PayMCP – Monetize Your MCP Tools with Ease

PayMCP is a lightweight, provider‑agnostic SDK that turns any Model Context Protocol (MCP) tool or server into a fully‑functional payment gateway. By simply decorating a tool with , developers can expose that functionality to end users while automatically handling the entire checkout flow. The result is a frictionless, secure, and customizable payment experience that works across popular providers such as Stripe, Walleot, Coinbase, and any custom provider that implements the required interface.

Solving a Real‑World Problem

As AI assistants grow more capable, businesses need reliable ways to monetize niche or high‑value services—whether it’s a premium data query, an advanced analytical routine, or a custom business rule. Traditional payment integrations are often tied to specific frameworks and require significant boilerplate code, especially when dealing with asynchronous flows or multiple providers. PayMCP abstracts these complexities away: it plugs directly into the MCP tool/resource interface, supports multiple payment flows (two‑step, elicitation, progress), and guarantees that the tool’s logic is executed only after payment confirmation. This removes a major barrier to monetization for developers building AI agents and services.

Key Features & Capabilities

• Simple Decorator API – Add to any MCP tool and the SDK automatically handles payment logic.
• Multiple Payment Flows – Choose from , , or to match the user experience your client supports.
• Provider Flexibility – Plug in Stripe, Walleot, Coinbase, or any custom provider that implements . The first configured provider is used by default.
• FastMCP Integration – Works out‑of‑the‑box with FastMCP and other MCP servers, requiring no changes to existing server code.
• WebView Support – For stdio connections on desktop clients, PayMCP can open a lightweight webview to the payment URL, keeping users inside the application.

Real‑World Use Cases

• Premium AI Services – Charge for advanced language model queries, image generation, or data enrichment tools.
• Subscription‑Based Features – Implement recurring billing by extending the provider logic or combining with external subscription services.
• Marketplace Integration – Build a marketplace of AI tools where each tool can have its own price point and payment provider.
• Enterprise Licensing – Offer tiered access to corporate AI agents, with payments managed centrally via PayMCP.

Seamless Integration into AI Workflows

Because PayMCP operates at the MCP level, it is invisible to both the client and the AI model. The tool’s signature remains unchanged except for an optional parameter, and the payment flow is handled transparently. Developers can focus on building business logic while PayMCP ensures that the user is presented with a secure checkout, payment status is monitored, and the original tool logic only runs upon successful confirmation. This tight coupling with MCP makes PayMCP a natural fit for any AI assistant architecture that already uses tools and resources to extend capabilities.

Standout Advantages

• Zero Boilerplate – No need for custom routing, session handling, or webhook processing; PayMCP manages all payment lifecycle events.
• Open‑Source & Extensible – The provider interface is straightforward, encouraging community contributions and custom integrations.
• Cross‑Platform Compatibility – Works with any MCP client that supports the chosen flow, from web interfaces to CLI tools.
• Developer‑First Design – Clear documentation, minimal configuration, and the ability to test locally with stdio and webview support.

PayMCP empowers developers to monetize their AI tools quickly, securely, and with minimal friction—making it an essential component for any modern AI‑driven product.