> ## Documentation Index
> Fetch the complete documentation index at: https://docs.x402r.org/llms.txt
> Use this file to discover all available pages before exploring further.

# What is x402r?

> x402r adds escrow deposits, refund windows, and dispute resolution to HTTP-native payments

**x402r** is a refundable payments protocol extension for [x402](https://www.x402.org/). It enables secure, reversible transactions with built-in buyer protection through smart contract escrow on Base.

## Why x402r

Standard x402 payments are immediate and irreversible. x402r adds:

* **Escrow deposits**: smart contracts hold funds until conditions clear
* **Refund windows**: configurable time periods for buyers to request refunds
* **Dispute resolution**: arbiter system for handling contested transactions

## How it works

```mermaid theme={null}
sequenceDiagram
    participant Client
    participant Merchant
    participant Escrow
    participant Arbiter

    Client->>Escrow: Pay (funds held)
    Escrow-->>Merchant: Payment notification

    alt Happy path
        Merchant->>Escrow: Capture funds
        Escrow->>Merchant: Transfer
    else Refund requested
        Client->>Escrow: Request refund
        Merchant->>Escrow: Approve/Deny
        alt Disputed
            Arbiter->>Escrow: Resolve dispute
        end
    end
```

## Who this is for

<CardGroup cols={3}>
  <Card title="Merchants (Receivers)" icon="store" href="/sdk/examples">
    Capture funds, process refunds, and manage escrow periods.
  </Card>
</CardGroup>

## Get started

<CardGroup cols={2}>
  <Card title="Protocol Overview" icon="diagram-project" href="/x402-integration/overview">
    Understand how x402r extends the x402 protocol.
  </Card>

  <Card title="Smart Contracts" icon="file-contract" href="/contracts/overview">
    Explore the escrow and payment operator contracts.
  </Card>

  <Card title="SDK Quickstart" icon="code" href="/sdk/overview">
    Start building with the TypeScript SDK.
  </Card>

  <Card title="Deploy an Operator" icon="rocket" href="/sdk/deploy-operator">
    Deploy your own PaymentOperator on Base.
  </Card>
</CardGroup>

## Architecture

x402r consists of these core components:

| Component                 | Purpose                                                                                     |
| ------------------------- | ------------------------------------------------------------------------------------------- |
| **PaymentOperator**       | Manages payment authorization, capture, charge, void, and refunds with pluggable conditions |
| **AuthCaptureEscrow**     | Holds ERC-20 tokens during the payment lifecycle (from commerce-payments)                   |
| **Conditions & Hooks**    | Pluggable authorization checks (before action) and state updates (after action)             |
| **EscrowPeriod & Freeze** | Time-based capture and freeze policies for buyer protection                                 |
| **RefundRequest**         | Handles refund request lifecycle and approvals                                              |

All protocol contracts use universal CREATE2 addresses, same address on every supported chain.

## Supported networks

Today, the supported chains in `@x402r/core` are **Base** and **Base Sepolia**. More EVMs land as canonical `base/commerce-payments@v1.0.0` coverage extends. See [Network support](/sdk/overview#network-support) for chain IDs and USDC token addresses.

## Resources

<CardGroup cols={3}>
  <Card title="GitHub" icon="github" href="https://github.com/BackTrackCo">
    Source code and examples.
  </Card>

  <Card title="SDK Reference" icon="book" href="/sdk/overview">
    SDK documentation and API reference.
  </Card>

  <Card title="Support" icon="envelope" href="mailto:hi@x402r.org">
    Get help with integration.
  </Card>
</CardGroup>