> ## 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.

# API Overview

> HTTPayer Proxy API documentation for payment-gated endpoints

# Overview

HTTPayer acts as a payment router for APIs using the 402 Payment Required status code and x402 Protocol. The proxy handles:

* Payment verification and processing
* Cross-chain USDC settlements
* Request forwarding to destination endpoints
* Response delivery to clients

## Authentication

Only account-based endpoints (`/proxy`, `proxy/sim`, `/balance`) require an API key; `/relay` is an x402-enabled endpoint.

## CORS

Cross-origin requests are **disabled by default**. The server only allows cross-origin requests from origins listed in the `CORS_ORIGIN` environment variable (comma-separated). If you are integrating from a browser, contact the HTTPayer team to have your origin allowlisted.

## Base URL

* `https://api.httpayer.com`

## Getting Started

The API endpoints are organized into the following groups:

* **Payment Relay**: Core payment processing and relay endpoints
* **Simulation**: Test payment flows without executing transactions
* **Account Management**: Check balances and limits
* **Webhooks**: Async refund tracking
* **LLM Endpoints**: AI-powered translation and chat features
* **System**: Health checks and configuration

Browse the endpoint documentation in the sidebar to get started.