{"id":"629a6086-4f56-4e9a-a563-9e0d1872dff3","shortId":"UXvmhQ","kind":"x402","title":"Pay-per-call API suite on Base (USDC) covering data, AI, finance, and utility endpoints at $0.02/request.","tagline":"Pay-per-call API suite on Base (USDC) covering data, AI, finance, and utility endpoints at $0.02/request.","description":"lowpaymentfee.com is an x402-enabled API platform that offers a broad collection of endpoints spanning data analytics, AI/ML inference, finance/Web3 market data, and general utility services. Every endpoint is priced at $0.02 per request, settled in USDC on the Base network via the x402 payment protocol. There are no API keys, no rate limits, and no minimum commitments — callers simply attach an X-PAYMENT header with a valid x402 payment proof.\n\nThe specific endpoint probed here (`/api/v1/transactions/250`) is listed as \"Premium API Access\" and returns a 402 challenge requesting up to 20,000 base units of USDC (i.e., $0.02) on Base. The site 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 share the same $0.02 price point.\n\nDocumentation is extremely sparse — the /docs, /api, /pricing, and /README pages all render only a \"Connect wallet\" prompt with no further technical detail. No OpenAPI spec, request/response schemas, or usage examples are available from the crawl. Because of this, the actual behavior and output format of each endpoint cannot be verified from public documentation alone.","tags":[],"capabilities":["x402-payment","usdc-base","pay-per-request","data-analytics","ai-sentiment","ai-summarization","ai-classification","ai-embeddings","price-feeds","exchange-rates","gas-estimates","geocoding","validation","conversion"],"categories":["ai","finance","data","utilities"],"synonyms":["low payment fee API","x402 API","pay-per-call API","USDC micropayment API","Base network API","402 payment API","micro-transaction API"],"warnings":["Documentation pages (/docs, /api, /pricing, /README) all render only 'Connect wallet' with no technical content","No OpenAPI or JSON schema available — request and response formats are unknown","The specific endpoint /api/v1/transactions/250 is labeled 'Premium API Access' but its actual function is undocumented","Cannot verify that the advertised AI, finance, data, and utility endpoints actually return meaningful data"],"endpointUrl":"https://lowpaymentfee.com/api/v1/transactions/250","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/transactions/250","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 beyond a wallet-connect prompt, and no examples. The actual functionality behind 'Premium API Access' and the other listed endpoints is unverifiable from public sources.","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":"2026-04-19T12:34:32.031Z","embedding":[-0.038024902,-0.038513184,0.044189453,0.00409317,0.0068206787,-0.026687622,-0.027023315,0.023223877,0.07116699,-0.06222534,0.032165527,-0.04736328,-0.022598267,-0.0357666,-0.006652832,0.01209259,-0.008377075,0.012184143,-0.037719727,0.02835083,0.028656006,-0.020202637,-0.028244019,0.01637268,-0.008369446,-0.023391724,-0.0048828125,-0.0102005005,-0.026550293,-0.053649902,0.0574646,-0.028656006,-0.0047073364,-0.003025055,-0.011299133,-0.0061416626,-0.0046844482,0.032409668,0.04071045,-0.01574707,0.0065727234,-0.053497314,0.011886597,-0.022659302,-0.04525757,-0.012168884,0.026473999,-0.032409668,0.012649536,-0.0019416809,-0.055603027,-0.0009675026,-0.010383606,0.015556335,0.0052719116,0.019607544,-0.0062446594,-0.0037593842,0.018814087,-0.004878998,-0.000034034252,-0.058685303,-0.021347046,-0.0017309189,-0.010169983,0.05117798,-0.0015077591,0.04525757,0.0037784576,0.05581665,0.029266357,0.053009033,0.029541016,0.015426636,0.010528564,-0.002292633,-0.018310547,0.06149292,-0.018600464,-0.028701782,-0.012992859,-0.01689148,-0.048858643,-0.0027275085,-0.013549805,-0.053863525,-0.027420044,0.026794434,-0.02798462,0.03074646,-0.07330322,-0.01084137,-0.015159607,-0.002073288,0.00042009354,-0.0033473969,-0.0025749207,0.0055732727,-0.016616821,0.017471313,-0.0016508102,-0.040283203,0.015960693,0.012916565,0.037902832,0.04425049,0.022567749,0.015464783,0.0025405884,0.002784729,-0.035308838,0.01576233,-0.011100769,-0.0069351196,0.002729416,0.016342163,-0.018447876,0.013519287,-0.03274536,0.010772705,-0.053222656,0.053527832,0.024673462,0.008460999,0.005153656,-0.058380127,-0.02822876,0.0018558502,-0.029190063,-0.017196655,0.016220093,0.021636963,0.027023315,-0.010025024,-0.028442383,0.012519836,-0.015220642,-0.0017871857,-0.044677734,-0.034057617,0.030975342,-0.025222778,0.020004272,0.039001465,-0.10546875,-0.019119263,-0.045318604,0.008110046,-0.026397705,-0.008552551,0.0037212372,0.012138367,-0.035369873,-0.02142334,-0.014862061,-0.031341553,-0.005554199,0.038879395,-0.0155181885,0.030288696,-0.025253296,0.029876709,0.01209259,0.0069885254,0.012519836,0.032318115,-0.014030457,-0.081970215,-0.0869751,-0.028945923,0.009536743,-0.031951904,-0.028686523,-0.0069618225,-0.010154724,-0.074279785,-0.025604248,-0.009727478,0.007209778,-0.043640137,-0.011566162,-0.030227661,0.011940002,-0.011993408,-0.042633057,-0.019622803,-0.028900146,0.052001953,0.023895264,0.022018433,0.03201294,-0.0015869141,0.05532837,0.028701782,-0.008163452,-0.01361084,0.000787735,-0.016921997,0.02835083,-0.0020217896,0.01424408,-0.0335083,0.04711914,0.06866455,-0.004219055,-0.028198242,-0.0012960434,-0.053009033,-0.038360596,-0.033416748,0.026382446,0.029968262,-0.008079529,0.04348755,-0.041625977,-0.03604126,-0.0058135986,0.01020813,0.010986328,0.07244873,0.015960693,-0.00039601326,0.037902832,0.00969696,-0.049621582,0.04348755,0.042510986,0.007659912,-0.015586853,-0.042266846,0.03479004,0.035736084,-0.027404785,0.018478394,-0.012374878,0.026977539,-0.008506775,0.0023326874,0.021911621,-0.018157959,-0.029266357,-0.01121521,-0.020202637,0.02986145,0.018325806,-0.021194458,-0.034423828,-0.074645996,0.059814453,0.031219482,0.030075073,-0.01826477,-0.0043678284,-0.028701782,-0.008834839,-0.0690918,0.06121826,0.08215332,0.0031204224,0.0053138733,0.020629883,0.011421204,-0.03704834,-0.002614975,-0.010673523,-0.025512695,-0.0061683655,0.014099121,-0.040649414,0.0006828308,0.025619507,0.024902344,0.05718994,-0.017333984,-0.04345703,-0.027389526,-0.0065307617,0.0021247864,-0.0362854,0.015304565,-0.010955811,0.011619568,0.035949707,0.0075798035,0.017608643,0.00035953522,0.009300232,-0.008171082,0.0065612793,-0.024673462,-0.017456055,0.017501831,0.0054969788,-0.06604004,0.01939392,-0.0046806335,0.064208984,-0.048187256,0.038726807,-0.01763916,0.0121154785,0.049804688,-0.0035076141,-0.03665161,0.015655518,0.035003662,0.014511108,0.040039062,0.0064315796,-0.03186035,-0.0032253265,0.08892822,-0.0063667297,-0.0033607483,0.015167236,0.0044555664,0.031341553,-0.01852417,-0.049957275,-0.04071045,0.005016327,-0.03201294,0.027236938,-0.01638794,0.027359009,-0.0095825195,-0.0065612793,-0.020858765,-0.003665924,-0.02758789,0.012420654,-0.013282776,0.008514404,-0.011291504,-0.03665161,0.008712769,0.014953613,-0.017120361,-0.003791809,0.059509277,0.011894226,-0.01689148,-0.032226562,-0.033599854,0.0007019043,-0.016403198,0.026535034,0.024139404,0.022506714,0.053649902,-0.020690918,0.0026779175,0.01335907,0.026565552,0.027954102,-0.0051345825,0.0017108917,-0.058532715,-0.036834717,-0.030212402,-0.04336548,0.03186035,0.032684326,-0.0036678314,0.051330566,0.016159058,-0.019104004,-0.03387451,0.0072288513,-0.050994873,0.008155823,0.030929565,-0.0011234283,-0.026306152,-0.0078125,-0.005191803,0.0014305115,0.04647827,0.023284912,0.022125244,0.05859375,0.042877197,0.006942749,0.021575928,0.009376526,0.032836914,0.018295288,-0.0058784485,-0.03845215,-0.015144348,0.03125,-0.028442383,-0.030212402,-0.06536865,0.066345215,0.035949707,0.08392334,0.01600647,0.01448822,0.025665283,-0.0070762634,-0.0011453629,-0.020828247,-0.02293396,-0.027770996,-0.022598267,0.036376953,-0.01802063,0.0035171509,-0.013412476,0.04119873,-0.0032081604,0.018814087,-0.019317627,0.045898438,-0.017959595,-0.0070610046,0.01335907,0.011062622,0.053100586,0.051330566,-0.04031372,0.02645874,0.021453857,-0.041900635,0.013801575,0.051452637,-0.006641388,-0.01083374,-0.04940796,-0.029968262,-0.0050811768,-0.0076179504,-0.04144287,-0.0009112358,0.0060806274,0.020004272,0.0287323,-0.006454468,-0.014152527,-0.005470276,-0.026000977,-0.053649902,0.00014126301,-0.04949951,0.0026168823,0.034240723,-0.02986145,-0.0045051575,-0.00894165,-0.0075531006,-0.012413025,0.0019330978,0.031921387,-0.00038695335,-0.051879883,0.05130005,-0.0037288666,0.016448975,0.022979736,0.042022705,0.028381348,0.018951416,0.053985596,0.0074157715,-0.015777588,-0.05718994,0.016540527,-0.0496521,0.011138916,0.025665283,-0.03086853,-0.006504059,-0.0063476562,-0.03378296,-0.029541016,0.017913818,-0.017929077,-0.00019395351,0.014343262,-0.026382446,-0.040130615,-0.06719971,-0.004383087,-0.005203247,0.061309814,0.0090408325,0.00017237663,-0.05014038,0.003074646,0.02468872,-0.009017944,0.039001465,-0.015533447,0.0011587143,0.0028495789,-0.040100098,0.004486084,-0.0236969,0.034484863,-0.008232117,-0.010353088,0.012420654,0.009552002,0.023117065,0.0021152496,-0.003358841,0.010932922,-0.028656006,-0.011993408,-0.01159668,0.021987915,0.018447876,-0.0058021545,-0.037475586,0.0357666,0.019042969,0.042938232,-0.022766113,-0.008560181,-0.009422302,0.007896423,0.021469116,-0.02116394,-0.01071167,-0.017303467,-0.043701172,-0.06451416,0.039215088,-0.016220093,0.029052734,0.025115967,0.015640259,0.023040771,-0.022994995,0.0072898865,0.018554688,-0.025985718,-0.007083893,-0.030288696,-0.03314209,-0.019195557,-0.0072021484,-0.023422241,0.023605347,-0.016540527,0.0020961761,0.001200676,-0.02217102,0.022140503,0.011604309,-0.0017518997,0.021072388,0.006084442,0.024002075,0.03665161,0.008621216,-0.052581787,0.024307251,-0.011444092,0.013954163,-0.012245178,0.045928955,0.03366089,-0.012542725,-0.0011587143,-0.007007599,-0.030685425,-0.020248413,0.0044784546,-0.004142761,0.011177063,-0.0034618378,-0.04473877,0.007041931,-0.004764557,-0.024597168,-0.03173828,0.010795593,0.009674072,-0.041900635,0.019927979,0.020248413,0.05368042,-0.02279663,0.01210022,0.007827759,0.052337646,0.045440674,0.006008148,-0.010421753,0.020095825,-0.011833191,0.012702942,-0.008483887,-0.0033473969,0.018707275,0.004699707,0.014503479,0.016311646,0.022247314,-0.024673462,-0.026000977,0.0118255615,-0.011390686,-0.027557373,0.027740479,0.025558472,0.022888184,-0.021469116,0.017318726,0.016952515,-0.01184845,-0.018737793,-0.01209259,0.039886475,-0.019470215,-0.010406494,0.022415161,0.00459671,0.023117065,-0.055389404,-0.0071144104,0.0112838745,0.009338379,-0.024368286,-0.056121826,-0.049743652,0.0056419373,0.027709961,0.0034618378,0.036010742,0.03463745,-0.007396698,0.005886078,0.025527954,-0.000107347965,-0.012916565,-0.011299133,-0.05404663,-0.030151367,-0.006374359,0.013282776,-0.03744507,0.019241333,-0.00843811,-0.031143188,0.00072050095,-0.016494751,-0.011299133,-0.021575928,0.012428284,0.026931763,0.008392334,0.022201538,-0.015235901,-0.030258179,-0.010406494,0.005329132,0.016708374,-0.046081543,0.021484375,-0.016448975,-0.013122559,-0.0052337646,0.017089844,0.025512695,0.027633667,0.019683838,0.031188965,-0.045562744,0.04336548,-0.030044556,0.026184082,-0.0035114288,-0.036621094,-0.021499634,-0.024368286,-0.011566162,0.045043945,-0.023345947,-0.010955811,-0.03665161,-0.032928467,-0.0055389404,-0.049621582,0.01763916,0.040527344,0.043884277,-0.020217896,0.0005874634,0.0014982224,0.009025574,-0.016571045,-0.0026397705,-0.013977051,0.022384644,0.022750854,0.006816864,-0.021057129,-0.025939941,-0.019012451,-0.0046157837,-0.057250977,-0.06008911,-0.012931824,0.007858276,-0.00995636,-0.014015198,-0.025299072,-0.04006958,0.0078048706,-0.037384033,0.018173218,0.0027866364,0.022659302,0.006793976,-0.022094727,0.0013046265,0.013557434,-0.018325806,0.033172607,0.006542206,-0.0016012192,-0.042816162,0.009399414,0.006214142,0.016586304,-0.0069007874,-0.021697998,-0.002855301,-0.024612427,-0.050201416,-0.010192871,0.0018758774,-0.016525269,-0.015090942,0.009147644,-0.059539795,0.0023059845,-0.020706177,-0.004085541,0.029159546,0.018295288,0.0077934265,-0.014595032,0.016021729,-0.011459351,-0.0046195984,-0.032104492,0.0124053955,0.0112838745,0.008918762,0.028656006,0.04815674,-0.010971069,-0.028244019,0.005191803,0.015411377,0.016586304,-0.020095825,0.008850098,-0.029449463,0.022613525,-0.0049476624,-0.014503479,-0.046325684,-0.006515503,0.08105469,0.0069274902,-0.024841309,-0.011550903,-0.019500732,0.012542725,0.038391113,-0.035583496,0.0025520325,-0.029052734,0.010681152,-0.026901245,0.011833191,0.0021762848,0.026779175,-0.01424408,-0.058807373,-0.007724762,0.0020046234,-0.0073776245,-0.0713501,-0.028656006,-0.067993164,-0.0013008118,-0.01058197,-0.035217285,0.00035119057,0.016983032,-0.01864624,-0.09124756,0.014556885,0.04425049,0.006790161,0.027664185,0.0024375916,0.024963379,0.038116455,-0.021865845,-0.006072998,0.028060913,-0.026931763,-0.028030396,-0.022949219,0.016113281,-0.0073432922,-0.011001587,0.008529663,0.013465881,0.012634277,0.00048446655,0.008056641,-0.014503479,0.029052734,-0.01234436,0.015625,-0.014770508,-0.010971069,0.037017822,-0.052215576,0.021026611,0.008110046,-0.005092621,0.009292603,0.03353882,0.04852295,-0.038360596,-0.010955811,0.008728027,0.006832123,0.0231781,-0.016159058,0.047332764,0.016464233,-0.016326904,0.006954193,-0.013748169,-0.021743774,-0.029663086,-0.029159546,0.025787354,0.004398346,0.010276794,-0.01928711,-0.0035247803,0.018356323,0.007637024,0.01309967,-0.0079193115,-0.017608643,-0.032989502,0.0072364807,0.005680084,0.007843018,-0.0019292831,0.026748657,0.024459839,0.038879395,0.006248474,-0.014793396,0.0056419373,0.029190063,-0.005306244,0.0011501312,0.02558899,0.0084991455,0.00705719,0.02180481,0.0066719055,-0.04901123,-0.007369995,-0.02394104,-0.022888184,0.0075302124,-0.0038719177,-0.012931824,-0.000098228455,-0.0002155304,-0.0138549805,-0.02368164,0.005393982,-0.024291992,-0.028915405,0.000040709972,-0.012001038,0.020645142,0.015274048,0.0007324219,0.008712769,-0.009880066,0.050933838,-0.000749588,-0.011054993,0.025482178,0.02999878,0.013938904,-0.037322998,-0.0115356445,-0.018081665,-0.0090408325,0.0015687943,-0.03881836,0.0143966675,0.032287598,-0.020065308,0.008201599,-0.0018863678,0.013389587,-0.007095337,-0.0034770966,-0.0085372925,0.017807007,-0.015304565,0.026382446,-0.058013916,0.019256592,0.006252289,0.008262634,-0.010848999,-0.021362305,-0.019500732,0.02041626,-0.0077056885,-0.008300781,0.04296875,0.0075912476,0.039520264,-0.020889282,-0.020370483,0.00021612644,-0.032440186,-0.026062012,0.014152527,-0.016052246,0.008201599,0.012062073,-0.032836914,0.020095825,-0.028945923,0.018005371,0.00019812584,-0.008514404,-0.013290405,-0.011779785,-0.0073623657,-0.0003490448,-0.027069092,-0.01008606,-0.008399963,0.04473877,0.016708374,0.032806396,0.036254883,0.016586304,0.005970001,-0.04168701,-0.028579712,0.0013160706,-0.016342163,0.02180481,-0.013397217,0.040740967,0.041748047,0.003250122,0.040893555,0.035064697,0.034179688,-0.0115356445,0.019012451,-0.02104187,0.018951416,-0.01473999,0.029006958,-0.001124382,0.04397583,-0.031066895,0.018692017,0.018615723,0.020812988,-0.017974854,0.036468506,0.06665039,0.017456055,0.00071430206,0.030334473,-0.003042221,-0.012863159,-0.0014877319,-0.028198242,0.048706055,0.021194458,0.053863525,0.045135498,0.0039787292,-0.0019721985,0.020584106,-0.031463623,-0.02267456,0.06359863,0.024887085,-0.020507812,-0.010719299,-0.0036754608,0.011634827,-0.03857422,-0.023254395,0.018295288,-0.0050354004,0.0007801056,-0.016296387,-0.0053634644,-0.011451721,0.0039405823,0.017532349,0.014190674,-0.017486572,0.0287323,0.025909424,0.013244629,0.027877808,-0.0048980713,0.028335571,-0.026229858,-0.018615723,0.017288208,0.027160645,-0.014312744,-0.0016584396,0.01928711,-0.0021953583,0.043426514,0.039794922,-0.018371582,0.004016876,0.029296875,0.01461792,0.0084991455,0.05090332,0.03213501,0.012969971,0.041870117,0.03427124,0.041290283,-0.03527832,0.022003174,-0.0036888123,-0.0012760162,-0.014007568,-0.012321472,0.006137848,-0.017303467,0.022354126,-0.012557983,-0.017562866,0.01676941,0.0178833,-0.006378174,-0.006576538,-0.009803772,0.015640259,-0.018585205,-0.0062408447,0.01651001,-0.010719299,0.031219482,0.017974854,0.025604248,-0.0259552,0.013961792,-0.008796692,-0.024658203,-0.0036849976,0.03186035,-0.039855957,0.01285553,-0.007633209,-0.003353119,-0.049072266,0.0062217712,0.023147583,-0.007255554,0.022949219,0.018417358,-0.0040359497,-0.008995056,0.032958984,0.01878357,0.0045051575,-0.009902954,-0.024963379,0.028457642,0.041656494,0.004135132,0.01008606,-0.005542755,-0.005367279,-0.00019812584,-0.0109939575,-0.004928589,-0.008766174,-0.013954163,-0.017044067,0.017486572,0.03390503,0.019638062,0.050323486,-0.0138549805,-0.014930725,0.007083893,0.035003662,0.0015964508,-0.0024738312,0.0057296753,0.02357483,-0.019821167,0.04168701,0.039123535,0.004501343,0.029449463,-0.003118515,-0.0038833618,0.015914917,-0.011306763,0.034362793,-0.01876831,-0.0034618378,-0.0028934479,0.025131226,-0.014167786,-0.041137695,0.010467529,-0.023880005,-0.022506714,-0.016082764,0.0059013367,-0.0013074875,0.021484375,0.038146973,0.019561768,-0.033996582,0.06341553,-0.012023926,0.045135498,-0.0019950867,-0.016967773,0.057617188,0.030639648,0.03564453,0.012107849,0.016403198,-0.043151855,0.022369385,0.030960083,0.025039673,0.0005245209,0.0024280548,-0.010696411,0.026824951,-0.007843018,0.034423828,-0.006996155,0.0024929047,0.011169434,-0.012207031,0.0014276505,-0.010002136,-0.005584717,-0.0027770996,0.0546875,-0.023132324,-0.0067481995,-0.03036499,-0.010917664,0.026123047,-0.006137848,0.0006108284,-0.012535095,-0.026382446,0.01499939,-0.016693115,-0.016494751,0.02293396,0.017501831,-0.05154419,-0.010864258,0.010406494,0.023986816,-0.02217102,0.027267456,0.025299072,-0.0015668869,0.010093689,0.0435791,-0.008552551,0.024749756,-0.011634827,0.02607727,0.031311035,0.0034713745,-0.01411438,-0.0014019012,0.00579834,-0.008956909,0.01940918,0.028656006,-0.018173218,-0.00217247,-0.0030269623,-0.0068626404,-0.009773254,0.007423401,-0.009361267,0.009185791,-0.0046577454,-0.004600525,0.0093688965,0.0115737915,0.000004172325,0.014823914,-0.00730896,-0.021270752,0.018936157,0.041168213,0.018234253,-0.030532837,-0.00856781,0.011489868,0.0026111603,-0.024002075,-0.02331543,-0.011550903,-0.037750244,0.011787415,0.01953125,0.010597229,0.015464783,-0.026565552,-0.000729084,0.01902771,0.00061035156,0.0116119385,0.009925842,-0.0084991455,0.009941101,-0.016937256,-0.008842468,-0.007217407,-0.016677856,0.018188477,0.027877808,-0.0024814606,-0.023223877,0.0259552,-0.010047913,0.0132369995,0.0012960434,-0.009460449,0.018615723,-0.009712219,-0.0017156601,-0.00092697144,0.018325806,-0.0022468567,0.004764557,-0.012138367,0.031036377,0.044921875,-0.013259888,-0.019973755,0.022323608,0.019119263,0.01625061,0.041778564,0.016052246,0.041046143,0.026107788,-0.013885498,-0.023010254,0.023101807,-0.0066108704,-0.02557373,0.0061950684,-0.0070228577,-0.004611969,0.0234375,0.011940002,-0.0037994385,-0.03012085,-0.016159058,-0.01763916,-0.017593384,0.019012451,0.00041413307,0.022232056,-0.023742676,-0.01436615,0.010169983,-0.026138306,-0.04067993,-0.016494751,0.00019586086,-0.01687622,-0.053863525,0.011634827,-0.018966675,0.012176514,-0.024230957,0.002105713,-0.006603241,0.021087646,-0.008865356,-0.005207062,-0.0018758774,0.016738892,0.030441284,0.00021898746,0.022583008,-0.024047852,-0.013389587,-0.021911621,0.019943237,-0.019073486,0.015625,0.008796692,0.03970337,0.015792847,-0.017547607,0.008369446,-0.008049011,-0.008285522,-0.015686035,-0.026519775,-0.02229309,0.026824951,0.02180481,0.0005941391,-0.011978149,0.031341553,-0.026443481,-0.0087890625,0.0256958,0.034454346,0.002986908,0.036376953,-0.018417358,0.0061569214,-0.017150879,-0.00036978722,-0.008117676,0.006511688,0.007583618,0.018661499,-0.005710602,0.006313324,0.02784729,-0.020019531,-0.0042381287,0.027420044,0.010574341,-0.004711151,0.043548584,0.026779175,0.012756348,-0.014259338,-0.004081726,0.016601562,0.05227661,0.007270813,0.013244629,0.0025520325,0.00459671,-0.013389587,0.010131836,0.008338928,-0.013618469,-0.04095459,-0.016220093,-0.03289795,0.028793335,-0.0021820068,-0.00039362907,-0.011062622,0.019012451,-0.011177063,-0.039855957,-0.022476196,0.034118652,0.020217896,-0.023635864,-0.009788513,0.005596161,0.02192688,-0.025634766,-0.003232956,-0.042175293,-0.03074646,-0.019104004,-0.01751709,0.029541016,0.014915466,-0.0071983337,-0.0015258789,0.00057315826,0.0008711815,-0.0027637482,0.01676941,-0.01424408,0.0030670166,0.020370483,0.019805908,-0.016464233,0.02178955,-0.008903503,-0.00073337555,0.00058841705,-0.016815186,0.009529114,-0.022476196,0.035614014,-0.0129776,-0.0037117004,0.028549194,0.00356102,0.013404846,-0.040374756,0.002784729,0.0023860931,-0.0048561096,0.049591064,-0.014060974,-0.021484375,0.007797241,-0.010787964,-0.02116394,-0.0027389526,0.012931824,0.0259552,0.0050354004,0.04421997,-0.0046195984,-0.0057754517,0.01348114,0.018493652,-0.014793396,0.0056037903,0.022567749,0.002796173,0.009094238,-0.0008792877,-0.007686615,-0.034057617,-0.009796143,0.018295288,-0.0031757355,-0.0155181885,0.018051147,0.016586304,0.048980713,0.0022220612,0.024749756,0.0131073,0.0017404556,0.04031372,0.0015735626,0.048980713,-0.0015497208,-0.031143188,-0.002735138,0.0022659302,-0.027816772,0.011360168,0.0035953522,0.0036621094,-0.035949707,0.012649536,0.0039749146,0.018157959,-0.008163452,0.01361084,-0.026168823,-0.015609741,-0.03137207,-0.0057373047,-0.037506104,0.0059394836,0.02684021,-0.0022125244,0.027954102,0.0009279251,-0.023391724,0.023345947,0.04220581,0.012321472,-0.023620605,-0.026931763,0.009727478,0.002090454,0.005558014,0.023345947,-0.018066406,-0.013420105,-0.001121521,-0.01737976,0.01525116,-0.012687683,0.016571045,0.0033226013,-0.0060577393,-0.010658264,0.021408081,-0.0056877136,-0.004924774,0.010894775,-0.0035152435,0.03152466,0.029022217,-0.013130188,0.010070801,0.01751709,-0.042663574,0.06237793,-0.013793945,0.028335571,-0.006996155,0.016464233,-0.04031372,-0.024841309,-0.013465881,0.011360168],"createdAt":"2026-04-18T18:59:25.857Z","updatedAt":"2026-04-22T11:32:21.335Z","lastSeenAt":"2026-04-22T11:32:21.335Z","tsv":"'/api':193 '/api/v1/transactions/250':117 '/docs':192 '/pricing':194 '/readme':196 '/request':19,38 '0.02':18,37,71,139,184 '000':133 '20':132 '402':127 '402 payment API' 'Base network API' 'USDC micropayment API' 'access':123 'actual':227 'advertis':144 'ai':12,31,155 'ai-classification' 'ai-embeddings' 'ai-sentiment' 'ai-summarization' 'ai/ml':57 'alon':241 'analysi':159 'analyt':56,149 'api':5,24,45,89,122 'attach':100 'avail':219 'base':8,27,79,134,141 'behavior':228 'broad':50 'call':4,23 'caller':98 'cannot':235 'categori':147 'challeng':128 'classif':162 'collect':51 'commit':97 'connect':202 'convers':178 'conversion' 'cover':10,29 'crawl':222 'data':11,30,55,61,148,152 'data-analytics' 'detail':209 'document':187,240 'embed':163 'enabl':44 'endpoint':16,35,53,67,114,146,234 'estim':173 'everi':66 'exampl':217 'exchang':168 'exchange-rates' 'export':153 'extrem':189 'feed':167 'financ':13,32,164 'finance/web3':59 'format':231 'four':145 'gas':172 'gas-estimates' 'general':63 'generat':179 'geocod':176 'geocoding' 'header':105 'i.e':138 'infer':58 'infrastructure/utilities':175 'insight':154 'key':90 'learn':157 'limit':93 'list':119 'low payment fee API' 'lowpaymentfee.com':39 'machin':156 'market':60 'metric':150 'micro-transaction API' 'minimum':96 'network':80 'offer':48 'openapi':211 'output':230 'page':197 'pay':2,21 'pay-per-cal':1,20 'pay-per-call API' 'pay-per-request' 'payment':84,104,110 'per':3,22,72 'platform':46 'point':186 'premium':121 'price':69,166,185 'price-feeds' 'probe':115 'prompt':204 'proof':111 'protocol':85 'public':239 'quot':171 'rate':92,169 'render':199 'report':151 'request':73,129 'request/response':213 'return':125 'schema':214 'sentiment':158 'servic':65 'settl':74 'share':181 'simpli':99 'site':143 'span':54 'spars':190 'spec':212 'specif':113 'suit':6,25 'summar':161 'technic':208 'text':160 'token':170 'unit':135 'usag':216 'usdc':9,28,76,137 'usdc-base' 'util':15,34,64 'valid':108,177 'validation' 'verifi':237 'via':81 'wallet':203 'web3':165 'x':103 'x-payment':102 'x402':43,83,109 'x402 API' 'x402-enabled':42 'x402-payment'","prices":[{"id":"23cc5248-8698-4c8b-b6e6-69812eb72ba9","listingId":"629a6086-4f56-4e9a-a563-9e0d1872dff3","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/transactions/250","description":"Premium API Access","outputSchema":{"input":{"type":"http","method":"GET","discoverable":true}},"maxAmountRequired":"20000","maxTimeoutSeconds":300}],"asset_contract":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","max_timeout_seconds":300},"createdAt":"2026-04-18T18:59:25.857Z"}],"sources":[{"listingId":"629a6086-4f56-4e9a-a563-9e0d1872dff3","source":"x402_bazaar","sourceId":"https://lowpaymentfee.com/api/v1/transactions/250","sourceUrl":"https://api.cdp.coinbase.com/platform/v2/x402/discovery/resources","isPrimary":true,"firstSeenAt":"2026-04-18T18:59:25.857Z","lastSeenAt":"2026-04-22T11:32:21.335Z"}],"details":{"listingId":"629a6086-4f56-4e9a-a563-9e0d1872dff3","quickStartSnippet":"curl -X POST https://lowpaymentfee.com/api/v1/transactions/250 \\\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 endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categories, all priced at $0.02/request","source_url":"https://lowpaymentfee.com"},{"claim":"Pricing is $0.02 per request with no API keys, no rate limits, and instant access on the Base network","source_url":"https://lowpaymentfee.com"},{"claim":"The x402 challenge for /api/v1/transactions/250 requests maxAmountRequired of 20000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Base","source_url":"https://lowpaymentfee.com/api/v1/transactions/250"}],"useCases":["Running sentiment analysis or text summarization without managing API keys or subscriptions","Fetching real-time crypto token quotes or gas estimates via micropayment","Geocoding addresses or validating data on a per-request payment basis","Exporting analytics data or generating insights with no rate limits","Generating embeddings for downstream ML pipelines"],"bestFor":["Developers wanting zero-signup, pay-as-you-go API access","AI agents that can settle x402 payments autonomously on Base","Projects needing low-cost, no-commitment access to diverse utility endpoints"],"notFor":["Users who need detailed API documentation or guaranteed SLAs before integrating","High-volume production workloads that benefit from bulk pricing or dedicated infrastructure","Teams without a Base-compatible USDC wallet"],"kindDetails":{"x402_version":1,"resource_type":"http","bazaar_last_updated":"2026-02-17T23:13:41.274Z"},"updatedAt":"2026-04-22T11:32:21.335Z"}}