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

# ATXP SDK Overview

> Complete overview of the ATXP SDK packages and their capabilities

# ATXP SDK Overview

The ATXP SDK is distributed as a modular collection of packages designed to integrate payment processing and authentication capabilities into Model Context Protocol (MCP) applications. The SDK is distributed as a modular collection of packages, allowing developers to use only the components they need for their specific use cases.

## Packages

The ATXP SDK is organized into several specialized packages, each serving a distinct purpose:

<CardGroup cols={2}>
  <Card title="@atxp/client" icon="laptop" href="/developers/api-reference/client">
    **Client-side integration** for MCP clients with OAuth authentication and payment processing capabilities.
  </Card>

  <Card title="@atxp/express" icon="server" href="/developers/api-reference/express">
    **Server-side middleware** for MCP servers with per-tool call payment processing and Express.js integration.
  </Card>

  <Card title="@atxp/base" icon="ethereum" href="/developers/api-reference/base">
    **Base integration** for using ATXP within Base Mini Apps and with Base accounts.
  </Card>

  <Card title="@atxp/common" icon="code" href="/developers/api-reference/common">
    **Shared utilities and types** providing common functionality across all ATXP SDK packages.
  </Card>
</CardGroup>