Documentation Index

Fetch the complete documentation index at: https://docs.httpayer.com/llms.txt

Use this file to discover all available pages before exploring further.

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Changelog

All notable changes to the HTTPayer API will be documented on this page.

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[1.1.0] - 2026-02-27

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Changed

• Proxy 502 on upstream payment refusal — When the target API returns 402 after all sync retries, the proxy now returns 502 Bad Gateway instead of silently dropping the response. The response body includes an optional webhook_id when background blockchain polling is active — use GET /webhooks/:id to track whether the payment eventually confirms on-chain.
• No more 202 responses — Async status is tracked via the webhook_id field on 502 proxy responses. Webhook records still transition through async_processing → terminal state as before.

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[1.0.0] - 2026-01-06

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Added

• Core Endpoints: Initial release with payment-gated API functionality
  • POST /sim - Simulate payment requests without execution
  • POST /proxy - Execute x402 payment-gated API calls with credits
  • POST /relay - Make privacy-preserving, cross-chain enabled API calls through a x402 client
  • GET /balance - Check account credits balance
• Payment Features:
  • EIP-3009 gasless USDC transfers using transferWithAuthorization
  • Multi-chain support: Base, Base Sepolia, SKALE Base, SKALE Base Sepolia, Solana, Solana Devnet
  • Payment verification and retry logic
  • Async refunds via webhooks
• Relay Features:
  • POST /relay/sim - Simulate relay payments
  • GET /relay/limits/{address} - Check wallet spending limits
  • Custom header forwarding to target APIs
• Webhook System:
  • GET /webhooks/{id} - Get async task status
• LLM Integration:
  • GET /llm/health - LLM service health check
  • POST /llm/translate - Translate text to Spanish
  • POST /llm/chat - General-purpose chat endpoint
• System Endpoints:
  • GET /health - Service health check
  • GET /config - Server configuration

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Security

• API key authentication via x-api-key header for account-based endpoints
• Payment signature validation using EIP-3009
• Rate limiting per wallet address

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Migration Guides

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Version History

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Subscribe to Updates

Stay informed about API changes:

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Changelog Format

We follow Keep a Changelog conventions:

• Added: New features and endpoints
• Changed: Changes in existing functionality
• Deprecated: Soon-to-be removed features
• Removed: Removed features
• Fixed: Bug fixes
• Security: Security vulnerability fixes

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Last Updated: 2026-02-27