{"id":5613,"date":"2025-10-31T10:25:58","date_gmt":"2025-10-31T10:25:58","guid":{"rendered":"https:\/\/dev.adavault.com\/?p=5613"},"modified":"2025-10-31T10:27:58","modified_gmt":"2025-10-31T10:27:58","slug":"x402-25-years-later","status":"publish","type":"post","link":"https:\/\/dev.adavault.com\/index.php\/2025\/10\/31\/x402-25-years-later\/","title":{"rendered":"x402 25 years later&#8230;"},"content":{"rendered":"\n<p>You probably forgot about HTTP 402 Payment Required nestling between HTTP 401 Unauthorised, and 403 Access forbidden. We did.<\/p>\n\n\n\n<p>But now it&#8217;s getting resurrected for the crypto age and it may be the payment rails we&#8217;ve been waiting for.<\/p>\n\n\n\n<p>x402 is an open-source payment protocol developed by Coinbase in 2025, designed to enable instant, automated stablecoin payments directly over HTTP by activating the long-dormant HTTP 402 &#8220;Payment Required&#8221; status code. It serves as a chain-agnostic standard that allows AI agents, applications, and autonomous systems to send and receive money without human intervention, registrations, or complex integrations. So what are the key features?<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>HTTP-Native Integration<\/strong>: Builds on existing web infrastructure for seamless API monetization and resource access, supporting payments via simple HTTP requests.<\/li>\n\n\n\n<li><strong>AI and Agent Focus<\/strong>: Optimized for the &#8220;agentic economy,&#8221; enabling AI-driven transactions, on-chain settlements, and interoperability with ecosystems like Google\u2019s Agent Payments Protocol (AP2).<\/li>\n\n\n\n<li><strong>Ecosystem Applications<\/strong>: Powers tools for AI research platforms, DeFi execution, and agent commerce, with implementations on chains like Base, Avalanche, Solana, and BSC.<\/li>\n\n\n\n<li><strong>Security and Scalability<\/strong>: Includes verifiable computations and cryptographic proofs for secure, decentralised operations.<\/li>\n<\/ul>\n\n\n\n<p>x402 addresses a 25-year gap in internet payments by making them native to the web, fostering autonomous economies where agents can transact fluidly across Web2 and Web3. It&#8217;s gaining traction in AI and crypto communities, with Masumi taking the lead for Cardano.<\/p>\n\n\n\n<blockquote class=\"twitter-tweet\" data-theme=\"dark\"><p lang=\"zxx\" dir=\"ltr\"><a href=\"https:\/\/t.co\/dGSfo3spDC\">https:\/\/t.co\/dGSfo3spDC<\/a><\/p>&mdash; Masumi (@MasumiNetwork) <a href=\"https:\/\/twitter.com\/MasumiNetwork\/status\/1982898062847840519?ref_src=twsrc%5Etfw\">October 27, 2025<\/a><\/blockquote> <script async src=\"https:\/\/platform.twitter.com\/widgets.js\" charset=\"utf-8\"><\/script>\n\n\n\n<p>Check out their test implementation <a href=\"http:\/\/<blockquote class=&quot;twitter-tweet&quot; data-theme=&quot;dark&quot;&gt;<p lang=&quot;zxx&quot; dir=&quot;ltr&quot;&gt;<a href=&quot;https:\/\/t.co\/dGSfo3spDC&quot;&gt;https:\/\/t.co\/dGSfo3spDC<\/a&gt;<\/p&gt;&mdash; Masumi (@MasumiNetwork) <a href=&quot;https:\/\/twitter.com\/MasumiNetwork\/status\/1982898062847840519?ref_src=twsrc%5Etfw&quot;&gt;October 27, 2025<\/a&gt;<\/blockquote&gt; <script async src=&quot;https:\/\/platform.twitter.com\/widgets.js&quot; charset=&quot;utf-8&quot;&gt;<\/script&gt;\">here<\/a>.<\/p>\n\n\n\n<p>This one could be the first killer app for crypto beyond store of value.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>You probably forgot about HTTP 402 Payment Required nestling between HTTP 401 Unauthorised, and 403 Access forbidden. We did. But now it&#8217;s getting resurrected for the crypto age and it may be the payment rails we&#8217;ve been waiting for. x402 is an open-source payment protocol developed by Coinbase in 2025, designed to enable instant, automated&hellip;<\/p>\n","protected":false},"author":1,"featured_media":5615,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"inline_featured_image":false,"footnotes":""},"categories":[8],"tags":[181,501,500,499],"class_list":["post-5613","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-cardano-updates","tag-coinbase","tag-http-402","tag-masumi","tag-x402"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v26.6 - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>x402 25 years later... - ADAvault<\/title>\n<meta name=\"description\" content=\"The ADAvault blog\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/dev.adavault.com\/index.php\/2025\/10\/31\/x402-25-years-later\/\" \/>\n<meta property=\"og:locale\" content=\"en_GB\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"x402 25 years later... - 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