{
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  "type": "Article",
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  "title": "HTTP 402 & x402: How AI Agents Pay for Content",
  "description": "HTTP 402 Payment Required is a long-reserved HTTP status code that can signal a resource is behind payment, but it has no single standardized behavior across the web. The…",
  "canonical": "https://agentflare.org/research/http-402-x402-how-ai-agents-pay-for-content.html",
  "category": "research",
  "updated": "2026-06-15",
  "generated_at": "2026-06-15T01:19:16.018Z",
  "facts": [
    {
      "label": "Topic",
      "value": "agent-economy"
    },
    {
      "label": "Sources",
      "value": "10"
    },
    {
      "label": "Updated",
      "value": "2026-06-15"
    }
  ],
  "data": {
    "topic": "HTTP 402 and x402 protocol for AI agent payments",
    "cluster": "agent-economy",
    "summary": "HTTP 402 Payment Required is a long-reserved HTTP status code that can signal a resource is behind payment, but it has no single standardized behavior across the web. The…"
  },
  "analysis_md": "HTTP **402 Payment Required** is a long-reserved HTTP status code that can signal a resource is behind payment, but it has *no single standardized behavior* across the web. The newer **x402** protocol turns that dormant status code into a practical payment handshake for APIs and AI agents, especially for micropayments and pay-per-use access.[3][6]\n\n## HTTP 402: what it is and what it is not\n\nHTTP 402 is **reserved for future use** in the HTTP specification and remains **nonstandard** in practice.[3] MDN notes that no browser has native support for a special 402 flow, and implementations vary widely in how they use it.[3] In the wild, some services use 402 as a generic payment failure or subscription problem indicator, not as a true protocol for completing payment.[1][3]\n\nFor developers, that means a raw 402 response usually requires reading the provider’s documentation or response body to understand whether the issue is an expired subscription, failed card, quota overage, or a payment gate.[1][3]\n\n## What x402 adds\n\n**x402** is an application-layer payment protocol built around HTTP 402 to make payment requirements machine-readable and retryable.[5][6] In the x402 flow, a server returns a 402 response with payment details, such as amount, asset, destination, and acceptable payment options, so a client can pay programmatically and resend the request.[5][6]\n\nCoinbase’s x402 documentation describes this as a way to enable **API-native payments**, **micropayments**, and **machine-to-machine payments** without account creation or traditional billing flows.[6] The protocol is especially aimed at web services that want to expose paid endpoints directly over HTTP.[6]\n\n## Why AI agents care\n\nAI agents need to buy discrete actions: API calls, data, compute, and content access. Traditional billing assumes a human with an account, checkout flow, and sometimes CAPTCHA, which does not fit autonomous or high-frequency agent workflows.[7] x402 is designed to give agents a **wallet-native payment primitive** they can invoke inside a request-response cycle.[5][6]\n\nThat makes x402 relevant to **pay-per-crawl** and other retrieval use cases: a crawler or agent can discover that content is paid, receive the terms in 402, pay, and continue without manual intervention.[5][6]\n\n## Current practical view\n\nToday, HTTP 402 by itself is mostly an *informational signal* unless a service defines its own semantics.[1][3] x402 is the attempt to standardize a concrete payment flow on top of that status code, using crypto wallet rails and signed authorization to keep the interaction HTTP-native.[5][6]\n\n## Key takeaways\n\n- **HTTP 402** is reserved and still nonstandard; different services use it differently.[3]\n- **x402** turns 402 into a programmable payment handshake for HTTP APIs and agents.[5][6]\n- The main use case is **micropayments** and **pay-per-use access** without human-centered checkout flows.[6][7]\n- For AI agents, x402 is most useful when a task requires autonomous payment for API access, data, or crawl-time content.[5][6]",
  "sources": [
    {
      "url": "https://http.dev/402"
    },
    {
      "url": "https://www.youtube.com/watch?v=YzNi3jRf_7w"
    },
    {
      "url": "https://developer.mozilla.org/en-US/docs/Web/HTTP/Reference/Status/402"
    },
    {
      "url": "https://http.cat/status/402"
    },
    {
      "url": "https://bmdpat.com/blog/http-402-payment-required-x402"
    },
    {
      "url": "https://docs.cdp.coinbase.com/x402/core-concepts/http-402"
    },
    {
      "url": "https://ctse.aei.org/402-payment-required-the-http-code-that-waited-30-years-and-why-it-matters-today/"
    },
    {
      "title": "x402 Protocol Explained: How AI Agents Pay Onchain | Support",
      "url": "https://eco.com/support/en/articles/12328618-x402-protocol-explained-how-ai-agents-pay-onchain"
    },
    {
      "title": "x402 Payment Protocol: How AI Agents Will Pay Online",
      "url": "https://www.digitalapplied.com/blog/x402-payment-protocol-ai-agents-pay-coinbase-cloudflare"
    },
    {
      "title": "What is x402? | Payment Protocol for AI Agents on Solana",
      "url": "https://solana.com/x402/what-is-x402"
    }
  ],
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  "pricing": {
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    "method": "402",
    "endpoint": "https://cdn.aisa.one/api/v1/access/verify",
    "autopay_hint": "set crawlerAutoPrice=true with X-AISA-Crawler-Token",
    "onboarding": "https://cdn.aisa.one/cdn/guide.html"
  },
  "powered_by": "AISA — agent-native search, settlement & delivery (https://aisa.one)"
}