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

# MCP Client Users

> Access paid MCP servers with just a few simple steps.

This guide is for MCP Client Users, to help you quickly connect to and use remote MCP Servers that use AgentPay for payments.

<Note>
  AgentPay is currently in **Early Access**. To get early access to AgentPay, please [sign up for the Waitlist here](https://agentpay.me).
</Note>

We'll cover:

1. Finding an MCP Server on **AgentPay Hub**.
2. Getting your **User API Key** for that Server.
3. Configuring your **MCP Client** (e.g. Claude, Cursor) to use the API Key.
4. Using free Server credit and topping up AgentPay balance.
5. Monitoring usage on AgentPay Hub.

Let's get you connected!

## 1. Find an MCP Server

First, you'll need to log in to the **AgentPay Hub** and find an MCP Server to start using.

**Steps:**

* **Sign Up / Log In:** Head over to [AgentPay Hub](https://agentpay.me) and sign up or log in.

<Note>
  As AgentPay is in **Early Access**, access is currently managed via our Waitlist, which you can [sign up for here](https://agentpay.me).
</Note>

* **Navigate to Discover:** Once logged in, you'll find a "Discover" tab in the main navigation.

```mermaid theme={null}
graph
    A(AgentPay Hub) --> B[Navigation Bar];
    B --> C[Dashboard];
    B --> D[Discover];
    B --> E[My API Keys];
    B --> F[My Servers];
    style D fill:#00E6E9,stroke:#333,stroke-width:2px,color:#333;
```

* **Browse or search** for MCP Servers by name or ID to see detailed metadata about each Server, including:
  * Pricing information
  * Availability of free credits
  * Server endpoint URL (needed for client configuration)
  * Description of available tools and features

## 2. Get Your User API Key

Ready to start using your chosen MCP Server? Here's how to get your access key:

1. Click the "Get API Key" button on the Server's card
2. Your unique **User API Key** will be displayed
3. **Important:** Copy and store your API Key securely - it will only be shown once!
4. The Server will now appear in your "My API Keys" tab with your API Key listed

What is a **User API Key**?

* Think of it as your personal access pass to the MCP Server
* It lets the server know who you are and manages your billing through AgentPay
* Each API Key is specific to one MCP Server, so you'll need a new one for each server you want to use

## 3. Configure Your MCP Client

To use the MCP Server, you'll need to configure your MCP Client application (e.g. Claude, Cursor, or others) to send your User API Key in the request headers. The standard header name is `X-AGENTPAY-API-KEY`.

### Example: `mcp.json`

If you are using an MCP Client like Claude or Cursor that uses an `mcp.json` configuration file, you would add the header there. Here's an example snippet for a remote MCP Server:

```json theme={null}
{
  "mcpServers": {
    "mcp-server-name": { // Choose a descriptive name
      "command": "npx",
      "args": [
        "-y",
        "mcp-remote",
        "<MCP_SERVER_URL>", // e.g., "http://mcpserver.io/sse"
        "--header",
        "X-AGENTPAY-API-KEY:YOUR_USER_API_KEY_HERE"
      ],
      "env": {}
    }
    // ... other server configurations
  }
}
```

* Replace `mcp-server-name` with a name you want to use for this tool in Cursor.
* Replace `<MCP_SERVER_URL>` with the MCP server's endpoint URL.
* Replace `YOUR_USER_API_KEY_HERE` with your actual User API Key.

Refer to your specific MCP client's documentation for the exact method of adding custom request headers.

Once configured, your client will send the API key with each request, allowing the MCP server (and AgentPay) to authenticate you and manage your usage.

## 4. Free Credits and Balance Topup

Let's talk about how your **balance** and **payments** work with AgentPay:

```mermaid theme={null}
    graph
        User[User] -- Account Balance --> AgentPay(AgentPay)
        AgentPay <-- Credits & Payments --> MCP1[MCP Server 1]
        AgentPay <-- Credits & Payments --> MCP2[MCP Server 2]
        AgentPay <-- Credits & Payments --> MCP3[MCP Server 3]
    
    style AgentPay fill:#00E6E9,stroke:#333,stroke-width:1px,color:#333;
```

When you first get an API Key for a Server:

* You'll receive \$1.00 in **free credit** to test out the Server.
* This free credit is specific to that Server only, and only available the **first time** you get an API Key for it.
* Once you use up the free credit, you'll start **making payments** from your AgentPay balance.

Your **AgentPay balance**:

* Works across **all MCP Servers** you use ⏤ one balance for everything!
* Can be **topped up anytime** using:
  * Credit cards (via Stripe)
  * Stablecoins
  * Other supported payment methods

## 5. Understanding Usage

Keep track of your **usage and spending** in the "My API Keys" tab on the **AgentPay Hub**:

```mermaid theme={null}
graph
    A(AgentPay Hub) --> B[Navigation Bar];
    B --> C[Dashboard];
    B --> D[Discover];
    B --> E[My API Keys];
    B --> F[My Servers];
    style E fill:#00E6E9,stroke:#333,stroke-width:2px,color:#333;
```

* View remaining free credit for each Server.
* See total spending and usage statistics.
* Review detailed usage history.

Here's how **billing** works with AgentPay:

* You'll be charged each time you make a paid call to an MCP Server.
* Pricing is transparently listed in the Server's metadata.
* If you notice any discrepancies:
  1. Contact the MCP Server developer directly.
  2. For serious issues, file a report with AgentPay.
     * We'll investigate and may refund usage or suspend problematic Servers.

That's it! You should now be able to use tools from the AgentPay-enabled MCP server. For more details on managing your API keys or account balance, please refer to the **MCP Client Users** section or visit the AgentPay Hub.