{"id":"ca2d9b1a-f4e2-4eae-ad92-ea5b4365bf8a","shortId":"zcCWT3","kind":"x402","title":"x402-gated email data endpoint on Base, pay $0.02 per request in USDC.","tagline":"x402-gated email data endpoint on Base, pay $0.02 per request in USDC.","description":"This endpoint at lowpaymentfee.com provides premium API access to an email-related resource (specifically `/api/v1/emails/63`) gated by the x402 payment protocol. The endpoint accepts POST requests and returns JSON. Payment is settled on the Base network using USDC (contract 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) at a cost of $0.02 per request (20,000 base units with 6 decimals). No API keys or rate limits are required — callers simply attach an X-PAYMENT header with a valid x402 payment proof.\n\nThe provider, lowpaymentfee.com, hosts a broader catalog of x402-gated APIs spanning data & analytics, AI/ML inference (sentiment analysis, 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 $0.02 per request. However, the specific endpoint being listed here (`/api/v1/emails/63`) is not described on the provider's landing page among the advertised categories, and its exact functionality (e.g., whether it retrieves a specific email record, performs email validation, or something else) is unclear from available documentation.\n\nDocumentation is extremely sparse — the docs, API, pricing, and README pages all render only a \"Connect wallet\" prompt with no substantive content. There is no OpenAPI schema, no request/response examples, and no description of what the emails endpoint actually returns. Callers should be aware that the endpoint's behavior must be discovered empirically.","tags":[],"capabilities":["x402-payment","usdc-base","per-request-billing","json-response","post-method","no-api-key","email-data"],"categories":["data","email"],"synonyms":["email API","x402 email endpoint","pay-per-request email","USDC API","Base network API","lowpaymentfee","402 payment email"],"warnings":["The /api/v1/emails/63 endpoint is not listed among the provider's advertised API catalog — its purpose is unclear.","All documentation pages (docs, API, pricing, README) render only 'Connect wallet' with no substantive content.","No OpenAPI schema, request body schema, or response examples are available.","The exact nature of the data returned (email content, metadata, validation result, etc.) cannot be determined from available sources."],"endpointUrl":"https://lowpaymentfee.com/api/v1/emails/63","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/63","description":"Premium API Access","outputSchema":{"input":{"type":"http","method":"GET","discoverable":true}},"maxAmountRequired":"20000","maxTimeoutSeconds":300}]},"qualityScore":"0.250","qualityRationale":"The endpoint is live (returns a valid 402 x402 challenge), but there is no documentation, no OpenAPI schema, no request/response examples, and the specific emails/63 endpoint is not even listed among the provider's advertised APIs. The endpoint's actual functionality is unknown.","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":"2026-04-21T19:20:43.026Z","embedding":[-0.01991272,-0.0060768127,0.061157227,0.020385742,0.03387451,-0.04458618,-0.025970459,0.021469116,0.07067871,-0.07543945,0.032043457,-0.034576416,-0.054229736,-0.024551392,-0.03955078,0.0048294067,0.007331848,-0.019165039,-0.040740967,0.022644043,0.04196167,-0.011001587,-0.011116028,0.028549194,-0.0068206787,0.004634857,-0.013587952,-0.00028157234,0.006729126,-0.042022705,0.010391235,-0.031036377,-0.00111866,0.005558014,-0.013290405,0.031173706,-0.010513306,0.050628662,0.029815674,0.00038933754,0.0043296814,-0.034332275,0.007331848,0.0024852753,-0.0231781,-0.008522034,0.014251709,-0.032806396,0.00504303,-0.011817932,-0.020996094,-0.003025055,-0.0146865845,0.010673523,0.026000977,0.030761719,-0.0016126633,-0.018218994,0.012512207,0.033172607,-0.0017976761,-0.07458496,-0.030395508,-0.017349243,0.011016846,0.052642822,-0.016479492,0.03842163,0.013130188,0.09729004,0.022064209,0.049804688,0.05834961,0.0002412796,-0.00023519993,-0.034118652,0.005924225,0.019042969,-0.029586792,-0.031982422,-0.017059326,-0.013549805,-0.046966553,-0.0063209534,-0.020477295,-0.068603516,-0.0047683716,0.024246216,-0.019424438,0.02709961,-0.11053467,-0.015159607,-0.011428833,0.01953125,0.0013818741,0.0031986237,-0.0055007935,-0.007156372,0.008506775,-0.00012683868,0.013336182,-0.03643799,0.026168823,0.011238098,0.05404663,0.01663208,0.014640808,0.014381409,0.02166748,-0.009338379,-0.018035889,-0.0025043488,-0.03274536,-0.00674057,0.006500244,-0.005710602,-0.015510559,0.01838684,-0.023910522,0.02784729,-0.04244995,0.04812622,0.0053977966,0.0038471222,0.004386902,-0.04711914,-0.030593872,-0.014015198,-0.003370285,0.0076560974,0.05105591,0.0085372925,0.04660034,-0.026443481,-0.03967285,0.021774292,-0.00806427,-0.018630981,-0.057769775,-0.01374054,0.047180176,-0.022247314,0.007385254,0.028503418,-0.07739258,-0.00982666,-0.04107666,0.006515503,-0.013717651,0.00004643202,0.009590149,0.01626587,0.0010280609,-0.011955261,-0.031021118,-0.006580353,0.00059986115,0.047821045,-0.0026130676,0.021408081,-0.016036987,0.023880005,0.046539307,-0.0072135925,0.0008049011,0.03970337,-0.007129669,-0.07861328,-0.05960083,-0.02859497,-0.011833191,-0.0053215027,-0.03778076,0.024154663,-0.00856781,-0.055999756,-0.01259613,-0.001876831,0.009185791,-0.033050537,-0.011070251,-0.02784729,-0.0154953,0.0025806427,-0.066101074,-0.012283325,-0.013999939,0.06951904,0.0059814453,0.009056091,0.029663086,-0.010688782,0.041656494,0.043640137,-0.030258179,-0.019226074,0.021499634,-0.02255249,0.019058228,0.034820557,0.02230835,-0.033172607,0.03515625,0.047546387,-0.0079193115,-0.021713257,0.026031494,-0.04623413,-0.01777649,-0.011260986,0.027359009,-0.008613586,-0.028884888,0.011779785,-0.028778076,-0.027114868,-0.007091522,-0.014533997,0.021606445,0.06628418,0.0069274902,0.014961243,0.012077332,0.02368164,-0.04058838,0.028656006,0.04623413,0.016357422,-0.028503418,-0.027999878,0.02709961,0.043762207,-0.014076233,0.01121521,-0.012374878,-0.00002360344,-0.029800415,-0.012939453,0.03744507,0.007369995,-0.03656006,-0.031829834,-0.00066280365,0.027450562,-0.0025520325,-0.03302002,-0.043151855,-0.048980713,0.05734253,0.054718018,0.009780884,0.006767273,0.0079422,-0.043304443,-0.017944336,-0.07354736,0.045196533,0.0637207,-0.013725281,-0.03253174,0.047973633,-0.008872986,-0.019927979,0.0036296844,0.009735107,-0.026779175,-0.02204895,-0.0024814606,-0.054901123,0.023590088,0.012008667,0.041107178,0.053863525,-0.0038280487,-0.0390625,0.0058174133,0.009162903,-0.010734558,-0.022659302,-0.008598328,-0.0061569214,0.010017395,0.032348633,-0.03338623,0.015960693,-0.0006580353,0.019958496,-0.003932953,0.0004374981,-0.03463745,-0.008636475,0.014945984,0.009437561,-0.049987793,0.006340027,0.0035495758,0.057403564,-0.04260254,0.0413208,-0.009536743,-0.0022449493,0.054382324,-0.01398468,-0.040771484,-0.032989502,0.020080566,0.031677246,0.058288574,0.016967773,0.027297974,-0.014884949,0.05026245,-0.0022602081,0.008491516,-0.006839752,0.046295166,0.016586304,0.03527832,-0.060058594,-0.05657959,-0.012123108,-0.0101623535,0.023620605,-0.04598999,0.020202637,0.011802673,0.013496399,-0.020523071,-0.005886078,-0.036743164,0.006702423,-0.02571106,0.0016393661,-0.031311035,-0.0037593842,0.02607727,0.020080566,0.0062065125,-0.004047394,0.035095215,-0.005455017,-0.010910034,-0.022491455,-0.03640747,-0.04058838,-0.01939392,-0.007911682,0.028152466,0.018920898,0.023101807,-0.051818848,0.030258179,0.033966064,0.012435913,0.025344849,-0.008354187,0.02911377,-0.07696533,-0.023147583,-0.014480591,-0.0087890625,0.03692627,0.036590576,0.014404297,0.057525635,0.0018424988,-0.031921387,-0.046051025,0.049102783,-0.03805542,0.010528564,0.050567627,-0.020248413,-0.019165039,0.015609741,-0.0070610046,0.022918701,0.04748535,0.015327454,0.030776978,0.060302734,0.047576904,-0.01977539,-0.023590088,0.04159546,0.023803711,-0.021270752,-0.004573822,-0.02633667,-0.0259552,0.025787354,-0.010627747,-0.022140503,-0.065979004,0.05947876,0.05331421,0.06896973,0.026046753,0.023132324,0.0057754517,-0.019515991,0.0104904175,-0.0057754517,-0.02999878,-0.015296936,-0.062927246,0.02116394,0.0038928986,0.01689148,-0.03640747,0.0058517456,0.004638672,0.005088806,-0.008728027,0.0496521,-0.0146484375,0.001786232,0.02909851,0.012329102,0.026107788,0.03515625,-0.05206299,0.028701782,0.015625,-0.038482666,-0.014015198,0.0063819885,-0.000685215,-0.0362854,-0.06213379,-0.036956787,-0.014350891,-0.04840088,-0.06939697,-0.0027103424,-0.011741638,0.023010254,0.029174805,-0.015197754,-0.03466797,0.003118515,-0.0093307495,-0.05807495,-0.0036697388,-0.041870117,0.015838623,0.024887085,-0.018417358,0.015029907,-0.007774353,-0.005683899,0.006626129,0.021743774,-0.017654419,-0.019470215,-0.033081055,0.0041618347,-0.0048980713,0.011131287,0.0044403076,0.03366089,0.019958496,0.0309906,0.015655518,-0.0009536743,-0.019378662,-0.04840088,0.030731201,-0.044433594,0.02670288,0.02267456,-0.012779236,-0.000998497,-0.0051994324,-0.02268982,-0.012886047,0.014167786,-0.055847168,-0.01197052,0.034484863,-0.033203125,-0.01525116,-0.059783936,-0.025863647,-0.011001587,0.04373169,0.024017334,-0.004261017,-0.04458618,-0.015670776,0.015838623,-0.0036334991,0.016601562,-0.01449585,-0.020904541,-0.007896423,-0.036895752,-0.03262329,0.0019798279,0.020584106,-0.025009155,-0.035583496,-0.0010995865,-0.029220581,0.036834717,0.029586792,0.0025482178,0.022567749,-0.024124146,0.0033836365,0.0046157837,0.042236328,0.011993408,-0.014678955,-0.036895752,0.036132812,0.010101318,0.05456543,-0.04321289,-0.01473999,-0.0088272095,0.02810669,0.010009766,-0.012992859,-0.007255554,-0.0034065247,-0.024917603,-0.08929443,0.0234375,-0.01398468,0.020904541,-0.006126404,0.010559082,0.034301758,-0.0033931732,-0.0066566467,0.025985718,-0.050476074,-0.026626587,-0.026412964,-0.020324707,-0.007118225,0.0093688965,-0.008674622,0.026550293,-0.008079529,0.028839111,0.0053749084,-0.022659302,0.03881836,0.012458801,0.0013799667,0.041992188,-0.0015087128,-0.009536743,0.040771484,0.010002136,-0.026016235,0.022033691,-0.004463196,0.031204224,-0.004421234,0.039855957,0.047821045,-0.009140015,-0.0022354126,-0.0011034012,-0.001786232,-0.03302002,0.004108429,0.016433716,0.0418396,0.0012311935,-0.024871826,0.010444641,0.03567505,-0.02796936,-0.023956299,-0.0010175705,0.024597168,-0.043060303,0.0073394775,0.007972717,0.0335083,-0.026260376,0.0055618286,0.011878967,0.042114258,0.028396606,0.004108429,0.0050811768,0.012825012,-0.006580353,-0.022918701,0.01171875,-0.018859863,-0.000030994415,-0.012863159,0.0046310425,0.024856567,0.009361267,-0.0129776,-0.030471802,-0.004032135,0.019317627,-0.00831604,0.028762817,0.020751953,0.0385437,-0.022354126,0.027297974,0.021957397,-0.032592773,0.0061798096,-0.0030879974,0.029800415,0.010566711,-0.009124756,0.024139404,0.021957397,0.02607727,-0.06109619,-0.019012451,-0.0006299019,0.03781128,-0.032043457,-0.036376953,-0.05126953,-0.030853271,0.024307251,-0.0012741089,0.0016107559,0.037994385,-0.023361206,0.00051927567,0.009231567,0.012229919,-0.012992859,-0.00040650368,-0.052825928,-0.017059326,-0.008003235,0.008865356,-0.020950317,0.005054474,-0.016723633,-0.03552246,-0.002861023,-0.03326416,0.0037727356,-0.00548172,0.0011510849,0.037628174,-0.0033740997,0.016693115,-0.017028809,-0.045013428,-0.0063552856,0.016448975,0.025909424,-0.044525146,0.012641907,-0.018997192,0.0014829636,-0.006954193,-0.003370285,0.035186768,0.015930176,0.003704071,0.030181885,-0.04928589,0.046173096,-0.020553589,-0.006626129,-0.01725769,-0.030319214,-0.02192688,-0.030334473,0.0014753342,0.047851562,-0.02909851,-0.020553589,-0.031341553,-0.059265137,-0.013961792,-0.05606079,0.0077781677,0.008224487,0.026931763,-0.03149414,0.021087646,0.015838623,0.016403198,-0.002319336,-0.019378662,-0.002210617,0.019332886,0.026443481,0.0047454834,-0.041778564,-0.030395508,-0.0049476624,-0.006134033,-0.024276733,-0.03262329,-0.016693115,-0.013717651,-0.0032749176,0.0022907257,-0.010650635,-0.021530151,-0.010932922,-0.026046753,0.03717041,-0.01121521,0.0063209534,0.008880615,-0.045684814,0.0078125,0.012786865,-0.014846802,0.01776123,-0.0032253265,-0.015655518,-0.023330688,0.015075684,0.012329102,0.012268066,-0.013336182,-0.03744507,0.006454468,-0.01576233,-0.054748535,-0.008903503,-0.01663208,0.0044403076,-0.004638672,-0.0072669983,-0.04763794,0.0052871704,-0.015609741,0.006187439,0.016479492,0.018371582,0.010643005,-0.01285553,0.019805908,-0.009490967,-0.013168335,-0.04449463,0.013458252,0.010520935,-0.010322571,0.033111572,0.030151367,-0.009307861,-0.025650024,0.013031006,0.0060539246,-0.0005431175,-0.00566864,0.03152466,-0.01838684,0.015510559,0.017593384,-0.03050232,-0.03387451,-0.009010315,0.062194824,-0.0017061234,-0.003835678,0.007858276,-0.007408142,0.008735657,0.04196167,-0.026519775,0.008018494,-0.01689148,0.012535095,-0.013168335,0.025024414,-0.0035095215,0.020431519,-0.014572144,-0.052978516,0.00062036514,-0.005519867,0.00031661987,-0.060302734,-0.032440186,-0.04232788,0.011558533,-0.026306152,-0.007472992,0.0032463074,0.0137786865,-0.01826477,-0.062347412,0.0065994263,0.04510498,-0.0003554821,0.028839111,-0.016311646,0.013404846,0.03024292,-0.001033783,-0.0005168915,0.023712158,-0.0362854,-0.011222839,-0.02911377,0.03656006,-0.00017809868,-0.02394104,0.017593384,0.00088977814,0.03024292,-0.012458801,0.014419556,-0.015380859,-0.027740479,-0.0053901672,0.008125305,-0.019989014,0.0050354004,0.026351929,-0.023971558,0.027954102,-0.031280518,0.008796692,-0.0073432922,0.009376526,0.04147339,-0.030426025,0.0071029663,0.01701355,-0.0033740997,0.04534912,-0.029846191,0.047943115,0.017837524,-0.019226074,0.012374878,-0.013595581,-0.037902832,-0.026733398,-0.008361816,0.020858765,0.019851685,0.0146484375,-0.01727295,0.0032405853,0.0035076141,0.012565613,0.011024475,-0.0025691986,-0.018463135,-0.035980225,0.009048462,0.0031051636,0.021850586,0.0073890686,0.010665894,0.02758789,0.04147339,-0.029586792,-0.026062012,-0.0010557175,0.018463135,0.0023555756,-0.00844574,0.018981934,0.011543274,0.007507324,0.023788452,0.001742363,-0.03149414,-0.027297974,-0.010955811,-0.027633667,0.004207611,0.0077285767,0.028060913,0.015472412,0.003921509,-0.016174316,-0.02532959,0.002286911,-0.038085938,-0.0055122375,0.0032958984,0.013717651,0.024154663,0.014846802,0.007926941,0.022567749,-0.0001821518,0.033325195,0.015419006,-0.007835388,0.022445679,0.034698486,-0.00522995,-0.024841309,-0.01689148,-0.005088806,-0.006038666,0.008033752,-0.013717651,0.02029419,0.04034424,-0.01436615,0.032104492,0.0138168335,0.018554688,-0.0059890747,0.008422852,-0.005027771,0.012374878,0.008171082,0.016952515,-0.06085205,0.026916504,0.021255493,0.012893677,-0.0026111603,-0.010192871,-0.025909424,0.016586304,0.015289307,-0.005619049,0.04345703,-0.017456055,0.02999878,-0.0146484375,-0.00806427,0.019958496,-0.012199402,-0.035827637,0.021392822,0.00050640106,-0.0031852722,0.010002136,-0.019058228,0.045043945,-0.016555786,0.005138397,0.0015192032,-0.0231781,-0.017990112,-0.028778076,0.01689148,-0.03729248,-0.024337769,-0.0028877258,-0.017425537,0.04812622,0.045654297,0.025009155,0.03062439,0.0098724365,-0.0103302,-0.055541992,-0.056732178,0.022735596,-0.01638794,0.023284912,-0.024871826,0.03466797,0.050720215,0.012550354,0.031585693,0.030853271,0.03173828,0.00058603287,0.0017356873,-0.027542114,0.020004272,-0.03640747,0.0034294128,0.0050315857,0.04156494,-0.033691406,-0.0049858093,-0.0079574585,0.025115967,-0.012420654,0.010231018,0.07385254,0.014419556,0.002943039,0.022201538,-0.0011606216,-0.03286743,0.0050315857,-0.018066406,0.049041748,0.00843811,0.031799316,0.040496826,0.017700195,-0.007385254,0.025817871,-0.030181885,-0.01675415,0.03186035,0.024902344,-0.014129639,-0.0009069443,-0.018722534,0.006111145,-0.06137085,-0.023086548,0.015899658,0.018249512,0.016052246,-0.0058021545,-0.017593384,-0.0036563873,0.033294678,0.0003414154,0.010017395,0.0021877289,0.0037117004,0.024154663,0.0039482117,0.045837402,-0.009994507,0.017608643,-0.021911621,-0.027297974,0.009132385,-0.006275177,-0.005466461,-0.011802673,0.031280518,0.018722534,0.032165527,0.0418396,-0.019378662,0.0018167496,0.025497437,0.0071487427,0.020767212,0.045166016,0.015365601,0.0042877197,0.027770996,0.0385437,0.021575928,-0.000024795532,0.01512146,-0.0013074875,-0.017745972,0.012260437,-0.0015058517,-0.003780365,-0.009101868,0.014572144,-0.018554688,-0.012962341,0.026672363,0.027923584,0.0026397705,0.019073486,0.023117065,0.0014953613,0.0048179626,0.016616821,0.009170532,-0.019332886,0.038757324,0.023132324,0.042816162,0.005203247,0.028030396,-0.005695343,-0.012542725,-0.026107788,0.015068054,-0.037597656,0.011116028,-0.009590149,-0.01727295,-0.03387451,0.014808655,0.005207062,-0.01574707,0.031799316,0.012420654,-0.01890564,-0.003490448,0.031097412,0.03010559,-0.012908936,0.002910614,-0.016983032,0.027374268,0.05834961,0.016647339,-0.0028972626,-0.033325195,0.0031814575,0.008758545,-0.0012435913,-0.014465332,-0.0012454987,0.0032730103,-0.02911377,0.02796936,0.022476196,0.00699234,0.043151855,-0.0068244934,-0.02357483,0.0028858185,0.013923645,0.0063667297,-0.008956909,-0.010551453,0.0206604,-0.0118255615,0.023757935,0.041992188,0.010688782,0.014251709,0.0036506653,0.005619049,0.008529663,-0.015312195,0.009735107,-0.024139404,0.00007766485,-0.024505615,0.028762817,-0.025436401,-0.013511658,-0.0021953583,-0.017562866,-0.030334473,-0.022384644,0.023605347,0.0128479,0.023345947,0.029022217,0.022735596,-0.03201294,0.06561279,-0.030654907,0.025863647,-0.008453369,-0.012527466,0.06707764,0.042541504,0.03491211,0.0012493134,0.018157959,-0.030685425,-0.0012397766,0.038726807,0.016555786,0.020721436,-0.0049362183,-0.025344849,0.03955078,-0.015312195,0.01838684,-0.031066895,0.001329422,0.015899658,-0.008758545,-0.032348633,-0.0014915466,-0.0014505386,0.003768921,0.037384033,-0.030181885,-0.024475098,-0.023956299,-0.012367249,0.027297974,-0.02067566,-0.0050735474,-0.0034103394,-0.02230835,0.0024967194,0.0001462698,-0.014572144,0.016952515,0.036895752,-0.032562256,0.0021324158,-0.0035648346,0.03186035,-0.026626587,0.02658081,0.02571106,0.0050239563,0.009170532,0.039031982,-0.0022392273,0.043182373,-0.022735596,0.029769897,0.04827881,-0.0017728806,-0.012481689,0.00869751,0.015106201,-0.01449585,0.017623901,0.032684326,-0.0017957687,0.018814087,0.0075187683,0.004310608,-0.0005326271,0.020858765,-0.017166138,0.0043754578,-0.0068130493,-0.024429321,0.0026569366,0.0154418945,-0.0013570786,-0.0011615753,0.0065956116,0.0027503967,0.0019044876,0.036712646,0.021453857,-0.04168701,-0.003868103,0.005882263,-0.00007224083,-0.014831543,-0.0206604,-0.0034637451,-0.050994873,0.019515991,0.03036499,0.0051994324,0.00774765,-0.026489258,0.007499695,0.031341553,0.0098724365,0.013755798,0.0051498413,-0.008644104,0.020950317,-0.003610611,-0.008865356,-0.0119018555,-0.012565613,0.006702423,0.0287323,-0.016906738,-0.030914307,0.010475159,-0.009803772,0.0029067993,0.0013504028,0.009185791,0.037200928,0.00831604,0.009460449,-0.0010719299,0.013313293,-0.021530151,-0.029586792,-0.03036499,0.007408142,0.055114746,-0.01449585,-0.013679504,0.008979797,0.033294678,0.02229309,0.032989502,-0.0029697418,0.052703857,0.01940918,-0.005973816,-0.041992188,0.009361267,-0.027282715,-0.020736694,0.016281128,-0.0418396,-0.02130127,0.010124207,-0.0008072853,-0.0062942505,-0.020828247,0.0049438477,-0.019088745,-0.031585693,0.034301758,-0.013793945,-0.000049948692,-0.031021118,0.002784729,0.013534546,-0.033569336,-0.032470703,-0.011268616,-0.0030174255,-0.0069999695,-0.06439209,0.018875122,-0.033935547,0.008171082,-0.012321472,0.014205933,0.003238678,0.037994385,0.002822876,0.0024700165,0.009254456,0.020355225,0.015197754,0.010543823,0.030471802,-0.039520264,-0.034484863,-0.0017309189,-0.0054359436,-0.011810303,0.027923584,-0.0066337585,0.016967773,-0.0019445419,-0.00019180775,0.00076150894,-0.0021781921,-0.02407837,-0.007183075,-0.03704834,-0.041168213,-0.0022735596,0.03186035,-0.012573242,0.013031006,0.036132812,-0.008201599,-0.020629883,0.019348145,0.027633667,0.014015198,0.029953003,-0.0031261444,-0.009185791,-0.016540527,-0.007926941,-0.017913818,0.016815186,0.007194519,-0.00059890747,-0.010688782,0.026565552,0.012062073,-0.016723633,0.017074585,0.014053345,0.022476196,-0.023269653,0.03253174,0.011184692,-0.0047416687,-0.011367798,-0.00038290024,0.018981934,0.049316406,0.020462036,0.024749756,-0.0034770966,-0.0026931763,-0.0065078735,-0.00037550926,-0.0023860931,-0.022369385,-0.021713257,-0.018585205,-0.032043457,-0.0033569336,-0.007911682,0.010063171,-0.0056495667,0.036499023,0.0022201538,-0.036895752,-0.008995056,0.02607727,0.004878998,-0.0062065125,0.013061523,0.01309967,-0.009223938,-0.037353516,0.013023376,-0.07244873,-0.035705566,-0.006088257,-0.0075149536,0.013679504,-0.0034122467,-0.0070152283,0.00995636,-0.0073127747,-0.01626587,-0.009597778,0.022750854,-0.012992859,0.0046157837,-0.002035141,0.022033691,-0.013114929,0.014831543,-0.017456055,-0.000060498714,0.00995636,-0.018966675,0.022949219,0.0031700134,0.029037476,0.005088806,-0.014076233,0.009796143,-0.0009717941,-0.003753662,-0.046539307,0.009864807,0.0069732666,-0.023452759,0.009346008,-0.011871338,-0.039978027,-0.008659363,-0.009887695,-0.031021118,0.016799927,0.033935547,0.032073975,-0.0034713745,0.041381836,-0.023788452,-0.00995636,-0.013771057,0.016098022,-0.027542114,-0.0056266785,0.019577026,-0.0074501038,-0.0076560974,-0.013252258,-0.0039100647,-0.03567505,-0.029037476,-0.00081157684,-0.009803772,-0.008026123,0.025131226,0.028884888,0.036102295,0.008842468,0.016204834,0.017684937,0.0046653748,0.01927185,-0.004108429,0.04373169,-0.0027198792,-0.024398804,-0.009841919,0.004272461,0.0051994324,-0.024673462,-0.0013723373,-0.013900757,-0.040924072,0.0034103394,-0.010528564,0.03994751,-0.019714355,0.026565552,-0.023544312,-0.0132369995,-0.02444458,-0.007408142,-0.039031982,0.0055732727,0.04067993,0.0211792,0.0005440712,-0.018371582,-0.02709961,0.019592285,0.007675171,0.005996704,-0.045776367,-0.026931763,0.0045433044,0.0046844482,0.0054359436,0.018569946,-0.03186035,-0.011451721,0.010131836,0.009384155,-0.0018634796,-0.0024261475,0.0019874573,-0.0016918182,-0.009246826,0.011634827,0.028549194,-0.0048675537,-0.014404297,-0.012084961,-0.007331848,0.020446777,0.043640137,-0.0077781677,0.020721436,0.022155762,-0.035705566,0.052825928,-0.03552246,0.0052757263,-0.01486969,0.014251709,-0.031433105,-0.00032949448,0.0018415451,-0.010810852],"createdAt":"2026-04-21T18:32:12.824Z","updatedAt":"2026-04-22T04:02:25.574Z","lastSeenAt":"2026-04-22T04:02:25.574Z","tsv":"'/api/v1/emails/63':44,160 '0.02':10,24,74,150 '000':78 '0x833589fcd6edb6e08f4c7c32d4f71b54bda02913':69 '20':77 '402 payment email' '6':82 'Base network API' 'USDC API' 'accept':53 'access':36 'actual':235 'advertis':172 'ai/ml':121 'among':170 'analysi':124 'analyt':120 'api':35,85,117,203 'attach':94 'avail':195 'awar':240 'base':8,22,64,79 'behavior':245 'broader':111 'caller':92,237 'catalog':112 'categori':173 'classif':126 'connect':212 'content':218 'contract':68 'convers':143 'cost':72 'data':5,19,119 'decim':83 'describ':163 'descript':229 'discov':248 'doc':202 'document':196,197 'e.g':178 'els':191 'email':4,18,40,184,187,233 'email API' 'email-data' 'email-rel':39 'embed':127 'empir':249 'endpoint':6,20,30,52,146,156,234,243 'estim':137 'exact':176 'exampl':226 'exchang':132 'extrem':199 'feed':131 'financ':128 'function':177 'gas':136 'gate':3,17,45,116 'generat':144 'geocod':141 'header':99 'host':109 'howev':153 'infer':122 'infrastructur':139 'json':58 'json-response' 'key':86 'land':168 'limit':89 'list':148,158 'lowpaymentfee' 'lowpaymentfee.com':32,108 'must':246 'network':65 'no-api-key' 'openapi':222 'page':169,207 'pay':9,23 'pay-per-request email' 'payment':49,59,98,104 'per':11,25,75,151 'per-request-billing' 'perform':186 'post':54 'post-method' 'premium':34 'price':130,204 'prompt':214 'proof':105 'protocol':50 'provid':33,107,166 'quot':135 'rate':88,133 'readm':206 'record':185 'relat':41 'render':209 'request':12,26,55,76,152 'request/response':225 'requir':91 'resourc':42 'retriev':181 'return':57,236 'schema':223 'sentiment':123 'settl':61 'simpli':93 'someth':190 'span':118 'spars':200 'specif':43,155,183 'substant':217 'summar':125 'token':134 'unclear':193 'unit':80 'usdc':14,28,67 'usdc-base' 'use':66 'util':140 'valid':102,142,188 'wallet':213 'web3':129 'whether':179 'x':97 'x-payment':96 'x402':2,16,48,103,115 'x402 email endpoint' 'x402-gated':1,15,114 'x402-payment'","prices":[{"id":"5117b895-e38d-402b-96e9-68b08791813a","listingId":"ca2d9b1a-f4e2-4eae-ad92-ea5b4365bf8a","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/63","description":"Premium API Access","outputSchema":{"input":{"type":"http","method":"GET","discoverable":true}},"maxAmountRequired":"20000","maxTimeoutSeconds":300}],"asset_contract":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","max_timeout_seconds":300},"createdAt":"2026-04-21T18:32:12.824Z"}],"sources":[{"listingId":"ca2d9b1a-f4e2-4eae-ad92-ea5b4365bf8a","source":"x402_bazaar","sourceId":"https://lowpaymentfee.com/api/v1/emails/63","sourceUrl":"https://api.cdp.coinbase.com/platform/v2/x402/discovery/resources","isPrimary":true,"firstSeenAt":"2026-04-21T18:32:12.824Z","lastSeenAt":"2026-04-22T04:02:25.574Z"}],"details":{"listingId":"ca2d9b1a-f4e2-4eae-ad92-ea5b4365bf8a","quickStartSnippet":"curl -X POST https://lowpaymentfee.com/api/v1/emails/63 \\\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":"Endpoint returns HTTP 402 with x402 challenge requiring USDC payment on Base network","source_url":"https://lowpaymentfee.com/api/v1/emails/63"},{"claim":"maxAmountRequired is 20000 base units of USDC (6 decimals) = $0.02","source_url":"https://lowpaymentfee.com/api/v1/emails/63"},{"claim":"Provider advertises $0.02/request pricing with no API keys, no rate limits, and instant access","source_url":"https://lowpaymentfee.com"},{"claim":"USDC asset contract is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base","source_url":"https://lowpaymentfee.com/api/v1/emails/63"},{"claim":"Documentation pages render only 'Connect wallet' with no substantive content","source_url":"https://lowpaymentfee.com/docs"}],"useCases":["Retrieving email-related data behind a micropayment wall","Agent-driven workflows that need on-demand email data without subscription commitments","Testing x402 payment protocol integrations with a low-cost endpoint"],"bestFor":["Developers experimenting with x402 payment flows on Base","Agents that need pay-per-call access without API key management","Low-volume, on-demand email data retrieval"],"notFor":["High-volume email processing where per-request costs add up","Users who need detailed API documentation or guaranteed SLAs","Email sending or SMTP relay — this appears to be a data retrieval endpoint"],"kindDetails":{"x402_version":1,"resource_type":"http","bazaar_last_updated":"2026-02-17T23:13:20.145Z"},"updatedAt":"2026-04-22T04:02:25.574Z"}}