005,-0.021118164,0.0017642975,-0.041259766,0.02897644,0.037078857,0.028625488,-0.032348633,0.014434814,0.010856628,0.005645752,-0.010650635,-0.0023536682,0.0075645447,0.010620117,0.02192688,0.00030350685,-0.016708374,-0.021575928,-0.02583313,-0.0039367676,-0.04043579,-0.060150146,-0.00046992302,0.016601562,0.0014476776,-0.023864746,-0.018966675,-0.03390503,0.0055885315,-0.03527832,0.006843567,-0.0037193298,0.01574707,-0.009437561,-0.041168213,0.013122559,0.021011353,-0.0003631115,0.03878784,0.01689148,0.0043525696,-0.026031494,0.024765015,0.022384644,0.0071105957,-0.0011167526,-0.012916565,-0.0063438416,-0.028335571,-0.064208984,-0.0051841736,-0.013755798,-0.01360321,-0.014198303,0.011070251,-0.0418396,0.010696411,0.0019330978,-0.0061187744,0.02116394,0.005455017,-0.007144928,-0.013389587,0.013916016,-0.0049552917,-0.021759033,-0.018798828,0.021240234,0.011650085,-0.0011196136,0.0340271,0.05078125,0.0014505386,-0.02809143,0.023956299,0.0088272095,0.021026611,-0.016326904,0.0030517578,-0.014045715,0.0039405823,-0.015113831,-0.012954712,-0.04425049,-0.0033340454,0.074279785,0.00036120415,0.004360199,-0.016113281,-0.013244629,0.009483337,0.020751953,-0.03894043,0.0011768341,-0.038909912,0.0020713806,-0.02758789,0.035369873,0.0059547424,0.023162842,-0.014419556,-0.047729492,-0.011245728,0.0055618286,-0.0025959015,-0.05355835,-0.011810303,-0.056152344,0.014701843,-0.0132751465,-0.040374756,0.00008499622,0.0058174133,-0.007045746,-0.089538574,0.010612488,0.038024902,0.0067100525,0.03074646,-0.001127243,0.020477295,0.01272583,-0.013145447,0.0018043518,0.027420044,-0.02961731,-0.017700195,-0.015167236,0.024093628,0.008766174,-0.025970459,0.021575928,0.008132935,0.024917603,-0.015197754,0.01940918,-0.00046110153,0.021392822,-0.035614014,0.020080566,-0.0128479,-0.010498047,0.033966064,-0.04534912,0.020339966,0.01197052,-0.0024280548,-0.0026607513,0.022354126,0.03414917,-0.024383545,-0.02041626,0.009880066,-0.0017757416,0.027664185,-0.026123047,0.048217773,0.020690918,-0.02796936,0.018508911,0.00037789345,-0.003932953,-0.03338623,-0.019104004,0.014877319,-0.008323669,0.015144348,-0.017288208,0.007896423,0.0115356445,-0.0143585205,0.020492554,-0.007205963,-0.02268982,-0.012519836,-0.006477356,0.005218506,0.010910034,0.00054216385,0.024017334,0.026626587,0.028503418,0.00047445297,-0.015220642,0.0024871826,0.022399902,0.003829956,0.011627197,0.03286743,0.017578125,0.0068626404,0.019119263,0.007331848,-0.046295166,0.0014438629,-0.014945984,-0.013664246,-0.0019950867,-0.01600647,-0.0074310303,-0.0074386597,0.006965637,-0.0135269165,-0.028518677,0.0055885315,-0.022354126,-0.026947021,-0.0052719116,-0.008384705,0.022460938,0.0022773743,-0.001616478,0.024673462,0.0060195923,0.040618896,-0.0051879883,-0.026901245,0.013031006,0.020950317,0.02116394,-0.034423828,-0.014450073,-0.00466156,0.011070251,0.0001373291,-0.036346436,0.0023994446,0.040100098,-0.011131287,0.011665344,-0.012817383,0.026504517,-0.009300232,0.025756836,-0.018966675,0.019134521,-0.008842468,0.018478394,-0.030151367,0.01939392,0.030654907,0.010391235,-0.009269714,-0.021774292,-0.037597656,0.023132324,0.010879517,-0.016647339,0.056518555,0.009742737,0.020126343,-0.021621704,-0.016586304,0.0035762787,-0.03463745,-0.027420044,0.035858154,0.0064582825,0.009353638,0.005039215,-0.030960083,0.033721924,-0.023452759,0.019729614,0.0015115738,-0.008758545,-0.011070251,-0.024505615,-0.0047187805,0.009902954,-0.030319214,-0.0013465881,0.00076150894,0.0670166,0.020950317,0.04434204,0.042144775,-0.00021529198,0.0009508133,-0.034576416,-0.030853271,0.0036888123,-0.023880005,0.012580872,-0.021575928,0.055023193,0.050628662,-0.012870789,0.033477783,0.050201416,0.035125732,-0.013008118,0.016601562,-0.02407837,-0.0032310486,0.0063095093,0.030639648,0.006275177,0.044830322,-0.024841309,0.028305054,0.029510498,0.023345947,-0.028045654,0.03213501,0.071899414,0.011940002,0.010482788,0.010192871,0.0022830963,-0.015975952,-0.00274086,-0.028839111,0.05303955,0.01322937,0.06951904,0.04360962,-0.0019216537,-0.011123657,0.018630981,-0.026611328,-0.011009216,0.0597229,0.009178162,-0.020309448,-0.0050468445,0.00762558,-0.0032100677,-0.046325684,-0.027038574,0.024871826,-0.0077590942,0.011253357,-0.007751465,-0.0002297163,-0.016113281,0.01826477,0.00920105,0.0047035217,0.0011396408,0.028442383,0.021408081,0.0059394836,0.03161621,-0.0031051636,0.021759033,-0.031463623,-0.02911377,0.009796143,0.012741089,-0.006362915,-0.008529663,0.033203125,-0.007030487,0.039978027,0.04269409,-0.015533447,0.0126953125,0.024658203,-0.0032863617,-0.0043563843,0.06976318,0.03010559,0.0071105957,0.03933716,0.023498535,0.043060303,-0.028503418,0.03567505,0.0031394958,0.0045204163,-0.0096206665,-0.022583008,-0.008720398,0.003030777,0.02142334,0.0030651093,-0.018035889,-0.0010080338,0.03616333,-0.006061554,0.0023536682,-0.0052452087,-0.010520935,-0.017181396,-0.0099487305,0.0058403015,-0.02293396,0.028015137,0.012954712,0.030899048,-0.009490967,0.0062179565,-0.00095558167,-0.014823914,-0.004272461,0.029373169,-0.025482178,0.011390686,0.0054740906,-0.013954163,-0.055603027,0.016296387,0.009635925,-0.0058288574,0.02897644,0.010536194,-0.018920898,0.013069153,0.006793976,0.0014543533,0.011451721,-0.013702393,-0.02218628,0.033416748,0.046325684,0.004131317,0.0037117004,-0.026428223,-0.009399414,0.006259918,-0.003921509,-0.022827148,-0.010055542,-0.005168915,-0.032470703,0.010910034,0.022964478,0.033813477,0.042907715,-0.009506226,-0.015426636,0.0031414032,0.019180298,0.008865356,0.008834839,0.009506226,0.0062217712,-0.00440979,0.036102295,0.044403076,0.01838684,0.045410156,-0.013465881,-0.004196167,0.0021343231,-0.014701843,0.008308411,-0.027359009,-0.0031967163,-0.010787964,0.03086853,-0.023834229,-0.03173828,0.010131836,-0.016967773,-0.026290894,-0.0129470825,0.008148193,0.005004883,0.034362793,0.042266846,0.017547607,-0.032318115,0.066101074,-0.020599365,0.053863525,-0.0007658005,-0.020004272,0.048950195,0.039398193,0.021118164,0.00894928,0.017486572,-0.04598999,0.01612854,0.043060303,0.026229858,0.020904541,-0.010734558,-0.011993408,0.033569336,-0.0022563934,0.0149002075,-0.008613586,-0.0017261505,0.01828003,-0.006801605,-0.0048065186,-0.00440979,0.004486084,0.004638672,0.039489746,-0.028076172,-0.012710571,-0.027145386,-0.011001587,0.033935547,-0.020477295,-0.0022735596,-0.0025939941,-0.023620605,0.004699707,-0.018341064,-0.025009155,-0.00024676323,0.020324707,-0.039154053,-0.025314331,0.009590149,-0.0022640228,-0.014144897,0.035583496,0.012565613,-0.016586304,0.014541626,0.032104492,-0.010307312,0.014717102,-0.028930664,0.02178955,0.034088135,0.011489868,-0.011451721,-0.0070724487,0.0012359619,-0.010139465,0.01600647,0.038879395,0.003370285,0.007297516,-0.0055122375,-0.016998291,0.0019664764,0.004058838,-0.005504608,0.002796173,-0.0082473755,-0.010299683,-0.0007748604,0.0077934265,0.0016241074,0.0031528473,-0.029647827,-0.018829346,0.012214661,0.05419922,0.029830933,-0.03842163,-0.013320923,-0.0017614365,0.010345459,-0.031311035,-0.008033752,-0.02218628,-0.02986145,0.01977539,0.020263672,0.012184143,0.02267456,-0.014755249,-0.0021686554,0.026031494,0.010246277,0.0126953125,0.0073928833,-0.01965332,-0.0020542145,-0.015090942,-0.0076789856,-0.015159607,-0.0020694733,0.006629944,0.022903442,0.0044898987,-0.028396606,0.021347046,-0.011909485,0.018722534,0.0006098747,0.003025055,0.016494751,-0.005996704,-0.013374329,-0.00069618225,0.008850098,-0.02041626,-0.00945282,-0.028869629,0.0075035095,0.044281006,-0.00440979,-0.0029716492,0.035614014,0.012664795,0.03074646,0.04324341,0.000012218952,0.048583984,0.02494812,-0.016448975,-0.02532959,0.014770508,-0.010482788,-0.0146865845,0.022094727,-0.017700195,-0.032989502,0.010314941,0.005138397,0.0021400452,-0.016601562,-0.0052719116,-0.013954163,-0.033599854,0.027420044,-0.016220093,0.021072388,-0.015792847,-0.007797241,0.00067186356,-0.027862549,-0.057434082,-0.02748108,0.0013046265,-0.0031642914,-0.07330322,0.006816864,-0.03857422,0.025375366,-0.017959595,-0.004386902,-0.018432617,0.023376465,-0.01436615,0.00579834,-0.002861023,0.025726318,0.01727295,0.02230835,0.027404785,-0.031143188,-0.04788208,-0.011734009,0.00055217743,-0.004623413,0.015594482,0.0095825195,0.03036499,0.016647339,-0.015144348,0.00026655197,-0.009048462,-0.0008401871,-0.018127441,-0.030975342,-0.023666382,0.017166138,0.016204834,-0.008575439,0.000048220158,0.035980225,-0.017715454,-0.007896423,0.018112183,0.037384033,0.0023212433,0.019958496,-0.018051147,-0.0079422,-0.014503479,0.005027771,-0.020217896,0.021697998,-0.0049438477,0.010971069,-0.019821167,0.016967773,0.03314209,-0.006450653,-0.0124053955,0.015289307,-0.0061035156,-0.012527466,0.023330688,0.0037651062,0.001329422,-0.01939392,-0.007209778,0.02432251,0.057891846,0.025894165,0.011604309,0.008239746,0.0045661926,-0.016830444,-0.0016860962,-0.0021419525,-0.028793335,-0.0287323,-0.011436462,-0.013885498,0.015266418,-0.0015802383,0.016281128,0.0068626404,0.02796936,-0.013175964,-0.014915466,-0.022094727,0.0395813,-0.0058135986,-0.013061523,-0.009757996,0.0075302124,0.011520386,-0.017913818,0.0016431808,-0.039093018,-0.04147339,-0.004562378,-0.018585205,0.028762817,0.011932373,-0.016204834,0.004573822,-0.014076233,0.0027675629,-0.01171875,0.019744873,-0.016860962,0.0034923553,0.013885498,0.019348145,-0.022018433,0.024490356,-0.011543274,-0.005466461,0.012107849,-0.012168884,0.00724411,-0.008407593,0.04034424,0.009490967,0.0030231476,0.03894043,-0.0014982224,0.0011730194,-0.032592773,0.014091492,-0.0045661926,-0.022460938,0.041534424,-0.021240234,-0.01789856,-0.008460999,-0.015571594,-0.018157959,0.017028809,0.018051147,0.023468018,-0.009925842,0.04815674,-0.016784668,0.0062294006,0.020355225,0.015541077,-0.0234375,0.003107071,0.028793335,0.008644104,-0.006412506,-0.007572174,-0.0057029724,-0.035095215,-0.0027503967,0.010231018,0.0033779144,-0.008110046,0.015487671,0.0005569458,0.033599854,-0.0015525818,0.0022792816,0.010566711,0.02041626,0.034820557,0.010620117,0.034332275,-0.01020813,-0.012382507,-0.0038528442,-0.00018620491,-0.017089844,-0.009994507,-0.0003297329,-0.0020103455,-0.027267456,0.010566711,-0.0058631897,0.032836914,-0.016525269,0.010902405,-0.02861023,-0.0019493103,-0.03982544,-0.011421204,-0.025497437,-0.0023651123,0.026931763,-0.005924225,0.026275635,-0.0013170242,-0.014915466,0.019973755,0.03387451,-0.002943039,-0.023864746,-0.013549805,0.0019311905,-0.0037899017,0.020935059,0.009979248,-0.023590088,-0.028121948,0.0049858093,-0.023651123,0.0072517395,0.0009870529,0.013404846,-0.0009074211,0.0059814453,-0.007797241,0.015380859,-0.0070495605,-0.015106201,-0.0002541542,0.00592041,0.034576416,0.02822876,0.0015916824,0.015609741,0.025421143,-0.032348633,0.06213379,0.00054216385,0.02684021,-0.024154663,0.0076522827,-0.03152466,-0.02986145,-0.010551453,0.003484726],"createdAt":"2026-04-21T18:32:21.731Z","updatedAt":"2026-04-22T13:32:22.760Z","lastSeenAt":"2026-04-22T13:32:22.760Z","tsv":"'/api/v1/inbox/22':69,177 '/request':19,38,168 '0.02':18,37,80,167 '000':84 '20':83 '402 payment API' '6':90 'Base network API' 'USDC pay-per-call' 'access':75,201 'account':102 'actual':241 'addit':232 'advertis':123 'ai':12,31,134 'analysi':138 'analyt':128 'api':5,24,45,74,100,192,200,222 'attach':109 'awar':238 'base':8,27,63,85 'base-network' 'behavior':242 'broad':50 'call':4,23,82 'caller':107,235 'catalog':51 'categori':126,193 'classif':141 'connect':227 'content':233 'convers':158 'cost':77 'crawl':217 'crypto API access' 'data':11,30,127,131 'decim':91 'descript':196 'detail':205 'doc':218 'document':191,214 'embed':142 'enabl':44 'endpoint':16,35,57,67,125,161,178,246 'estim':152 'exchang':147 'export':132 'feed':146 'financ':13,32,143 'four':124 'function':174 'gas':151 'generat':159 'geocod':156 'handl':94 'header':114 'howev':171 'inbox/22':184 'infrastructur':154 'insight':133 'key':101 'learn':136 'list':71,163 'lowpaymentfee' 'lowpaymentfee.com':39 'machin':135 'match':187 'metric':129 'micropayment API' 'network':64 'no-api-key' 'offer':10,29 'openapi':209 'page':219 'particular':245 'path':182 'pattern':183 'pay':2,21,54 'pay-per-cal':1,20 'pay-per-request':53 'payment':92,113,118 'per':3,22,55,81 'platform':6,25,46,122 'point':170 'post-endpoint' 'premium':73,199 'price':145,169,220 'prompt':229 'proof':119 'prospect':234 'protocol':98 'provid':48 'quot':150 'rate':148 'readm':221 'report':130 'request':56 'request/response':212 'requir':106 'return':224 'schema':213 'sentiment':137 'settl':58 'simpli':108,198 'spec':210 'specif':66,173 'subscript':104 'summar':140 'text':139 'token':149 'unclear':180 'undocu':248 'unit':86 'usdc':9,28,60,88 'usdc-settlement' 'util':15,34,155 'valid':117,157 'via':95 'wallet':228 'web3':144 'wider':121 'x':112 'x-payment':111 'x402':43,97 'x402 API' 'x402-enabled':42 'x402-payment'","prices":[{"id":"f06dece0-bddd-44fa-ae8e-00a19900b6b7","listingId":"47004673-5656-49d8-81f2-7bf716b182dd","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/inbox/22","description":"Premium API Access","outputSchema":{"input":{"type":"http","method":"GET","discoverable":true}},"maxAmountRequired":"20000","maxTimeoutSeconds":300}],"asset_contract":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","max_timeout_seconds":300},"createdAt":"2026-04-21T18:32:21.731Z"}],"sources":[{"listingId":"47004673-5656-49d8-81f2-7bf716b182dd","source":"x402_bazaar","sourceId":"https://lowpaymentfee.com/api/v1/inbox/22","sourceUrl":"https://api.cdp.coinbase.com/platform/v2/x402/discovery/resources","isPrimary":true,"firstSeenAt":"2026-04-21T18:32:21.731Z","lastSeenAt":"2026-04-22T13:32:22.760Z"}],"details":{"listingId":"47004673-5656-49d8-81f2-7bf716b182dd","quickStartSnippet":"# The endpoint requires an x402 X-PAYMENT header with a valid USDC payment proof on Base.\n# Without payment, it returns a 402 challenge:\ncurl -X POST https://lowpaymentfee.com/api/v1/inbox/22\n# Response: 402 with x402 challenge JSON describing payment requirements.\n# After constructing a valid payment, attach it:\ncurl -X POST https://lowpaymentfee.com/api/v1/inbox/22 \\\n  -H \"X-PAYMENT: <base64-encoded-payment-proof>\"","exampleRequest":null,"exampleResponse":{"error":"X-PAYMENT header is required","accepts":[{"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","extra":{"name":"USD Coin","version":"2"},"payTo":"0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3","scheme":"exact","network":"base","mimeType":"application/json","resource":"https://lowpaymentfee.com/api/v1/inbox/22","description":"Premium API Access","maxAmountRequired":"20000","maxTimeoutSeconds":300}],"x402Version":1},"schema":{"input":{"type":"http","method":"GET","discoverable":true}},"openapiUrl":null,"agentsTxtUrl":null,"citations":[{"claim":"The endpoint returns a valid x402 402 challenge with maxAmountRequired of 20000 USDC base units on Base network","source_url":"https://lowpaymentfee.com/api/v1/inbox/22"},{"claim":"The platform advertises endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categories all at $0.02/request","source_url":"https://lowpaymentfee.com"},{"claim":"The platform claims no API keys, no rate limits, instant access, and Base network settlement","source_url":"https://lowpaymentfee.com"},{"claim":"USDC contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","source_url":"https://lowpaymentfee.com/api/v1/inbox/22"}],"useCases":["Programmatic access to pay-per-call API services without account registration","Agent-driven API consumption where payment is settled on-chain per request","Testing x402 protocol integrations with a low-cost endpoint"],"bestFor":["Developers or agents wanting zero-signup, pay-as-you-go API access","x402 protocol experimentation on Base with USDC","Low-cost per-request API consumption without rate limits"],"notFor":["Users who need detailed API documentation or guaranteed SLAs before calling","High-volume batch workloads where per-request pricing may add up","Anyone who needs to understand the exact response schema before paying"],"kindDetails":{"x402_version":1,"resource_type":"http","bazaar_last_updated":"2026-02-17T23:13:08.493Z"},"updatedAt":"2026-04-22T13:32:22.760Z"}}