{"id":"416e6216-ce5c-455a-b754-69a3bbdd1df6","shortId":"sL93kp","kind":"x402","title":"Pay-per-call email API on Base via x402 — $0.02/request in USDC, no API keys required.","tagline":"Pay-per-call email API on Base via x402 — $0.02/request in USDC, no API keys required.","description":"lowpaymentfee.com hosts a collection of pay-per-request APIs accessible via the x402 payment protocol on the Base network. The specific endpoint `/api/v1/emails/42` is listed under \"Premium API Access\" and accepts POST requests, settling payments in USDC (contract 0x8335…2913 on Base). Each call costs up to 20,000 base units of USDC, which equals $0.02 (USDC uses 6 decimals). No API keys, subscriptions, or rate limits are advertised — callers simply attach an X-PAYMENT header with a valid x402 payment proof.\n\nThe broader platform offers endpoints spanning data & analytics (metrics, reports, data export, insights), AI & ML (sentiment analysis, text summarization, classification, embeddings), finance & Web3 (price feeds, exchange rates, token quotes, gas estimates), and infrastructure utilities (geocoding, validation, conversion, generation), all at the same $0.02/request price point. However, the probed endpoint path `/api/v1/emails/42` does not appear in the site's publicly listed API catalog, so its exact functionality is unclear — it may be an unlisted or legacy email-related resource.\n\nThe endpoint is live and returns a proper x402 402 challenge. Documentation beyond the landing page is extremely thin: the /docs, /api, /pricing, and /README pages all render only a \"Connect wallet\" prompt with no substantive content. There is no OpenAPI spec, no request/response schema documentation, and no usage examples available from the crawl.","tags":[],"capabilities":["x402-payment","usdc-settlement","base-network","pay-per-request","no-api-key","email-api","post-method"],"categories":["api","email"],"synonyms":["x402 email endpoint","pay-per-call API","USDC micropayment API","Base network API","lowpaymentfee","premium API access","crypto-paid email"],"warnings":["The endpoint path /api/v1/emails/42 does not appear in the provider's public API listing — its exact purpose is unknown.","All documentation pages (/docs, /api, /pricing, /README) returned only 'Connect wallet' with no substantive content.","No OpenAPI spec, request schema, or response schema is available — callers cannot know what to send or expect back.","The description 'Premium API Access' is generic and does not clarify what this endpoint does."],"endpointUrl":"https://lowpaymentfee.com/api/v1/emails/42","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/emails/42","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, but the specific resource (/api/v1/emails/42) is not listed on the site's catalog, there is no OpenAPI spec, no request/response schema, and all documentation pages are empty stubs. The exact functionality of this endpoint cannot be confirmed from available material.","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":"2026-04-21T19:09:04.932Z","embedding":[-0.016906738,-0.021133423,0.044830322,0.015930176,0.027313232,-0.045928955,-0.024658203,0.028381348,0.08123779,-0.06951904,0.028442383,-0.048339844,-0.029724121,-0.023757935,-0.043029785,0.008041382,0.0077056885,-0.031829834,-0.03149414,0.012145996,0.042144775,-0.02305603,-0.029510498,0.035186768,0.0014591217,-0.007801056,-0.025619507,-0.0011863708,0.0026931763,-0.048919678,0.035003662,-0.038909912,-0.02217102,0.012214661,-0.012031555,0.0084991455,-0.0051002502,0.04208374,0.031799316,0.005508423,0.0005850792,-0.04724121,0.018554688,-0.009399414,-0.061340332,0.006252289,0.0007328987,-0.019836426,0.018356323,0.0025157928,-0.015350342,0.004753113,-0.01247406,0.00248909,0.0052719116,0.021636963,-0.010124207,-0.0024795532,-0.0008568764,0.030258179,0.003583908,-0.058288574,-0.028778076,-0.016616821,0.0057411194,0.06222534,-0.009887695,0.035980225,0.015838623,0.08343506,0.026290894,0.053833008,0.044891357,0.004333496,-0.005115509,-0.024505615,-0.0015525818,0.043395996,-0.018493652,-0.033996582,-0.018356323,-0.006401062,-0.036865234,-0.0018987656,-0.03466797,-0.052368164,-0.009529114,0.025360107,-0.013092041,0.02772522,-0.10083008,-0.0021209717,0.0014505386,-0.007633209,0.011749268,-0.009521484,-0.01537323,0.013160706,0.0034275055,0.012687683,0.004753113,-0.04711914,0.011474609,0.00932312,0.03805542,0.045196533,0.027572632,0.022781372,0.022003174,-0.0028934479,-0.045166016,0.009300232,-0.012001038,-0.0049209595,0.009925842,0.0070228577,-0.0046577454,0.01361084,-0.039764404,0.010421753,-0.0368042,0.05227661,0.010269165,0.01625061,0.0047302246,-0.047912598,-0.02645874,0.003414154,-0.011238098,0.0062026978,0.033477783,0.023422241,0.04547119,-0.012130737,-0.036224365,0.015350342,-0.012886047,-0.016021729,-0.049713135,-0.024719238,0.06561279,-0.025024414,0.012046814,0.035705566,-0.09576416,-0.01537323,-0.040802002,-0.007701874,-0.007221222,-0.009780884,0.0076560974,0.006286621,-0.0017786026,-0.0063438416,-0.030776978,-0.017456055,0.0040740967,0.0362854,-0.010475159,0.033996582,-0.0020103455,0.015731812,0.02696228,-0.001791954,0.010108948,0.023239136,0.008323669,-0.06976318,-0.074035645,-0.023376465,-0.0029182434,-0.002696991,-0.03527832,0.030059814,-0.0056610107,-0.059448242,0.00074243546,-0.0059280396,-0.013877869,-0.041778564,-0.002658844,-0.023010254,0.0031719208,-0.00166893,-0.06842041,-0.026367188,-0.010047913,0.06124878,0.025238037,0.023208618,0.040039062,-0.029830933,0.037628174,0.03475952,-0.027542114,-0.027069092,0.024658203,-0.023727417,0.0021953583,0.022735596,0.008544922,-0.03164673,0.043670654,0.068603516,0.015266418,-0.01789856,0.0016183853,-0.05618286,-0.043121338,-0.013000488,0.024673462,-0.002161026,-0.0096206665,0.02432251,-0.03668213,-0.031204224,0.0021705627,0.009429932,0.010444641,0.06524658,0.0037288666,-0.0023612976,0.024536133,0.025039673,-0.04119873,0.03765869,0.044799805,0.014282227,-0.02305603,-0.019363403,0.0287323,0.033691406,-0.0104904175,0.018417358,-0.013259888,0.019104004,-0.016433716,-0.003791809,0.02078247,-0.007549286,-0.027130127,-0.021133423,-0.023086548,0.027496338,0.00466156,-0.023727417,-0.03378296,-0.06335449,0.054656982,0.031341553,0.038757324,0.0017986298,0.013206482,-0.0340271,-0.018096924,-0.07330322,0.055786133,0.06304932,-0.0065193176,-0.019424438,0.033416748,-0.019622803,-0.02355957,0.017623901,-0.0005893707,-0.0309906,-0.021072388,0.0033359528,-0.041870117,-0.00349617,0.018814087,0.04522705,0.05218506,-0.0018625259,-0.03942871,-0.0077934265,-0.0067481995,-0.0047798157,-0.01637268,-0.0036392212,-0.0065841675,0.014984131,0.013450623,-0.029174805,0.021743774,-0.0063323975,-0.0018167496,0.000011742115,0.013748169,-0.02722168,-0.02571106,0.013587952,0.008262634,-0.05053711,-0.015411377,0.00060606,0.059143066,-0.046020508,0.033935547,-0.008308411,0.0015687943,0.05456543,0.000103354454,-0.049468994,-0.011909485,0.023117065,0.014045715,0.05908203,0.013679504,-0.010948181,-0.016403198,0.076538086,-0.018615723,-0.013252258,0.014511108,0.029800415,0.022140503,0.011054993,-0.06652832,-0.047821045,-0.008605957,-0.012207031,0.023208618,-0.03540039,0.025558472,0.0069770813,0.0184021,-0.024291992,0.000050485134,-0.03366089,0.007751465,-0.031066895,-0.00006687641,-0.0231781,-0.0018444061,0.016143799,0.008811951,-0.0058135986,0.0049438477,0.041381836,0.002866745,0.0014238358,-0.022827148,-0.03768921,-0.030731201,-0.016586304,-0.0036525726,0.023712158,0.021820068,0.0413208,-0.053466797,0.02444458,0.03277588,0.02420044,0.023132324,-0.002325058,0.02104187,-0.08026123,-0.032684326,-0.025726318,-0.016708374,0.036071777,0.03111267,-0.0075569153,0.06378174,0.009635925,-0.026245117,-0.064086914,0.031677246,-0.03286743,0.0054740906,0.066833496,-0.015045166,-0.01802063,0.007160187,-0.024032593,0.006996155,0.03942871,0.019699097,0.030639648,0.06762695,0.048217773,-0.010910034,-0.0008482933,0.019561768,0.015548706,0.00434494,-0.01676941,-0.032409668,-0.018600464,0.03866577,-0.0135650635,-0.020233154,-0.06222534,0.07299805,0.05633545,0.07861328,0.029403687,0.01386261,0.03338623,-0.018737793,0.018600464,-0.009490967,-0.026901245,-0.018707275,-0.05206299,0.028335571,-0.009689331,0.008926392,-0.029937744,0.023330688,-0.004085541,0.017852783,-0.016662598,0.055725098,-0.013839722,-0.0027637482,0.026473999,0.023223877,0.03930664,0.04336548,-0.04989624,0.03414917,0.020767212,-0.040496826,-0.0005903244,0.023620605,-0.02230835,-0.0059013367,-0.060516357,-0.041381836,-0.017669678,-0.027694702,-0.046173096,-0.0023097992,-0.0000039339066,0.012145996,0.046081543,-0.008872986,-0.019180298,0.0008864403,-0.012680054,-0.06512451,-0.0072288513,-0.03842163,0.004722595,0.03845215,-0.031066895,0.0004105568,-0.005542755,-0.010673523,-0.005886078,0.024414062,0.015571594,-0.004055023,-0.029388428,0.018753052,0.0011091232,-0.0029678345,0.0034103394,0.03189087,0.014640808,0.040252686,0.021377563,-0.0015068054,-0.018585205,-0.052947998,0.036132812,-0.04736328,0.017715454,0.04812622,-0.02470398,-0.0071029663,-0.018051147,-0.03414917,-0.0335083,0.0131073,-0.04840088,-0.013824463,0.022872925,-0.012359619,-0.01789856,-0.039489746,-0.018600464,-0.022232056,0.04840088,0.01600647,-0.000177145,-0.05203247,-0.0015029907,-0.0015363693,0.0023117065,0.017654419,-0.014732361,-0.0062217712,-0.012428284,-0.023162842,-0.010383606,0.00051164627,0.027282715,-0.023330688,-0.018463135,0.00497818,0.0020542145,0.046875,0.027496338,0.018081665,0.035186768,-0.026565552,-0.0059814453,0.0014772415,0.041748047,0.0059928894,-0.008796692,-0.041870117,0.028366089,0.008598328,0.05001831,-0.03173828,-0.020874023,-0.01008606,0.020645142,0.003791809,0.0015354156,0.0017194748,-0.015403748,-0.051239014,-0.0713501,0.02998352,-0.018432617,0.023376465,0.010437012,0.01184082,0.015411377,-0.0039901733,-0.0049095154,0.02130127,-0.032470703,-0.023254395,-0.02217102,-0.026473999,-0.009544373,-0.014076233,-0.023590088,0.02709961,-0.014808655,0.028198242,0.016342163,-0.01600647,0.02255249,-0.0024166107,-0.00025558472,0.023132324,-0.012161255,0.0075302124,0.03338623,0.007911682,-0.03717041,0.023529053,0.0051460266,0.019805908,-0.0034599304,0.039123535,0.047027588,0.007385254,0.001739502,-0.0011701584,-0.015151978,-0.02520752,0.01763916,0.009002686,0.006099701,-0.021591187,-0.044433594,0.011497498,0.012901306,-0.036193848,-0.02482605,0.0022659302,0.021011353,-0.037597656,0.01727295,0.021514893,0.047607422,-0.022598267,0.0027675629,0.009361267,0.034240723,0.037475586,0.019546509,0.006286621,0.018112183,0.000895977,-0.0061073303,-0.0005235672,-0.017059326,0.020355225,-0.0042800903,0.013572693,0.018249512,0.0014886856,-0.013015747,-0.032165527,-0.0119018555,-0.000487566,-0.03125,0.020462036,0.030593872,0.03753662,-0.03793335,0.018081665,0.014877319,-0.0152282715,-0.0034103394,0.0030117035,0.03793335,0.0005745888,-0.021697998,0.016235352,0.02458191,0.03488159,-0.06185913,-0.018798828,-0.00045633316,0.014389038,-0.036254883,-0.027832031,-0.04763794,-0.0068206787,0.037231445,0.01701355,0.02305603,0.035583496,-0.008323669,0.00642395,0.020874023,0.009666443,-0.019760132,0.0044136047,-0.03665161,-0.016082764,-0.007030487,0.0107803345,-0.029205322,0.002286911,-0.009986877,-0.037902832,0.008377075,-0.013496399,0.0015907288,-0.010292053,0.010696411,0.041900635,0.003578186,0.01965332,-0.028457642,-0.032287598,-0.0045394897,0.008399963,0.010688782,-0.058135986,0.0074310303,-0.015426636,-0.0093307495,0.005695343,-0.00077962875,0.029067993,0.017654419,-0.002105713,0.029830933,-0.061065674,0.047058105,-0.024368286,0.005584717,-0.006668091,-0.024963379,-0.017822266,-0.014465332,-0.011932373,0.051849365,-0.040863037,-0.026184082,-0.033569336,-0.05218506,-0.017486572,-0.060302734,0.008094788,0.026107788,0.027786255,-0.025436401,0.006214142,0.0069732666,0.0046157837,-0.023422241,-0.00064611435,-0.009857178,0.020446777,0.021514893,0.01386261,-0.041015625,-0.028152466,-0.010025024,-0.0048065186,-0.013931274,-0.045654297,-0.018005371,-0.0069389343,-0.0016717911,-0.014076233,-0.014770508,-0.030014038,-0.004589081,-0.044403076,0.02709961,-0.006275177,0.006767273,-0.0013475418,-0.03704834,-0.010932922,0.011352539,-0.013969421,0.027038574,0.001004219,-0.0044021606,-0.028045654,0.009963989,0.01625061,0.019424438,-0.01398468,-0.018035889,0.00040841103,-0.015007019,-0.050933838,-0.002445221,-0.0047912598,0.00009149313,-0.012130737,0.005012512,-0.054626465,0.006374359,-0.01777649,0.00011140108,0.032043457,0.015777588,0.008171082,0.0019483566,0.019989014,-0.0033073425,-0.014228821,-0.0385437,0.026901245,0.010910034,-0.006542206,0.041137695,0.033843994,-0.0029411316,-0.02949524,0.020095825,0.005218506,0.0039901733,-0.005027771,0.018157959,-0.02204895,0.009994507,0.005268097,-0.026031494,-0.034423828,-0.009094238,0.08648682,0.0059661865,-0.015960693,-0.0015306473,-0.0234375,0.0098724365,0.029571533,-0.02796936,0.0033912659,-0.023422241,0.018844604,-0.031707764,0.016723633,-0.008216858,0.022857666,-0.01763916,-0.05126953,-0.021347046,-0.020355225,-0.007835388,-0.05923462,-0.03656006,-0.054992676,0.015548706,-0.012466431,-0.014221191,0.0003490448,0.006259918,-0.016403198,-0.07385254,0.00061798096,0.043792725,0.0034656525,0.03125,-0.022476196,0.008338928,0.015960693,-0.028381348,0.007575989,0.026382446,-0.035064697,-0.0049743652,-0.029907227,0.022903442,-0.014373779,-0.013298035,0.0132369995,0.0024318695,0.022323608,-0.014389038,0.017654419,-0.014732361,-0.0005097389,-0.027420044,0.008674622,-0.01158905,0.0071868896,0.030090332,-0.03652954,0.019363403,-0.0058021545,-0.0077667236,0.0028476715,0.021011353,0.04800415,-0.027389526,-0.014228821,0.0069007874,0.0008196831,0.05102539,-0.02760315,0.040252686,0.00819397,-0.027435303,0.01977539,0.0015907288,-0.025939941,-0.032592773,-0.013427734,0.031311035,0.0050621033,0.009147644,-0.010467529,0.0052261353,0.0031337738,0.00019907951,0.011749268,0.0023117065,-0.027862549,-0.030639648,-0.009300232,0.010147095,0.011108398,-0.0030460358,0.024627686,0.025238037,0.036346436,-0.007209778,-0.01828003,-0.002527237,0.031951904,-0.00045466423,-0.00844574,0.029693604,-0.0004911423,-0.0013847351,0.018753052,0.001791954,-0.03817749,-0.018157959,-0.032562256,-0.034423828,-0.010925293,-0.0002770424,0.004508972,-0.007881165,0.0073928833,-0.0046424866,-0.02418518,0.0019025803,-0.034820557,-0.0154418945,-0.0011301041,-0.0037345886,0.028076172,-0.00504303,0.013641357,0.010696411,0.0021476746,0.028121948,0.01096344,-0.008514404,0.036102295,0.036193848,0.0077056885,-0.023254395,-0.015716553,-0.011245728,-0.0007162094,-0.005531311,-0.03616333,0.0084991455,0.056518555,-0.017913818,0.0087890625,0.0104522705,0.020477295,-0.017425537,0.0013332367,-0.012046814,0.023971558,-0.0020065308,0.022705078,-0.04345703,0.030258179,0.0152282715,0.001739502,-0.0067100525,-0.009170532,-0.032592773,0.009437561,0.0049362183,-0.007926941,0.047058105,0.0024490356,0.0317688,-0.016403198,-0.01902771,0.015640259,-0.026565552,-0.031204224,0.032196045,0.0039711,-0.00087070465,0.010726929,-0.020980835,0.05142212,-0.023605347,0.018951416,-0.0020160675,-0.0047721863,-0.0053749084,-0.020874023,0.0038604736,-0.027832031,-0.023422241,0.00027608871,-0.014480591,0.056915283,0.013626099,0.038970947,0.052001953,0.013366699,-0.016601562,-0.04724121,-0.05014038,0.014038086,-0.006958008,0.019699097,-0.015365601,0.053894043,0.032684326,0.013145447,0.03363037,0.030303955,0.03515625,0.00020039082,0.002035141,-0.023757935,0.007888794,-0.0057868958,0.014312744,-0.0024528503,0.03515625,-0.044677734,0.018585205,0.0129470825,0.026657104,-0.02684021,0.03665161,0.0637207,0.009155273,-0.010345459,0.03363037,-0.0007071495,-0.023529053,-0.006351471,-0.015991211,0.048675537,0.01096344,0.039489746,0.064453125,0.010009766,-0.002696991,0.012451172,-0.039611816,-0.017181396,0.05444336,0.030532837,-0.012184143,-0.011604309,-0.0043029785,0.01197052,-0.051849365,-0.027862549,0.017593384,0.00056409836,0.009796143,-0.0014343262,-0.012680054,-0.014404297,0.02116394,0.015625,0.005695343,0.00015437603,0.016235352,0.031799316,-0.0038471222,0.04309082,-0.011520386,0.016906738,-0.026504517,-0.030517578,0.017303467,-0.0004312992,-0.013473511,-0.027130127,0.022659302,0.015991211,0.0362854,0.050201416,-0.015098572,0.008956909,0.02809143,0.016311646,0.010276794,0.0552063,0.02848816,0.000075638294,0.042541504,0.027542114,0.028747559,-0.022232056,0.020019531,0.015258789,0.0018119812,0.005958557,-0.006664276,0.0016269684,-0.020446777,0.019241333,-0.008460999,-0.01586914,0.014129639,0.028915405,-0.0019874573,0.00415802,0.010543823,0.002910614,-0.01436615,0.00258255,0.0054779053,-0.013877869,0.042633057,0.017959595,0.033813477,-0.005619049,0.024658203,-0.0076828003,-0.01637268,-0.017623901,0.019943237,-0.043304443,0.009864807,-0.008613586,-0.01360321,-0.042144775,0.014045715,0.018692017,-0.017608643,0.04421997,0.01550293,-0.010955811,0.004348755,0.025222778,0.008544922,0.0055503845,0.0021953583,-0.027359009,0.032043457,0.051483154,0.012939453,-0.003692627,-0.0368042,0.0005540848,0.0075035095,-0.006893158,-0.0050468445,-0.012451172,-0.017791748,-0.030166626,0.027511597,0.022003174,0.011924744,0.047790527,-0.011909485,-0.021072388,0.013809204,0.027420044,-0.003320694,-0.0022945404,-0.005722046,0.018463135,-0.014930725,0.045532227,0.036346436,0.017105103,0.027786255,-0.0013694763,-0.015655518,0.008026123,0.00008422136,0.0132751465,-0.018234253,0.0039253235,-0.007019043,0.032440186,-0.016082764,-0.02293396,-0.002090454,-0.011230469,-0.03189087,-0.016418457,0.016601562,0.014022827,0.03753662,0.035308838,0.02267456,-0.034179688,0.061187744,-0.029144287,0.03665161,-0.0054855347,-0.014320374,0.057495117,0.028015137,0.029937744,0.0060920715,0.021453857,-0.040374756,0.005680084,0.043884277,0.020477295,0.01776123,-0.0039596558,-0.032684326,0.03552246,-0.0013875961,0.023880005,-0.027694702,-0.0005750656,0.013801575,-0.0010795593,-0.022109985,-0.00041365623,-0.0062294006,-0.0084991455,0.03817749,-0.033569336,-0.035583496,-0.019042969,-0.0124435425,0.027435303,-0.022735596,-0.0039367676,0.0022392273,-0.01737976,0.0016031265,-0.003156662,-0.026321411,0.006755829,0.03439331,-0.03930664,-0.010101318,-0.002702713,0.021530151,-0.021743774,0.03479004,0.02798462,-0.0076408386,0.006000519,0.04257202,-0.0056037903,0.0262146,-0.024246216,0.025634766,0.041015625,0.0060195923,-0.015701294,0.004776001,0.010856628,-0.011856079,0.017089844,0.026565552,-0.0126953125,0.007083893,0.0023860931,-0.008354187,0.0007200241,0.008590698,-0.012207031,0.013305664,-0.014808655,-0.022537231,-0.0027389526,0.00566864,-0.0063972473,0.0034236908,-0.0040893555,-0.0073509216,0.009841919,0.035247803,0.023803711,-0.034698486,-0.009719849,0.0006170273,0.00021123886,-0.024734497,-0.010108948,0.008934021,-0.045562744,0.0135650635,0.020248413,0.009666443,0.008605957,-0.021347046,0.013046265,0.023025513,0.021606445,0.013748169,-0.005924225,-0.00058555603,0.010856628,-0.002565384,-0.01171875,-0.0073051453,-0.015731812,0.004928589,0.02671814,-0.012527466,-0.033477783,0.027130127,-0.005874634,0.0037784576,0.0020751953,-0.0074043274,0.02796936,0.006866455,0.002658844,-0.0051727295,0.011604309,-0.015548706,-0.02255249,-0.015220642,0.022705078,0.06414795,-0.017028809,-0.014312744,0.024291992,0.019729614,0.0151901245,0.030670166,-0.016998291,0.047790527,0.013755798,-0.013000488,-0.026519775,0.011436462,-0.021560669,-0.018844604,0.014549255,-0.029754639,-0.019821167,0.0066833496,0.0030117035,-0.0039863586,-0.027145386,-0.0007920265,-0.012573242,-0.027328491,0.029754639,-0.0031433105,0.00047564507,-0.030929565,-0.001493454,-0.000487566,-0.028152466,-0.044952393,-0.0061569214,-0.0026168823,-0.01360321,-0.063964844,0.014984131,-0.03378296,0.00957489,-0.015655518,0.0017709732,-0.009765625,0.029541016,-0.0076828003,0.0012273788,-0.0029239655,0.01638794,0.03866577,-0.002872467,0.040130615,-0.043182373,-0.041412354,-0.026687622,-0.0035915375,-0.013252258,0.022827148,0.00868988,0.023239136,0.018035889,-0.0066223145,0.002128601,-0.0050239563,-0.014877319,-0.015808105,-0.025253296,-0.033050537,0.024780273,0.013061523,-0.012184143,-0.001168251,0.031921387,-0.015533447,-0.019866943,0.01927185,0.037597656,0.005519867,0.022201538,-0.009613037,-0.008308411,-0.008453369,-0.00009423494,-0.023620605,0.01576233,-0.0009784698,0.0062065125,-0.015174866,0.016906738,0.024475098,-0.011177063,0.010253906,0.025222778,0.008079529,-0.009567261,0.021728516,0.0104904175,0.009033203,-0.008728027,-0.0016851425,0.017562866,0.0423584,0.014274597,0.017715454,-0.0057868958,0.0003976822,-0.0061950684,-0.0048828125,0.0018920898,-0.012527466,-0.036865234,-0.016525269,-0.03692627,0.005050659,-0.00022113323,0.010673523,-0.0118255615,0.029464722,-0.0039901733,-0.03866577,-0.015060425,0.02331543,0.01574707,-0.00674057,-0.008140564,0.015426636,-0.006450653,-0.036071777,0.01184845,-0.060516357,-0.051361084,0.008575439,-0.01966858,0.017120361,0.0071029663,-0.011116028,0.004108429,-0.007926941,-0.0069503784,-0.0051002502,0.02330017,-0.000011205673,-0.0022220612,0.017562866,0.018692017,-0.014083862,0.02230835,-0.011039734,-0.0011196136,0.014259338,-0.020858765,0.018066406,-0.0047416687,0.020553589,-0.018981934,-0.0053367615,0.014389038,-0.010673523,-0.0038795471,-0.0524292,0.0077209473,0.006755829,-0.013946533,0.018844604,-0.02619934,-0.03125,-0.013824463,-0.016555786,-0.020751953,0.012931824,0.028305054,0.03704834,0.007511139,0.04675293,-0.029067993,-0.0032596588,0.017028809,0.00548172,-0.020996094,-0.006462097,0.022598267,0.0004518032,-0.015075684,-0.0155181885,-0.0061187744,-0.0345459,-0.019699097,0.01864624,-0.004840851,-0.0121154785,0.032104492,0.012641907,0.04458618,0.00035429,0.009864807,0.0074501038,0.0013427734,0.020950317,-0.007633209,0.049713135,-0.0040512085,-0.026016235,0.00083494186,0.0047416687,-0.015136719,-0.01576233,-0.00016582012,-0.0039749146,-0.038360596,0.010795593,-0.010276794,0.032806396,-0.024490356,0.024291992,-0.030166626,-0.0051612854,-0.033721924,-0.0061416626,-0.0335083,0.002658844,0.04083252,0.009689331,0.014129639,-0.014167786,-0.02659607,0.01285553,0.017852783,0.0010204315,-0.03363037,-0.02760315,0.0048332214,0.0012741089,0.014007568,0.012336731,-0.022720337,-0.008987427,0.009300232,-0.004196167,0.0063095093,-0.00054597855,0.0033302307,-0.0031795502,-0.0024337769,0.008171082,0.02571106,-0.0038414001,-0.014549255,-0.0053138733,-0.0039100647,0.031677246,0.037139893,-0.011459351,0.01939392,0.019592285,-0.03933716,0.053588867,-0.012435913,0.016433716,-0.016418457,0.0042533875,-0.033477783,-0.025024414,-0.01158905,-0.013954163],"createdAt":"2026-04-21T18:32:11.233Z","updatedAt":"2026-04-22T01:02:03.569Z","lastSeenAt":"2026-04-22T01:02:03.569Z","tsv":"'/api':222 '/api/v1/emails/42':60,172 '/docs':221 '/pricing':223 '/readme':225 '/request':12,30,164 '0.02':11,29,93,163 '000':86 '0x8335':76 '20':85 '2913':77 '402':210 '6':96 'Base network API' 'USDC micropayment API' 'accept':68 'access':47,66 'advertis':106 'ai':134 'analysi':137 'analyt':128 'api':6,16,24,34,46,65,99,182 'appear':175 'attach':109 'avail':251 'base':8,26,55,79,87 'base-network' 'beyond':213 'broader':122 'call':4,22,81 'caller':107 'catalog':183 'challeng':211 'classif':140 'collect':40 'connect':231 'content':237 'contract':75 'convers':157 'cost':82 'crawl':254 'crypto-paid email' 'data':127,131 'decim':97 'document':212,246 'email':5,23,198 'email-api' 'email-rel':197 'embed':141 'endpoint':59,125,170,202 'equal':92 'estim':151 'exact':186 'exampl':250 'exchang':146 'export':132 'extrem':218 'feed':145 'financ':142 'function':187 'gas':150 'generat':158 'geocod':155 'header':114 'host':38 'howev':167 'infrastructur':153 'insight':133 'key':17,35,100 'land':215 'legaci':196 'limit':104 'list':62,181 'live':204 'lowpaymentfee' 'lowpaymentfee.com':37 'may':191 'metric':129 'ml':135 'network':56 'no-api-key' 'offer':124 'openapi':241 'page':216,226 'path':171 'pay':2,20,43 'pay-per-cal':1,19 'pay-per-call API' 'pay-per-request':42 'payment':51,72,113,119 'per':3,21,44 'platform':123 'point':166 'post':69 'post-method' 'premium':64 'premium API access' 'price':144,165 'probe':169 'prompt':233 'proof':120 'proper':208 'protocol':52 'public':180 'quot':149 'rate':103,147 'relat':199 'render':228 'report':130 'request':45,70 'request/response':244 'requir':18,36 'resourc':200 'return':206 'schema':245 'sentiment':136 'settl':71 'simpli':108 'site':178 'span':126 'spec':242 'specif':58 'subscript':101 'substant':236 'summar':139 'text':138 'thin':219 'token':148 'unclear':189 'unit':88 'unlist':194 'usag':249 'usdc':14,32,74,90,94 'usdc-settlement' 'use':95 'util':154 'valid':117,156 'via':9,27,48 'wallet':232 'web3':143 'x':112 'x-payment':111 'x402':10,28,50,118,209 'x402 email endpoint' 'x402-payment'","prices":[{"id":"a15c796d-acd1-4e98-a6b6-5ac77cbc647c","listingId":"416e6216-ce5c-455a-b754-69a3bbdd1df6","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/emails/42","description":"Premium API Access","outputSchema":{"input":{"type":"http","method":"GET","discoverable":true}},"maxAmountRequired":"20000","maxTimeoutSeconds":300}],"asset_contract":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","max_timeout_seconds":300},"createdAt":"2026-04-21T18:32:11.233Z"}],"sources":[{"listingId":"416e6216-ce5c-455a-b754-69a3bbdd1df6","source":"x402_bazaar","sourceId":"https://lowpaymentfee.com/api/v1/emails/42","sourceUrl":"https://api.cdp.coinbase.com/platform/v2/x402/discovery/resources","isPrimary":true,"firstSeenAt":"2026-04-21T18:32:11.233Z","lastSeenAt":"2026-04-22T01:02:03.569Z"}],"details":{"listingId":"416e6216-ce5c-455a-b754-69a3bbdd1df6","quickStartSnippet":"curl -X POST https://lowpaymentfee.com/api/v1/emails/42 \\\n  -H \"Content-Type: application/json\" \\\n  -H \"X-PAYMENT: <x402-payment-proof>\"","exampleRequest":null,"exampleResponse":null,"schema":{"input":{"type":"http","method":"GET","discoverable":true}},"openapiUrl":null,"agentsTxtUrl":null,"citations":[{"claim":"The site lists APIs at $0.02/request with no API keys, no rate limits, and instant access on the Base network.","source_url":"https://lowpaymentfee.com"},{"claim":"The x402 challenge specifies maxAmountRequired of 20000 base units of USDC (0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Base, equaling $0.02.","source_url":"https://lowpaymentfee.com/api/v1/emails/42"},{"claim":"The endpoint /api/v1/emails/42 is not listed among the publicly advertised APIs on the landing page.","source_url":"https://lowpaymentfee.com"}],"useCases":["Programmatic email data retrieval or operations paid per-call with USDC","Agent-driven workflows needing keyless, pay-as-you-go API access","Integrating x402-compatible payment flows into automated pipelines"],"bestFor":["Developers wanting zero-signup, pay-per-use API access","AI agents with x402 payment capability on Base","Users who prefer crypto micropayments over subscription billing"],"notFor":["Users needing detailed API documentation or OpenAPI specs before integrating","High-volume callers who would benefit from bulk pricing or subscriptions","Anyone without a Base-network USDC wallet or x402 client"],"kindDetails":{"x402_version":1,"resource_type":"http","bazaar_last_updated":"2026-02-17T23:13:21.126Z"},"updatedAt":"2026-04-22T01:02:03.569Z"}}