References

x402 core docs

• Welcome to x402 (overview & goals). (Coinbase Developer Docs)

• How x402 Works (end-to-end HTTP-402 flow). (Coinbase Developer Docs)

• Facilitator (verification & settlement model). (Coinbase Developer Docs)

• Network & Token Support (includes SPL tokens on Solana). (Coinbase Developer Docs)

• Quickstart for Buyers (client behavior & retry semantics). (Coinbase Developer Docs)

• x402 GitBook (community guide). (GitBook)

• Coinbase Developer Platform: x402 product page. (Coinbase)

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Protocol background

• HTTP 402 Payment Required — MDN Web Docs. (MDN Web Docs)

• HTTP status reference index — MDN Web Docs. (MDN Web Docs)

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Solana-specific resources

• What is x402? (Solana’s x402 explainer). (Solana)

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Tools & open source

• x402 reference implementation (GitHub). (GitHub)

• x402-solana package (npm). (npm)

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Ecosystem & updates

• Cloudflare: Launching the x402 Foundation (ecosystem governance). (The Cloudflare Blog)