The x402 protocol repurposes the web's dormant "402 Payment Required" response into a native checkout: a service quotes its price, an app or agent signs a payment, and data or computing power is delivered once the transaction verifies. Coinbase created x402 in 2025 and contributed it to a Linux Foundation-backed body whose members include Visa, Mastercard, Stripe, Google and AWS. Cardano Foundation engineers worked from a specification accepted in June, building client, server and facilitator components that verify and submit payments in ADA or Cardano-issued tokens. The initial release supports TypeScript, with Python planned next.

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+2.8% 24h after post

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Thread · 1 event
  1. Leviathan published this article
  2. First reportCardano added to the official x402 software kit for AI-agent payments4 acc.

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Cited posts

  • @BSCNews BSCNFirst reportOn X ↗

    Cardano joins the legendary x402 stack. Designed by @coinbase, the x402 standard is purpose built for blockchain-based AI agent payments, and members include the likes of Visa, Mastercard, and Google. Now developers that leverage @Cardano's rails for just that purpose, with any…

  • @mpost_io Mpost Media GroupOn X ↗

    🤖 @Cardano has been added to the official x402 software kit, joining @solana and the @XRPLF in the race to power AI agent payments. The integration gives developers the code needed to let apps and #AI agents pay for online services using $ADA or #Cardano-issued tokens. x402…

  • @leviathan_news Leviathan NewsOn X ↗

    Cardano has been added to the official x402 software kit, giving developers the code needed to let an app or AI agent pay for an online service using ADA or tokens issued on the network. x402 turns the web's largely unused "402 Payment Required" response into a checkout built…

Show 1 more cited post
  • @wublockchain12 吴说区块链On X ↗

    据 CoinDesk，Cardano 已被纳入官方 x402 软件套件，开发者可构建使用 ADA 或 Cardano 生态代币自动支付在线服务的应用和 AI Agent。x402 最初由 Coinbase 于 2025 年推出，利用 HTTP 402 状态码实现原生互联网支付，目前 Solana、XRP Ledger 及多条 EVM 网络已支持该标准。https://t.co/PGG1Mmprzh

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Positioning · ADA

Open87 open positions · 83 long · 4 short

Tracked accounts lean long about 97% of the time, so a long-heavy book is normal, not a signal. As of 22 Sep 05:34 UTC.

Reaction since the first post

Since 22 Sep 02:08 UTC2 calls opened · 2 long · 0 short

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Crowding74th percentile · vs last 28 days, 50 typical
Pulse 24h94/100 · unusualness of new calls, 0–100, 50 typical, higher means more long than usual
Book97.3% long · 11,964 accounts

As of 22 Sep 05:00 UTC.

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