{"id":"bf94670e-4b1a-4379-b149-146c12ce7ff9","shortId":"C5rshR","kind":"x402","title":"x402-gated email API endpoint on Base, pay $0.02 per request in USDC with no API keys.","tagline":"x402-gated email API endpoint on Base, pay $0.02 per request in USDC with no API keys.","description":"This endpoint at lowpaymentfee.com provides premium API access via the x402 payment protocol. The specific resource `/api/v1/emails/1` is part of a broader platform that offers dozens of pay-per-call endpoints spanning data analytics, AI/ML inference, finance/Web3 data, and infrastructure utilities — all priced at $0.02 per request settled in USDC on the Base network.\n\nThe probed endpoint returns a valid x402 challenge (HTTP 402) requesting payment of up to 20,000 base units of USDC (0x8335…2913 on Base, 6 decimals = $0.02) via the \"exact\" scheme. No API keys, rate limits, or subscriptions are required; callers simply attach an X-PAYMENT header with a valid payment proof. The endpoint accepts POST requests and returns application/json.\n\nThe platform advertises a wide catalog of endpoints (analytics/metrics, AI sentiment analysis, text summarization, classification, embeddings, finance price feeds, exchange rates, crypto gas estimates, geocoding, validation, conversion, and generation), all at the same $0.02 price point. However, the specific `/api/v1/emails/1` endpoint is not listed on the landing page catalog, and no documentation describing its request/response schema was found. The docs, pricing, API, and README pages all returned only a \"Connect wallet\" prompt with no substantive content. The actual behavior and data returned by this email endpoint remain unknown.","tags":[],"capabilities":["x402-payment","usdc-base","pay-per-request","email-api","json-response","no-api-key"],"categories":["data","email"],"synonyms":["email API","x402 email endpoint","pay-per-call email","USDC email API","Base network API","lowpaymentfee email"],"warnings":["The /api/v1/emails/1 endpoint is not listed in the site's own API catalog — its purpose is unclear","All documentation pages (docs, pricing, API, README) returned only 'Connect wallet' with no substantive content","No request body schema or response schema is available; callers must discover behavior empirically","The platform lists many endpoint categories but provides no evidence any return real data"],"endpointUrl":"https://lowpaymentfee.com/api/v1/emails/1","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/1","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 /api/v1/emails/1 resource is not documented anywhere on the site. No request/response schema, no examples, and no docs pages contain actual content beyond 'Connect wallet'. The endpoint's purpose and data format are entirely 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":"2026-04-21T19:09:48.846Z","embedding":[-0.028030396,-0.014732361,0.057861328,0.018234253,0.030181885,-0.03753662,-0.015533447,0.031341553,0.064331055,-0.07104492,0.01979065,-0.037261963,-0.044708252,-0.028366089,-0.03781128,0.013847351,-0.0005812645,-0.028549194,-0.0413208,0.023284912,0.0473938,-0.01689148,-0.02456665,0.04638672,-0.002035141,-0.014465332,-0.0211792,0.00045776367,0.0029659271,-0.041503906,0.024154663,-0.03289795,-0.023239136,0.011711121,-0.014640808,0.023635864,-0.017227173,0.05090332,0.030151367,0.003610611,-0.0014762878,-0.048919678,0.0129852295,0.011161804,-0.0463562,-0.012001038,0.0011138916,-0.030258179,0.0014848709,0.0064849854,-0.019195557,0.0039749146,-0.010757446,0.00579834,0.00051021576,0.019943237,0.0012931824,-0.005924225,0.008811951,0.03152466,0.0034770966,-0.06488037,-0.0362854,-0.0017356873,0.011268616,0.04083252,-0.008308411,0.02508545,0.008453369,0.07897949,0.024963379,0.0501709,0.06088257,0.012931824,0.003967285,-0.029724121,0.0028533936,0.0289917,-0.030029297,-0.028442383,-0.01828003,-0.01928711,-0.036376953,-0.0031661987,-0.034484863,-0.06768799,-0.024047852,0.029144287,-0.022201538,0.028884888,-0.101135254,-0.0060768127,0.00025510788,0.012283325,-0.005569458,0.0011720657,-0.020263672,-0.0066337585,0.007293701,0.009231567,0.01828003,-0.048950195,0.017471313,0.016281128,0.041778564,0.033721924,0.019546509,0.018951416,0.011520386,-0.009552002,-0.016586304,0.0013856888,-0.016952515,-0.0037631989,0.019836426,-0.0056037903,-0.012107849,0.02041626,-0.035003662,0.019454956,-0.038604736,0.05078125,0.0021686554,-0.0037956238,-0.0039596558,-0.04425049,-0.027694702,-0.0026016235,-0.0262146,0.013374329,0.036102295,0.02456665,0.030151367,-0.014831543,-0.023269653,0.021408081,-0.01033783,-0.010276794,-0.04901123,-0.0047683716,0.05316162,-0.040039062,0.015068054,0.038513184,-0.08526611,-0.020812988,-0.042755127,0.009529114,-0.0206604,-0.012260437,0.012664795,0.0059013367,-0.005958557,-0.008293152,-0.00869751,-0.017684937,0.002155304,0.041137695,-0.0039596558,0.028961182,-0.0012168884,0.017745972,0.034301758,0.0013818741,0.0047721863,0.042999268,0.0013465881,-0.08026123,-0.0625,-0.025970459,-0.0046920776,-0.0087509155,-0.040527344,0.013290405,-0.0025367737,-0.0647583,-0.012046814,-0.002319336,-0.0068588257,-0.03640747,-0.0022258759,-0.028335571,-0.009109497,-0.00042772293,-0.05709839,-0.020843506,-0.015289307,0.061187744,0.02482605,0.015556335,0.035461426,-0.016189575,0.04232788,0.03326416,-0.024459839,-0.038330078,0.030654907,-0.007286072,0.012664795,0.032196045,0.01977539,-0.026885986,0.044403076,0.064575195,-0.0057144165,-0.012527466,0.019165039,-0.051757812,-0.04611206,-0.018661499,0.015586853,-0.0064811707,-0.019058228,0.0069999695,-0.043914795,-0.035491943,-0.004283905,0.0067749023,0.0146484375,0.062286377,-0.00015032291,0.010749817,0.019760132,0.023986816,-0.026992798,0.032043457,0.04135132,0.0155181885,-0.021316528,-0.018844604,0.020645142,0.02532959,-0.007091522,0.0141067505,-0.013046265,0.014183044,-0.009712219,-0.0013380051,0.018966675,0.00041270256,-0.038513184,-0.023529053,-0.008903503,0.015930176,0.0027980804,-0.02748108,-0.0491333,-0.061828613,0.05734253,0.058135986,0.0063095093,0.012641907,0.0035133362,-0.040527344,-0.027740479,-0.075805664,0.052459717,0.07244873,-0.00007992983,-0.017150879,0.045837402,-0.010101318,-0.018814087,0.0049552917,0.0070266724,-0.02079773,-0.011016846,-0.0035305023,-0.048919678,0.013557434,0.014465332,0.037078857,0.045806885,-0.0121536255,-0.040985107,-0.005256653,0.012466431,0.0026607513,-0.02406311,-0.010543823,0.0072669983,0.015975952,0.017471313,-0.028182983,0.014976501,-0.003250122,0.01776123,-0.008232117,0.01007843,-0.037597656,-0.01235199,0.011940002,0.015159607,-0.051574707,-0.00018787384,0.009277344,0.047088623,-0.042175293,0.041137695,-0.017196655,0.0005774498,0.04321289,0.0021533966,-0.050933838,-0.018478394,0.028411865,0.031951904,0.060791016,0.014640808,0.0073509216,-0.0057296753,0.07611084,-0.0075263977,-0.008399963,0.012260437,0.027374268,0.014625549,0.026351929,-0.05709839,-0.055023193,-0.013145447,-0.0007195473,0.031021118,-0.04147339,0.032806396,-0.0006260872,0.021896362,-0.016204834,0.00024414062,-0.038726807,-0.00258255,-0.020462036,0.0062217712,-0.0289917,-0.006580353,0.015602112,0.006340027,-0.00019574165,-0.001490593,0.040100098,-0.006576538,0.0022735596,-0.013977051,-0.047058105,-0.037231445,-0.013442993,0.0009293556,0.021392822,0.012107849,0.031066895,-0.059020996,0.024261475,0.029556274,0.007255554,0.03326416,-0.009918213,0.023208618,-0.066223145,-0.03692627,-0.012283325,-0.015609741,0.029846191,0.037628174,0.009994507,0.061462402,0.003835678,-0.02545166,-0.05886841,0.03970337,-0.041259766,0.008506775,0.051239014,-0.016036987,-0.029846191,0.017562866,-0.020614624,0.00844574,0.044952393,0.017959595,0.040863037,0.070251465,0.055480957,-0.015686035,-0.008979797,0.03543091,0.013809204,-0.005935669,-0.010940552,-0.018951416,-0.03515625,0.034454346,-0.018081665,-0.025360107,-0.07598877,0.07800293,0.051513672,0.08050537,0.024337769,0.018112183,0.033966064,-0.012527466,0.004989624,-0.0043678284,-0.028396606,-0.02532959,-0.049804688,0.014167786,0.00023663044,0.014038086,-0.033599854,0.010978699,0.0078048706,0.009292603,-0.01838684,0.06616211,-0.011680603,-0.0061569214,0.024261475,0.016464233,0.039794922,0.031677246,-0.045440674,0.031402588,0.028930664,-0.03289795,0.0009059906,0.019714355,-0.004257202,-0.0146484375,-0.06072998,-0.04425049,-0.017791748,-0.028656006,-0.06774902,0.0020103455,-0.0048103333,0.028244019,0.04675293,-0.02154541,-0.02432251,0.0033607483,-0.0033988953,-0.06341553,-0.008300781,-0.032806396,0.010101318,0.029403687,-0.028320312,0.012428284,-0.0071640015,-0.001159668,-0.015419006,0.0234375,-0.0071907043,-0.0018024445,-0.042938232,0.024383545,-0.005264282,0.014923096,0.019241333,0.029296875,0.021484375,0.033569336,0.018920898,-0.0054969788,-0.029953003,-0.039886475,0.03289795,-0.044067383,0.021896362,0.027511597,-0.012886047,0.00048089027,-0.006702423,-0.02998352,-0.025558472,0.023071289,-0.040374756,-0.00048208237,0.02722168,-0.03427124,-0.016189575,-0.038024902,-0.025360107,-0.019104004,0.051605225,0.015853882,-0.007911682,-0.047332764,-0.006465912,0.028915405,-0.005466461,0.009895325,-0.014198303,-0.009483337,-0.0018100739,-0.02947998,-0.024139404,-0.0018863678,0.028503418,-0.023788452,-0.01751709,-0.0028419495,-0.008666992,0.035461426,0.017227173,0.011558533,0.031204224,-0.028808594,-0.0019350052,-0.0008029938,0.029541016,0.015289307,-0.004562378,-0.03213501,0.025650024,-0.005748749,0.051361084,-0.032043457,-0.008148193,0.0016851425,0.028503418,0.012046814,-0.00818634,-0.00025606155,-0.009101868,-0.03744507,-0.08215332,0.027923584,-0.013900757,0.019714355,0.009590149,0.021728516,0.024215698,-0.006324768,-0.0074310303,0.018707275,-0.039611816,-0.03137207,-0.02407837,-0.017242432,-0.011955261,0.0025157928,-0.012161255,0.016098022,0.0011968613,0.026229858,0.011543274,-0.015655518,0.027816772,0.012908936,-0.0050315857,0.032348633,-0.007774353,0.00047683716,0.041381836,0.0048332214,-0.032592773,0.015930176,0.0028743744,0.017822266,-0.0034675598,0.04272461,0.047180176,-0.0060043335,0.0025577545,-0.00041890144,-0.0112838745,-0.027282715,0.009811401,0.019195557,0.0234375,-0.0022621155,-0.039642334,0.017974854,0.014945984,-0.033111572,-0.020309448,0.0033798218,0.030838013,-0.037353516,0.019470215,0.017669678,0.044189453,-0.024917603,0.006767273,0.013389587,0.038482666,0.036224365,0.006954193,-0.002544403,0.013702393,-0.0064048767,-0.005706787,0.0035190582,-0.013847351,0.010620117,-0.0095825195,0.004699707,0.026382446,0.019866943,-0.013427734,-0.027816772,-0.0071907043,0.011634827,-0.024215698,0.021835327,0.019088745,0.04284668,-0.04031372,0.02758789,0.021514893,-0.034301758,-0.0009508133,-0.011314392,0.040283203,0.015052795,-0.0062942505,0.024475098,0.018203735,0.025360107,-0.05630493,-0.0155181885,-0.0004761219,0.02909851,-0.029327393,-0.044036865,-0.040985107,-0.008773804,0.032226562,0.007610321,0.0021038055,0.030761719,-0.018920898,0.008659363,0.01927185,0.0065078735,-0.018325806,0.0073051453,-0.044769287,-0.018356323,-0.0039138794,0.01020813,-0.022140503,0.012001038,-0.017425537,-0.034118652,-0.00018501282,-0.022506714,-0.00064373016,0.00036406517,0.011909485,0.043945312,-0.004825592,0.013664246,-0.027175903,-0.0390625,-0.00044488907,0.009223938,0.019805908,-0.045776367,0.013900757,-0.014480591,-0.0039405823,-0.005027771,0.0023441315,0.02154541,0.00843811,0.006587982,0.028503418,-0.055541992,0.03463745,-0.013175964,0.0016365051,-0.017410278,-0.023376465,-0.022140503,-0.019134521,-0.0035915375,0.049438477,-0.029876709,-0.021850586,-0.030029297,-0.057159424,-0.012123108,-0.06512451,0.0119018555,0.007648468,0.025665283,-0.02053833,0.013427734,0.015548706,0.0032043457,-0.013793945,-0.00062799454,-0.009269714,0.021514893,0.029815674,0.004924774,-0.03552246,-0.030075073,-0.007396698,-0.0069236755,-0.02142334,-0.048431396,-0.023483276,0.0009937286,-0.0004930496,-0.0073661804,-0.0063972473,-0.032165527,-0.0045051575,-0.039642334,0.031677246,-0.0050964355,0.005558014,0.003873825,-0.04559326,-0.0005764961,0.017425537,-0.018920898,0.022460938,-0.0025157928,-0.0075149536,-0.024749756,-0.00092697144,0.018936157,0.024246216,-0.016998291,-0.018966675,0.0014228821,-0.027511597,-0.0569458,-0.0017471313,-0.0071907043,0.0060653687,0.004322052,-0.012588501,-0.05340576,0.004676819,-0.00982666,-0.0058670044,0.02532959,0.011489868,0.0058135986,0.0084991455,0.015716553,-0.014251709,-0.008926392,-0.043151855,0.018737793,0.010688782,-0.014251709,0.03475952,0.029281616,-0.006980896,-0.018814087,0.016983032,0.0033092499,-0.0012207031,-0.0066566467,0.008605957,-0.0234375,0.022918701,0.010025024,-0.031982422,-0.031036377,-0.004386902,0.073913574,0.0021820068,-0.0045928955,0.010414124,-0.02267456,0.013244629,0.03640747,-0.034454346,0.0034103394,-0.019073486,0.0158844,-0.024398804,0.026626587,0.00021576881,0.012840271,-0.02784729,-0.052734375,-0.003063202,-0.0015983582,-0.0033569336,-0.05053711,-0.037475586,-0.04269409,0.008224487,-0.02722168,-0.0074501038,-0.0016078949,0.0051078796,-0.020401001,-0.07232666,0.008216858,0.051727295,0.0012207031,0.02911377,-0.023147583,0.002494812,0.021514893,-0.019439697,0.004016876,0.023803711,-0.032928467,-0.009109497,-0.027542114,0.03253174,-0.0056991577,-0.01928711,0.023422241,-0.00579834,0.033355713,-0.020431519,0.021102905,-0.021102905,-0.0115737915,-0.013313293,0.004497528,-0.012809753,0.0022716522,0.031219482,-0.03237915,0.029556274,-0.015312195,0.0019111633,-0.008781433,0.018981934,0.041046143,-0.033721924,-0.012817383,0.019073486,-0.011268616,0.038146973,-0.034240723,0.045074463,0.016189575,-0.027542114,0.008346558,-0.014518738,-0.028549194,-0.030853271,-0.019332886,0.031555176,0.017074585,0.0037441254,-0.0053634644,0.0009994507,0.004749298,0.007820129,0.0034160614,-0.0038700104,-0.022705078,-0.029693604,0.0010032654,0.00749588,0.011802673,0.011672974,0.015602112,0.019882202,0.046691895,-0.017120361,-0.017410278,-0.010978699,0.032348633,0.0025157928,-0.0101623535,0.023147583,0.005970001,0.0074691772,0.02230835,0.015220642,-0.031982422,-0.021652222,-0.021621704,-0.023529053,0.010421753,0.007080078,0.017913818,0.0029907227,0.0018787384,-0.0074043274,-0.036743164,0.002149582,-0.03842163,-0.019851685,0.012130737,0.009262085,0.013389587,-0.001291275,0.0040664673,0.020812988,-0.0018835068,0.027328491,0.013648987,-0.009552002,0.0362854,0.040100098,-0.009971619,-0.027175903,-0.012550354,-0.0034065247,-0.011810303,-0.002046585,-0.018493652,0.017929077,0.043121338,-0.019378662,0.021530151,-0.0033607483,0.013664246,-0.006362915,0.010627747,-0.0076179504,0.01890564,-0.0008263588,0.034088135,-0.061157227,0.022827148,0.021209717,0.009376526,-0.01789856,-0.01285553,-0.024902344,0.010421753,0.0074882507,-0.017318726,0.034851074,-0.006980896,0.034240723,-0.0102005005,-0.018173218,0.014427185,-0.022033691,-0.034362793,0.03262329,-0.006324768,-0.005970001,0.010665894,-0.009376526,0.04296875,-0.021942139,0.0051651,0.008415222,-0.011108398,-0.0146102905,-0.019805908,0.012550354,-0.024978638,-0.020904541,-0.002527237,-0.008300781,0.057769775,0.043701172,0.02609253,0.0335083,0.006137848,-0.005039215,-0.051605225,-0.049346924,0.013114929,-0.024765015,0.027633667,-0.01864624,0.053466797,0.035064697,0.01675415,0.03173828,0.028762817,0.03967285,-0.010345459,0.016235352,-0.023422241,0.024902344,-0.015235901,0.010375977,-0.0034313202,0.031433105,-0.03640747,0.0020046234,0.0013151169,0.02330017,-0.021636963,0.028579712,0.073791504,0.021087646,-0.0057907104,0.02748108,0.0052757263,-0.026107788,-0.0037174225,-0.014587402,0.047729492,0.012809753,0.03314209,0.049591064,0.00982666,-0.0035953522,0.019714355,-0.031951904,-0.026779175,0.04269409,0.026885986,-0.008201599,-0.0067596436,-0.0077285767,0.010673523,-0.055755615,-0.027816772,0.016326904,0.0054130554,0.002368927,-0.009864807,-0.009483337,-0.004447937,0.028366089,0.008834839,0.012825012,0.0007944107,0.0118255615,0.024932861,0.00016784668,0.041809082,-0.0016422272,0.01158905,-0.027297974,-0.025283813,0.012504578,0.00060367584,-0.015182495,-0.01940918,0.0287323,0.012794495,0.037109375,0.030593872,-0.01637268,0.004638672,0.031341553,0.01776123,0.019210815,0.053344727,0.024490356,-0.0064735413,0.03237915,0.031021118,0.016845703,-0.0093688965,0.014381409,0.0107421875,0.0069274902,0.0062942505,-0.006702423,0.010673523,-0.0055274963,0.011741638,-0.018203735,-0.0115737915,0.014259338,0.028839111,0.0013008118,0.002714157,0.015991211,0.007881165,0.0019702911,0.014297485,-0.001156807,-0.015029907,0.03692627,0.025619507,0.044281006,-0.0066452026,0.023208618,-0.0026569366,-0.011558533,-0.021347046,0.018630981,-0.055603027,0.011444092,-0.009468079,-0.015716553,-0.03933716,0.018920898,0.0137786865,-0.011581421,0.036315918,0.01927185,-0.016830444,-0.002380371,0.029800415,0.019073486,-0.008125305,-0.0019950867,-0.023544312,0.02468872,0.05532837,0.009460449,-0.009597778,-0.038238525,0.005908966,0.014831543,-0.0064811707,-0.0059509277,-0.0013666153,-0.011138916,-0.041809082,0.019836426,0.029953003,0.01184845,0.040771484,-0.011413574,-0.025817871,0.0051612854,0.016418457,-0.0026817322,-0.0084991455,-0.020553589,0.023269653,-0.013015747,0.04449463,0.04626465,0.014274597,0.025100708,-0.0010929108,-0.0071907043,0.0045700073,-0.011199951,0.010688782,-0.02420044,0.004360199,-0.015426636,0.03540039,-0.011100769,-0.020706177,-0.008224487,-0.02520752,-0.029556274,-0.013168335,0.019180298,0.014205933,0.03390503,0.030914307,0.027618408,-0.026855469,0.06427002,-0.022918701,0.048095703,-0.00844574,-0.010894775,0.06323242,0.0385437,0.026748657,0.0078048706,0.02067566,-0.029205322,0.004333496,0.03286743,0.030761719,0.012283325,-0.00010102987,-0.024597168,0.028884888,0.00038671494,0.024154663,-0.032043457,0.007713318,0.015075684,-0.00919342,-0.027297974,-0.005645752,-0.002286911,-0.00014042854,0.04147339,-0.03353882,-0.02722168,-0.016082764,-0.017501831,0.0287323,-0.012939453,-0.0035820007,-0.0064315796,-0.016357422,-0.0001667738,-0.0014591217,-0.023010254,0.0064697266,0.040802002,-0.03164673,-0.003944397,0.0027275085,0.024749756,-0.023376465,0.035736084,0.033172607,-0.0016412735,0.003818512,0.040161133,-0.0034999847,0.032806396,-0.020263672,0.037963867,0.043548584,0.004550934,-0.012031555,0.018051147,0.021133423,-0.010757446,0.017150879,0.03286743,-0.002407074,0.0065345764,0.010276794,0.0016174316,0.0011835098,0.016189575,-0.027191162,0.01171875,-0.018737793,-0.021621704,0.0070533752,0.01285553,-0.00018310547,-0.00085544586,0.00054979324,-0.0045928955,0.006122589,0.035705566,0.023956299,-0.029205322,-0.002325058,-0.00066423416,0.0037670135,-0.027023315,-0.017074585,0.0025920868,-0.04824829,0.019058228,0.030212402,0.0077590942,0.0010557175,-0.018661499,0.00009030104,0.032165527,0.01727295,0.0118637085,0.009155273,0.00043582916,0.007083893,-0.0051116943,-0.015930176,-0.012008667,-0.017333984,-0.00022995472,0.031921387,-0.011764526,-0.025283813,0.01626587,-0.0030059814,-0.0028533936,0.0008072853,-0.0024909973,0.0362854,0.0012683868,0.008079529,-0.0076828003,0.0070343018,-0.02381897,-0.02468872,-0.025527954,0.008728027,0.057037354,-0.013214111,-0.025390625,0.015823364,0.035583496,0.015106201,0.041046143,-0.005176544,0.053619385,0.0116119385,-0.0054092407,-0.0345459,0.0033874512,-0.02368164,-0.019821167,0.01083374,-0.038726807,-0.025100708,0.01473999,0.004272461,-0.0058898926,-0.022613525,-0.0063438416,-0.013809204,-0.032409668,0.026367188,-0.005088806,0.0020179749,-0.031219482,-0.0030879974,0.005252838,-0.02331543,-0.038757324,-0.010314941,-0.0013246536,-0.019195557,-0.068603516,0.015159607,-0.023284912,0.013160706,-0.010307312,0.012962341,-0.008041382,0.03552246,-0.007007599,0.0032043457,0.0021343231,0.027252197,0.022659302,0.00016951561,0.04220581,-0.04434204,-0.03616333,-0.014335632,0.003921509,-0.027999878,0.027557373,-0.0053634644,0.02229309,0.011405945,-0.0046691895,0.0025806427,-0.006011963,-0.022979736,-0.01638794,-0.032836914,-0.03744507,0.020553589,0.026046753,0.0024871826,0.0041618347,0.03555298,-0.01109314,-0.013755798,0.0124053955,0.039001465,0.0019798279,0.03161621,-0.0028038025,-0.0056152344,-0.024459839,-0.010391235,-0.025344849,0.013114929,0.00970459,0.0061683655,-0.013206482,0.027694702,0.010223389,-0.020980835,0.01398468,0.017410278,0.016983032,-0.0079574585,0.034301758,0.0057640076,-0.0018796921,-0.015426636,0.001159668,0.009994507,0.048065186,0.023788452,0.016403198,-0.010406494,-0.00011861324,-0.00026607513,0.0029239655,0.004295349,-0.017562866,-0.033111572,-0.017150879,-0.040008545,0.00699234,-0.0077667236,0.0105896,-0.0025920868,0.02571106,-0.004333496,-0.03729248,-0.015258789,0.02432251,-0.002035141,-0.00497818,-0.00019669533,0.021911621,-0.004638672,-0.039367676,0.017227173,-0.059753418,-0.047210693,-0.006462097,-0.016296387,0.015068054,0.004776001,-0.005569458,0.010688782,-0.011932373,-0.011550903,0.00079107285,0.027801514,-0.009033203,-0.005340576,0.0110321045,0.027694702,-0.0154418945,0.0070648193,-0.025375366,-0.009796143,0.0071372986,-0.014297485,0.029067993,-0.008529663,0.016281128,-0.0035953522,-0.018447876,0.021957397,-0.0049972534,0.0057868958,-0.049316406,0.003643036,0.010414124,-0.022918701,0.024215698,-0.013160706,-0.046905518,-0.014289856,-0.020858765,-0.023040771,0.01651001,0.032043457,0.028076172,0.010856628,0.03729248,-0.030548096,-0.014862061,0.003824234,0.009994507,-0.02998352,-0.006088257,0.023727417,-0.0012378693,-0.008529663,-0.012779236,0.008415222,-0.032684326,-0.03488159,0.007461548,-0.008728027,-0.016860962,0.019119263,0.026168823,0.043823242,0.0004911423,0.007835388,0.018859863,-0.0037441254,0.032318115,-0.012680054,0.0463562,-0.006580353,-0.03475952,-0.001537323,0.0071640015,-0.0078125,-0.01335144,-0.0064849854,-0.0034809113,-0.039916992,0.0059013367,-0.007167816,0.034362793,-0.018127441,0.022613525,-0.021850586,-0.011222839,-0.03189087,-0.00630188,-0.048553467,0.009666443,0.038391113,0.027328491,0.005634308,-0.018157959,-0.030548096,0.024017334,0.0127334595,0.0046081543,-0.051239014,-0.027816772,0.0018234253,0.0028247833,0.014297485,0.020706177,-0.033416748,-0.01789856,0.0044021606,0.0016965866,-0.0019893646,-0.004463196,0.008262634,0.00042581558,-0.006072998,0.011154175,0.032562256,0.0051460266,-0.0127334595,-0.012458801,-0.006034851,0.031677246,0.039611816,-0.019760132,0.018005371,0.025390625,-0.04373169,0.055267334,-0.032562256,0.018341064,-0.016983032,0.009971619,-0.030471802,-0.022338867,-0.001449585,-0.010620117],"createdAt":"2026-04-21T18:32:10.658Z","updatedAt":"2026-04-22T13:32:09.255Z","lastSeenAt":"2026-04-22T13:32:09.255Z","tsv":"'/api/v1/emails/1':53,193 '0.02':10,28,82,119,187 '000':108 '0x8335':113 '20':107 '2913':114 '402':101 '6':117 'Base network API' 'USDC email API' 'accept':148 'access':44 'actual':231 'advertis':156 'ai':163 'ai/ml':72 'analysi':165 'analyt':71 'analytics/metrics':162 'api':5,17,23,35,43,125,215 'application/json':153 'attach':135 'base':8,26,90,109,116 'behavior':232 'broader':58 'call':67 'caller':133 'catalog':159,202 'challeng':99 'classif':168 'connect':223 'content':229 'convers':180 'crypto':175 'data':70,75,234 'decim':118 'describ':206 'doc':213 'document':205 'dozen':62 'email':4,22,238 'email API' 'email-api' 'embed':169 'endpoint':6,24,38,68,94,147,161,194,239 'estim':177 'exact':122 'exchang':173 'feed':172 'financ':170 'finance/web3':74 'found':211 'gas':176 'gate':3,21 'generat':182 'geocod':178 'header':140 'howev':190 'http':100 'infer':73 'infrastructur':77 'json-response' 'key':18,36,126 'land':200 'limit':128 'list':197 'lowpaymentfee email' 'lowpaymentfee.com':40 'network':91 'no-api-key' 'offer':61 'page':201,218 'part':55 'pay':9,27,65 'pay-per-cal':64 'pay-per-call email' 'pay-per-request' 'payment':48,103,139,144 'per':11,29,66,83 'platform':59,155 'point':189 'post':149 'premium':42 'price':80,171,188,214 'probe':93 'prompt':225 'proof':145 'protocol':49 'provid':41 'rate':127,174 'readm':217 'remain':240 'request':12,30,84,102,150 'request/response':208 'requir':132 'resourc':52 'return':95,152,220,235 'schema':209 'scheme':123 'sentiment':164 'settl':85 'simpli':134 'span':69 'specif':51,192 'subscript':130 'substant':228 'summar':167 'text':166 'unit':110 'unknown':241 'usdc':14,32,87,112 'usdc-base' 'util':78 'valid':97,143,179 'via':45,120 'wallet':224 'wide':158 'x':138 'x-payment':137 'x402':2,20,47,98 'x402 email endpoint' 'x402-gated':1,19 'x402-payment'","prices":[{"id":"0cf135c0-b040-41f0-a538-9aa64685f4f4","listingId":"bf94670e-4b1a-4379-b149-146c12ce7ff9","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/1","description":"Premium API Access","outputSchema":{"input":{"type":"http","method":"GET","discoverable":true}},"maxAmountRequired":"20000","maxTimeoutSeconds":300}],"asset_contract":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","max_timeout_seconds":300},"createdAt":"2026-04-21T18:32:10.658Z"}],"sources":[{"listingId":"bf94670e-4b1a-4379-b149-146c12ce7ff9","source":"x402_bazaar","sourceId":"https://lowpaymentfee.com/api/v1/emails/1","sourceUrl":"https://api.cdp.coinbase.com/platform/v2/x402/discovery/resources","isPrimary":true,"firstSeenAt":"2026-04-21T18:32:10.658Z","lastSeenAt":"2026-04-22T13:32:09.255Z"}],"details":{"listingId":"bf94670e-4b1a-4379-b149-146c12ce7ff9","quickStartSnippet":"curl -X POST https://lowpaymentfee.com/api/v1/emails/1 \\\n  -H \"X-PAYMENT: <x402-payment-proof>\" \\\n  -H \"Content-Type: application/json\"","exampleRequest":null,"exampleResponse":null,"schema":{"input":{"type":"http","method":"GET","discoverable":true}},"openapiUrl":null,"agentsTxtUrl":null,"citations":[{"claim":"The endpoint returns a valid x402 challenge with maxAmountRequired of 20000 base units of USDC on Base","source_url":"https://lowpaymentfee.com/api/v1/emails/1"},{"claim":"The platform advertises $0.02 per request pricing with no API keys, no rate limits, and instant access on Base network","source_url":"https://lowpaymentfee.com"},{"claim":"The USDC asset address is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base","source_url":"https://lowpaymentfee.com/api/v1/emails/1"},{"claim":"Docs, pricing, API, and README pages all returned only 'Connect wallet' with no documentation content","source_url":"https://lowpaymentfee.com/docs"}],"useCases":["Fetching email data or records via a single paid API call","Integrating pay-per-use email functionality into agent workflows","Accessing premium email content without subscription or API key management"],"bestFor":["Agents needing one-off email data lookups with crypto micropayments","Developers wanting zero-signup API access on Base","Workflows requiring x402-compatible endpoints"],"notFor":["Users needing detailed API documentation or schema guarantees before calling","High-volume email operations where per-call pricing is inefficient","Non-crypto users who cannot settle payments in USDC on Base"],"kindDetails":{"x402_version":1,"resource_type":"http","bazaar_last_updated":"2026-02-17T23:13:21.94Z"},"updatedAt":"2026-04-22T13:32:09.255Z"}}